JP2012054231A - Nonaqueous electrolyte and nonaqueous electrolyte battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a nonaqueous electrolyte battery in which durability characteristics upon cycles, preservation or the like and/or load characteristics are improved, and to provide nonaqueous electrolyte suitable for the nonaqueous electrolyte battery.SOLUTION: The nonaqueous electrolyte contains: lithium salt; and nonaqueous solvent dissolving this. The nonaqueous electrolyte contains: carbonate having a fluorine atom; and a compound represented by the following general formula (1).

Description

  The present invention relates to a non-aqueous electrolyte and a non-aqueous electrolyte secondary battery, and more specifically, a non-aqueous electrolyte containing a specific cyclic compound having a triple bond as an electrolyte, and a non-aqueous electrolysis using the non-aqueous electrolyte. It relates to a liquid battery.

  Non-aqueous electrolyte secondary batteries such as lithium secondary batteries are widely used as power sources for so-called portable electronic devices such as mobile phones and notebook computers, to in-vehicle power sources for automobiles and large power sources for stationary applications. It is being put into practical use. However, with the recent high performance of electronic devices and the application to in-vehicle power supplies for driving and large power supplies for stationary applications, the demand for applied secondary batteries is increasing, and the high performance of the battery characteristics of secondary batteries is increasing. For example, it is required to achieve high levels of improvement in capacity, high temperature storage characteristics, cycle characteristics, and the like.

  The electrolyte used for the non-aqueous electrolyte lithium secondary battery is usually composed mainly of an electrolyte and a non-aqueous solvent. The main components of the non-aqueous solvent include cyclic carbonates such as ethylene carbonate and propylene carbonate; chain carbonates such as dimethyl carbonate, diethyl carbonate and ethyl methyl carbonate; cyclic carboxylic acid esters such as γ-butyrolactone and γ-valerolactone. It is used. In addition, various nonaqueous solvents, electrolytes, auxiliaries, and the like have been proposed in order to improve battery characteristics such as load characteristics, cycle characteristics, storage characteristics, and low temperature characteristics of batteries using these nonaqueous electrolyte solutions. . For example, in a non-aqueous electrolyte using a carbon material for the negative electrode, by using vinylene carbonate and its dielectric or vinyl ethylene carbonate derivative, these cyclic carbonates react preferentially with the negative electrode, and a good quality coating is formed on the negative electrode surface. Patent Documents 1 and 2 disclose that the storage characteristics and cycle characteristics of the battery are improved. In addition, for example, in a non-aqueous electrolyte using artificial graphite as a negative electrode active material, by combining a specific ethylene carbonate derivative with a triple bond-containing compound and / or a pentafluorophenyloxy compound, gas generation is reduced and cycle characteristics are reduced. It is disclosed in Patent Document 3 that the above is improved.

JP-A-8-45545 JP-A-4-87156 WO 2006-077763

  As described above, the demand for higher performance of the secondary battery in recent years is increasing, and thus the improvement of the characteristics of the lithium secondary battery, that is, the improvement of the capacity, the high temperature storage characteristic, the cycle characteristic and the like is required. In such a background, in the nonaqueous electrolyte battery using the electrolyte solution described in Patent Documents 1 and 2, if the charged battery is left at a high temperature or a continuous charge / discharge cycle is performed, However, there is a problem that the unsaturated cyclic carbonate or a derivative thereof oxidizes and decomposes to generate carbon dioxide gas. If carbon dioxide gas is generated in such a use environment, the battery itself may become unusable due to, for example, activation of a battery safety valve or expansion of the battery.

In addition, the oxidative decomposition of unsaturated cyclic carbonate on the positive electrode causes a problem of generating a solid decomposition product in addition to the generation of carbon dioxide gas. Generation of such a solid decomposition product causes clogging of the electrode layer and the separator to inhibit the movement of lithium ions, or the solid decomposition product remains on the surface of the electrode active material and causes the lithium ion insertion / release reaction. May interfere. As a result, for example, the charge / discharge capacity may gradually decrease during a continuous charge / discharge cycle, the charge / discharge capacity may decrease from the initial stage after storage at a high temperature of the battery or after a continuous charge / discharge cycle, or the load characteristics may deteriorate. .

  Also, the oxidative decomposition of unsaturated cyclic carbonate on these positive electrodes becomes a particularly serious problem under the design of high performance secondary batteries in recent years. That is, this oxidative decomposition tends to become prominent when the potential at which the positive electrode active material inserts and desorbs lithium rises above the redox potential of lithium. For example, when an attempt is made to operate at a voltage higher than 4.2 V, which is a battery voltage at the time of full charge of a currently available lithium secondary battery, these oxidation reactions are particularly prominent.

  As a method for preventing the oxidative decomposition of the unsaturated cyclic carbonate on the positive electrode, studies using a saturated cyclic carbonate having a fluorine atom such as monofluoroethylene carbonate have been made. Usually, a saturated cyclic carbonate having a fluorine atom has higher oxidation resistance than an unsaturated cyclic carbonate. However, the negative electrode film formed by the saturated cyclic carbonate having fluorine atoms has poor durability, and as a result, there is a problem that carbon dioxide gas is generated.

Also, the non-aqueous electrolyte battery as an alternative to high capacity, limited but it has been studied to pack as much of the active material in the battery volume, the active material layer pressurizes Thus electrode In a battery designed to increase the density or reduce the volume other than the active material in the battery as much as possible, there are few voids inside the battery, and even if a small amount of gas is generated, the internal pressure of the battery rises significantly, and the safety valve The battery itself may become unusable due to operation or expansion of the battery.

  Patent Document 3 describes a non-aqueous electrolyte secondary battery using artificial graphite as a negative electrode active material and a triple bond-containing compound or the like as a non-aqueous electrolyte. Here, a triple bond-containing compound or the like is used as a non-aqueous electrolyte in order to improve cycle characteristics, but there is a problem that the side characteristics of the electrolytic solution are high and the cycle characteristics are difficult to improve.

  Therefore, the present invention solves the above-mentioned various problems that are manifested in the required performance of secondary batteries in recent years, and in particular, a non-aqueous electrolyte battery having improved durability characteristics such as cycle and storage and load characteristics. It is to provide a non-aqueous electrolyte suitable for the non-aqueous electrolyte battery.

  As a result of intensive studies to solve the above-mentioned problems, the inventors have expressed a carbonate having fluorine atoms in the non-aqueous electrolyte solution used in the non-aqueous electrolyte battery and the following general formula (1). It has been found that a non-aqueous electrolyte battery with improved durability characteristics such as cycle and storage and load characteristics can be realized by containing the compound, and the present invention has been completed. That is, the gist of the present invention is as follows.

  a) A non-aqueous electrolyte solution comprising a lithium salt and a non-aqueous solvent for dissolving the lithium salt, wherein the non-aqueous electrolyte solution is a carbonate having a fluorine atom and a compound represented by the following general formula (1) The present invention relates to a non-aqueous electrolyte solution containing

(In the above general formula (1), X and Z represent CR ¹ ₂ , C═O, C═N—R ¹ , C = P—R ¹ , O, S, N—R ¹ , P—R ¹ . Y may represent CR ¹ ₂ , C═O, S═O, S (═O) ₂ , P (═O) —R ² , P (═O) —OR ³ . In the general formula (1), R and R ¹ are hydrogen, halogen, or an optionally substituted hydrocarbon group having 1 to 20 carbon atoms, which may be the same or different from each other. R ² is an optionally substituted hydrocarbon group having 1 to 20 carbon atoms R ³ is Li, NR ⁴ ₄ or an optionally substituted carbon atom having 1 to 20 carbon atoms R ⁴ is a hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and may be the same or different, and n and m represent an integer of 0 or more. In the adjacent ring The elements may form a further bond with each other, and the R of the carbon may be reduced by one each, W is in the same range as R, and W may be the same as or different from R. )

  b) The non-aqueous electrolyte solution according to a), wherein the compound represented by the general formula (1) is a compound represented by the following general formula (2).

(In the general formula (2), Y represents C═O, S═O, S (═O) ₂ , P (═O) —R ² , P (═O) —OR ^3. R ² represents substitution. R ³ is a hydrocarbon group having 1 to 20 carbon atoms which may have a group, and R ³ is Li, NR ⁴ ₄ or a hydrocarbon group having 1 to 20 carbon atoms which may have a substituent. R ⁴ is an optionally substituted hydrocarbon group having 1 to 20 carbon atoms, which may be the same or different.

c) The non-aqueous electrolyte according to a) or b), wherein the carbonate having a fluorine atom is a cyclic carbonate.

d) The carbonate having a fluorine atom is fluoroethylene carbonate, 4,5-difluoroethylene carbonate, bis (2,2,2-trifluoroethyl) carbonate, or 2,2,2-trifluoroethylmethyl carbonate. , A) to c) The nonaqueous electrolytic solution according to any one of the above.

e) The non-aqueous electrolyte solution according to any one of a) to d), wherein the carbonate having a fluorine atom is contained in an amount of less than 50% by mass in the non-aqueous electrolyte solution.

f) When the content of the carbonate having a fluorine atom in the non-aqueous electrolyte is [A] and the content of the compound represented by the general formula (1) is [B], [B] / [A ] Is 5 to 0.0001, The non-aqueous electrolyte solution according to any one of a) to e).

g) A non-aqueous electrolyte battery comprising a negative electrode and a positive electrode capable of occluding and releasing lithium ions, and a non-aqueous electrolyte solution, wherein the non-aqueous electrolyte solution is a non-aqueous electrolyte according to any one of a) to f) above. The present invention relates to a non-aqueous electrolyte battery characterized by being a liquid.

h) The non-aqueous electrolyte battery according to g), wherein the negative electrode is a carbonaceous material.

  One feature of the present invention is that a compound in which a triple bond is bonded to a ring structure by a single bond without using any other functional group or heteroelement is used in a non-aqueous electrolyte battery. Usually, as typified by Patent Documents 1 and 2, many of the materials that protect the electrode surface and improve battery durability such as storage characteristics and cycle characteristics are compounds of a cyclic structure, and further have multiple bonding sites. Have. The present inventors paid attention to this point, and examined in detail the bonding sites of functional groups and heteroelements in the ring structure, the sites where multiple bonds are bonded to the ring structure, and the hybrid state of the electron orbits of the multiple bonds. As a result, for example, a compound in which a double bond is bonded to a ring structure is more stable with a positive electrode than a compound in which a part of the ring skeleton constituting the cyclic compound is a double bond, In addition, when the triple bond substituent is bonded to the ring structure, an effect (Example 16 and Comparative Example 9) having superior durability characteristics than the double bond can be obtained, and the above problems can be solved. Obtained knowledge.

  Moreover, the cyclic compound having a triple bond is reduced and decomposed at a higher potential than the saturated cyclic carbonate having a fluorine atom to form a good quality negative electrode film, and the reductive decomposition of the saturated cyclic carbonate having a fluorine atom can be suppressed. In addition, both the saturated cyclic carbonate having a fluorine atom and the cyclic compound having a triple bond are excellent in stability with the positive electrode. The inventors contain the triple bond cyclic compound and a saturated cyclic carbonate having a fluorine atom, and when the total content of the compound having a fluorine atom relative to the whole non-aqueous solvent is less than 50% by mass, The inventors have also found that the effects of the present invention are particularly prominent, and have completed the present invention.

  That is, by using the present invention as described above, the non-aqueous electrolyte solution has improved battery load characteristics, durability characteristics such as cycle and storage, especially in the design of lithium secondary batteries with higher voltages and higher capacities. A battery and a non-aqueous electrolyte used for the non-aqueous electrolyte are provided.

  Hereinafter, embodiments of the present invention will be described in detail, but the present invention is not limited to these embodiments, and can be arbitrarily modified and implemented.

1. Non-aqueous electrolyte 1-1. Electrolyte <Lithium salt>
As the electrolyte, a lithium salt is usually used. The lithium salt is not particularly limited as long as it is known to be used for this purpose, and any lithium salt can be used. Specific examples include the following.

For _{example, LiPF 6, LiBF 4, LiClO} 4, LiAlF 4, LiSbF 6, inorganic lithium salts LiTaF _6, LiWF ₇ and the like;
Lithium fluorophosphates such as LiPO ₃ F and LiPO ₂ F ₂ ;
Lithium tungstates such as LiWOF ₅ ;
HCO ₂ Li, CH ₃ CO ₂ Li, CH ₂ FCO ₂ Li, CHF ₂ CO ₂ Li, CF ₃ CO ₂ Li, CF ₃ CH ₂ CO ₂ Li, CF ₃ CF ₂ CO ₂ Li, CF ₃ CF ₂ CF ₂ Carboxylic acid lithium salts such as CO ₂ Li, CF ₃ CF ₂ CF ₂ CF ₂ CO ₂ Li;
FSO ₃ Li, CH ₃ SO ₃ Li, CH ₂ FSO ₃ Li, CHF ₂ SO ₃ Li, CF ₃ SO ₃ Li, CF ₃ CF ₂ SO ₃ Li, CF ₃ CF ₂ CF ₂ SO ₃ Li, CF ₃ CF ₂ Sulfonic acid lithium salts such as CF ₂ CF ₂ SO ₃ Li;
LiN (FCO) ₂ , LiN (FCO) (FSO ₂ ), LiN (FSO ₂ ) ₂ , LiN (FSO ₂ ) (CF ₃ SO ₂ ), LiN (CF ₃ SO ₂ ) ₂ , LiN (C ₂ F ₅ SO ₂ ) ₂ , lithium imide salts such as lithium cyclic 1,2-perfluoroethanedisulfonylimide, lithium cyclic 1,3-perfluoropropane disulfonylimide, LiN (CF ₃ SO ₂ ) (C ₄ F ₉ SO ₂ ) ;
Lithium metide salts such as LiC (FSO ₂ ) ₃ , LiC (CF ₃ SO ₂ ) ₃ , LiC (C ₂ F ₅ SO ₂ ) ₃ ;
Lithium difluorooxalatoborate, lithium bis (oxalato) borate, lithium bis (malonato) borate, lithium difluoro (malonato) borate, lithium bis (methylmalonate) borate, lithium difluoro (methylmalonato) borate, lithium bis (dimethylmalonato) borate, Lithium oxalatoborate salts such as lithium difluoro (dimethylmalonato) borate;
Lithium tetrafluorooxalatophosphate, lithium difluorobis (oxalato) phosphate, lithium tris (oxalato) phosphate, lithium tris (malonato) phosphate, lithium difluorobis (malonato) phosphate, lithium tetrafluoro (malonato) phosphate, lithium tris (Methylmalonate) phosphate, Lithium difluorobis (methylmalonate) phosphate, Lithium tetrafluoro (methylmalonate) phosphate, Lithium tris (dimethylmalonate) phosphate, Lithium difluorobis (dimethylmalonate) phosphate, Lithium tetrafluoro (dimethylmalonate) phosphate, etc. Lithium oxalatophosphate salts of
In addition, LiPF ₄ (CF ₃ ) ₂ , LiPF ₄ (C ₂ F ₅ ) ₂ , LiPF ₄ (CF ₃ SO ₂ ) ₂ , LiPF ₄ (C ₂ F ₅ SO ₂ ) ₂ , LiBF ₃ CF ₃ , LiBF ₃ C ₂ F ₅ , LiBF ₃ C ₃ F ₇ , LiBF ₂ (CF ₃ ) ₂ , LiBF ₂ (C ₂ F ₅ ) ₂ , LiBF ₂ (CF ₃ SO ₂ ) ₂ , LiBF ₂ (C ₂ F ₅ SO ₂ ) ₂ Fluorine-containing organic lithium salts such as
Etc.

Among them, LiPF ₆ , LiBF ₄ , LiSbF ₆ , LiTaF ₆ , LiPO ₂ F ₂ , FSO ₃ Li, CF ₃ SO ₃ Li, LiN (FSO ₂ ) ₂ , LiN (FSO ₂ ) (CF ₃ SO ₂ ), LiN ( CF ₃ SO ₂ ) ₂ , LiN (C ₂ F ₅ SO ₂ ) ₂ , lithium cyclic 1,2-perfluoroethanedisulfonylimide, lithium cyclic 1,3-perfluoropropane disulfonylimide, LiC (FSO ₂ ) ₃ , LiC (CF ₃ SO ₂ ) ₃ , LiC (C ₂ F ₅ SO ₂ ) ₃ , lithium bisoxalatoborate, lithium difluorooxalatoborate, lithium tetrafluorooxalatophosphate, lithium difluorobisoxalatophosphate, LiBF _{3 CF 3, LiBF 3 C 2 F} 5, LiPF 3 (CF 3) 3, LiPF 3 (C 2 F 5) 3 , etc. Output characteristics and high-rate discharge characteristics, high-temperature storage characteristics, particularly preferred from the viewpoint that an effect of improving the cycle characteristics and the like.

The concentration of these lithium salts in the non-aqueous electrolyte solution is not particularly limited as long as the effects of the present invention are not impaired, but the electric conductivity of the electrolyte solution is in a good range, and good battery performance is ensured. Therefore, the total molar concentration of lithium in the non-aqueous electrolyte is preferably 0.3 mol / L or more, more preferably 0.4 mol / L or more, and further preferably 0.5 mol / L or more. Preferably it is 3 mol / L or less, More preferably, it is 2.5 mol / L or less, More preferably, it is 2.0 mol / L or less. If it is this range, effects, such as a low temperature characteristic, cycling characteristics, and a high temperature characteristic, will improve. On the other hand, if the total molar concentration of lithium is too low, the electrical conductivity of the electrolyte may be insufficient. On the other hand, if the concentration is too high, the electrical conductivity may decrease due to an increase in viscosity. May decrease.

Moreover, these lithium salts may be used independently or may use 2 or more types together. A preferable example in the case of using two or more kinds in combination is a combination of LiPF ₆ and LiBF ₄ , LiPF ₆ and FSO ₃ Li, LiPF ₆ and LiPO ₂ F _2, etc., and has an effect of improving load characteristics and cycle characteristics. . Among these, the combined use of LiPF ₆ and FSO ₃ Li and LiPF ₆ and LiPO ₂ F ₂ is preferable because the effect is remarkable, and among them, the combined use of LiPF ₆ and LiPO ₂ F ₂ is a remarkable effect with a small amount of addition. Is particularly preferred because

When LiPF ₆ and LiBF ₄ , LiPF ₆ and FSO ₃ Li are used in combination, the concentration of LiBF ₄ or FSO ₃ Li with respect to 100% by mass of the entire non-aqueous electrolyte is not limited, and the effects of the present invention are not significantly impaired. As long as it is optional, it is usually 0.01% by mass or more, preferably 0.1% by mass or more, and the upper limit is usually 30% by mass or less, preferably 20% with respect to the non-aqueous electrolyte solution of the present invention. It is below mass%. On the other hand, even when LiPF ₆ and LiPO ₂ F ₂ are used in combination, the concentration of LiPO ₂ F ₂ with respect to 100% by mass of the total amount of the non-aqueous electrolyte is not limited as long as the effect of the present invention is not significantly impaired. However, with respect to the non-aqueous electrolyte solution of the present invention, it is usually 0.001% by mass or more, preferably 0.01% by mass or more, while its upper limit is usually 10% by mass or less, preferably 5% by mass or less. is there. Within this range, effects such as output characteristics, load characteristics, low temperature characteristics, cycle characteristics, and high temperature characteristics are improved. On the other hand, if it is too much, it may be deposited at low temperature to deteriorate the battery characteristics, and if it is too little, the effect of improving the low temperature characteristics, cycle characteristics, high temperature storage characteristics, etc. may be reduced. Another example is the combined use of an inorganic lithium salt and an organic lithium salt, and the combined use of both has the effect of suppressing deterioration due to high-temperature storage. Examples of the organic lithium salt include CF ₃ SO ₃ Li, LiN (FSO ₂ ) ₂ , LiN (FSO ₂ ) (CF ₃ SO ₂ ), LiN (CF ₃ SO ₂ ) ₂ , LiN (C ₂ F ₅ SO ₂ ) _2. , Lithium cyclic 1,2-perfluoroethanedisulfonylimide, lithium cyclic 1,3-perfluoropropane disulfonylimide, LiC (FSO ₂ ) ₃ , LiC (CF ₃ SO ₂ ) ₃ , LiC (C ₂ F ₅ SO _{2) 3} lithium Bisuo Kisara oxalatoborate, lithium difluoro oxalatoborate, lithium tetrafluoro-oxa Lato phosphate, lithium difluoro bis oxa Lato _{phosphate, LiBF 3 CF 3, LiBF 3} C 2 F 5, LiPF 3 (CF 3) 3 LiPF ₃ (C ₂ F ₅ ) ₃ or the like is preferable. In this case, the ratio of the organic lithium salt to 100% by mass of the whole non-aqueous electrolyte is preferably 0.1% by mass or more, particularly preferably 0.5% by mass or more, preferably 30% by mass or less, particularly preferably. It is 20 mass% or less.

Here, the preparation of the electrolyte solution in the case of incorporating the LiPO ₂ F ₂ in the electrolyte solution, Ya separately active material method and later be added to the electrolytic solution containing LiPF ₆ and LiPO ₂ F ₂ synthesized by a known method A method of generating LiPO ₂ F ₂ in the system when water is allowed to coexist in a battery component such as an electrode plate and assembling a battery using an electrolyte containing LiPF ₆ is used. You may use the method of.

The method for measuring the content of LiPO ₂ F ₂ in the non-aqueous electrolyte and the non-aqueous electrolyte battery is not particularly limited, and any known method can be used. Examples include ion chromatography and F nuclear magnetic resonance spectroscopy (hereinafter sometimes abbreviated as NMR).

1-2. Solvent In the non-aqueous electrolyte battery of the present invention, other non-aqueous solvents may be used depending on the purpose in addition to the carbonate having a fluorine atom and the compound represented by the general formula (1). As the non-aqueous solvent, it is possible to use saturated cyclic carbonates, saturated chain carbonates, cyclic and chain carboxylic acid esters, ether compounds, sulfone compounds, and the like.

<Saturated cyclic carbonate>
Examples of the saturated cyclic carbonate include those having an alkylene group having 2 to 4 carbon atoms.
Specifically, examples of the saturated cyclic carbonate having 2 to 4 carbon atoms include ethylene carbonate, propylene carbonate, and butylene carbonate. Among these, ethylene carbonate and propylene carbonate are particularly preferable from the viewpoint of improving battery characteristics resulting from an improvement in the degree of lithium ion dissociation.

  A saturated cyclic carbonate may be used individually by 1 type, and may have 2 or more types together by arbitrary combinations and ratios.

  The blending amount of the saturated cyclic carbonate is not particularly limited and is arbitrary as long as the effects of the present invention are not significantly impaired. However, the lower limit of the blending amount when one kind is used alone is 3 in 100% by mass of the non-aqueous solvent. It is at least 5% by mass, more preferably at least 5% by mass. By setting this range, the decrease in electrical conductivity resulting from the decrease in the dielectric constant of the non-aqueous electrolyte is avoided, and the large current discharge characteristics, negative electrode stability, and cycle characteristics of the non-aqueous electrolyte secondary battery are good. It becomes easy to be in a range. Moreover, an upper limit is 90 weight% or less, More preferably, it is 85 weight% or less, More preferably, it is 80 weight% or less. By setting it as this range, the viscosity of the non-aqueous electrolyte solution is set to an appropriate range, a decrease in ionic conductivity is suppressed, and as a result, the load characteristics of the non-aqueous electrolyte secondary battery are easily set in a favorable range.

  Moreover, a saturated cyclic carbonate can also be used in arbitrary combinations of 2 or more types. One preferred combination is a combination of ethylene carbonate and propylene carbonate. In this case, the mass ratio of ethylene carbonate to propylene carbonate is preferably 99: 1 to 40:60, and particularly preferably 95: 5 to 50:50. Further, the amount of propylene carbonate in the whole non-aqueous solvent is 1% by mass or more, preferably 2% by mass or more, more preferably 3% by mass or more, and the upper limit is usually 20% by mass or less, preferably 8% by mass or less. More preferably, it is 5 mass% or less. When propylene carbonate is contained in this range, it is preferable because the low temperature characteristics are further excellent while maintaining the combination characteristics of ethylene carbonate and alkyl carbonates.

<Saturated chain carbonate>
As a saturated chain carbonate, a C3-C7 thing is preferable.
Specifically, as the saturated chain carbonate having 3 to 7 carbon atoms, dimethyl carbonate, diethyl carbonate, di-n-propyl carbonate, diisopropyl carbonate, n-propyl isopropyl carbonate, ethyl methyl carbonate, methyl-n-propyl carbonate N-butyl methyl carbonate, isobutyl methyl carbonate, t-butyl methyl carbonate, ethyl n-propyl carbonate, n-butyl ethyl carbonate, isobutyl ethyl carbonate, t-butyl ethyl carbonate, and the like.

  Among them, dimethyl carbonate, diethyl carbonate, di-n-propyl carbonate, diisopropyl carbonate, n-propyl isopropyl carbonate, ethyl methyl carbonate, and methyl n-propyl carbonate are preferable, and dimethyl carbonate, diethyl carbonate, and ethyl methyl carbonate are particularly preferable. is there.

The blending amount of the saturated chain carbonate is preferably 5% by mass or more, more preferably 10% by mass or more, and further preferably 15% by mass or more in 100% by mass of the non-aqueous solvent. By setting the lower limit in this way, the viscosity of the non-aqueous electrolyte solution is set to an appropriate range, the decrease in ionic conductivity is suppressed, and the large current discharge characteristics of the non-aqueous electrolyte secondary battery are easily set to a favorable range. Become. Further, the saturated chain carbonate composed of carbon atoms, oxygen atoms and hydrogen atoms is preferably 95% by mass or less, more preferably 80% by mass or less, in 100% by mass of the non-aqueous solvent. By setting the upper limit in this way, it is easy to avoid a decrease in electrical conductivity due to a decrease in the dielectric constant of the non-aqueous electrolyte and to make the large current discharge characteristics of the non-aqueous electrolyte secondary battery in a favorable range. .

  A saturated chain carbonate may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and a ratio. A preferred example is the combined use of dimethyl carbonate and ethyl methyl carbonate. In this case, it is particularly preferable that the amount of dimethyl carbonate is 10% by mass to 70% by mass and the amount of ethyl methyl carbonate is 10% by mass to 80% by mass. It is also preferable to use dimethyl carbonate and diethyl carbonate in combination. The amount of dimethyl carbonate is 10% by mass or more and 70% by mass or less, and the amount of diethyl carbonate is 10% by mass or more and 70% by mass or less. Is particularly preferred. Further, when ethyl methyl carbonate and diethyl carbonate are used in combination, the amount of ethyl methyl carbonate is 10 mass% or more and 80 mass% or less, and the amount of diethyl carbonate is 10 mass% or more and 70 mass% or less. Some are particularly preferred.

<Cyclic carboxylic acid ester>
Examples of the cyclic carboxylic acid ester include those having 3 to 12 total carbon atoms in the structural formula.
Specific examples include gamma butyrolactone, gamma valerolactone, gamma caprolactone, epsilon caprolactone, and the like. Among these, gamma butyrolactone is particularly preferable from the viewpoint of improving battery characteristics resulting from an improvement in the degree of lithium ion dissociation.

  The compounding amount of the cyclic carboxylic acid ester is usually 5% by mass or more, more preferably 10% by mass or more, in 100% by mass of the non-aqueous solvent. By setting the lower limit in this manner, the electrical conductivity of the non-aqueous electrolyte solution is improved, and the large current discharge characteristics of the non-aqueous electrolyte secondary battery are easily improved. Moreover, the compounding quantity of cyclic carboxylic acid ester becomes like this. Preferably it is 40 mass% or less, More preferably, it is 35 mass% or less. By setting the upper limit in this way, the viscosity of the non-aqueous electrolyte solution is set to an appropriate range, the decrease in electrical conductivity is avoided, the increase in negative electrode resistance is suppressed, and the large current of the non-aqueous electrolyte secondary battery It becomes easy to make a discharge characteristic into a favorable range.

<Chain carboxylic acid ester>
Examples of the chain carboxylic acid ester include those having 3 to 7 carbon atoms in the structural formula.
Specifically, methyl acetate, ethyl acetate, acetic acid-n-propyl, isopropyl acetate, acetic acid-n-butyl, isobutyl acetate, acetic acid-t-butyl, methyl propionate, ethyl propionate, propionate-n-propyl, Isopropyl propionate, n-butyl propionate, isobutyl propionate, t-butyl propionate, methyl butyrate, ethyl butyrate, n-propyl butyrate, isopropyl butyrate, methyl isobutyrate, ethyl isobutyrate, isobutyric acid-n- Examples include propyl and isopropyl isobutyrate.

  Among them, methyl acetate, ethyl acetate, acetate-n-propyl acetate-n-butyl acetate, methyl propionate, ethyl propionate, propionate-n-propyl, isopropyl propionate, methyl butyrate, ethyl butyrate, etc. It is preferable from the viewpoint of improvement of ionic conductivity.

The compounding amount of the chain carboxylic acid ester is usually 5% by mass or more, more preferably 10% by mass or more, in 100% by mass of the non-aqueous solvent. By setting the lower limit in this way, the electrical conductivity of the non-aqueous electrolyte solution is improved, and the large current discharge characteristics of the non-aqueous electrolyte secondary battery are easily improved. Moreover, the compounding quantity of chain | strand-shaped carboxylic acid ester is in a nonaqueous solvent 100 mass%, Preferably it is 40 mass% or less, More preferably, it is 35 mass% or less. By setting the upper limit in this manner, an increase in negative electrode resistance is suppressed, and the large current discharge characteristics and cycle characteristics of the non-aqueous electrolyte secondary battery are easily set in a favorable range.

<Ether compound>
As the ether compound, a chain ether having 3 to 10 carbon atoms in which part of hydrogen may be substituted with fluorine, and a cyclic ether having 3 to 6 carbon atoms are preferable.
Examples of the chain ether having 3 to 10 carbon atoms include diethyl ether, di (2-fluoroethyl) ether, di (2,2-difluoroethyl) ether, di (2,2,2-trifluoroethyl) ether, ethyl (2-fluoroethyl) ether, ethyl (2,2,2-trifluoroethyl) ether, ethyl (1,1,2,2-tetrafluoroethyl) ether, (2-fluoroethyl) (2,2,2 -Trifluoroethyl) ether, (2-fluoroethyl) (1,1,2,2-tetrafluoroethyl) ether, (2,2,2-trifluoroethyl) (1,1,2,2-tetrafluoro) Ethyl) ether, ethyl-n-propyl ether, ethyl (3-fluoro-n-propyl) ether, ethyl (3,3,3-trifluoro-n-propyl) Ether, ethyl (2,2,3,3-tetrafluoro-n-propyl) ether, ethyl (2,2,3,3,3-pentafluoro-n-propyl) ether, 2-fluoroethyl-n-propyl Ether, (2-fluoroethyl) (3-fluoro-n-propyl) ether, (2-fluoroethyl) (3,3,3-trifluoro-n-propyl) ether, (2-fluoroethyl) (2, 2,3,3-tetrafluoro-n-propyl) ether, (2-fluoroethyl) (2,2,3,3,3-pentafluoro-n-propyl) ether, 2,2,2-trifluoroethyl -N-propyl ether, (2,2,2-trifluoroethyl) (3-fluoro-n-propyl) ether, (2,2,2-trifluoroethyl) (3,3,3-trifluoro Olo-n-propyl) ether, (2,2,2-trifluoroethyl) (2,2,3,3-tetrafluoro-n-propyl) ether, (2,2,2-trifluoroethyl) (2 , 2,3,3,3-pentafluoro-n-propyl) ether, 1,1,2,2-tetrafluoroethyl-n-propyl ether, (1,1,2,2-tetrafluoroethyl) (3 -Fluoro-n-propyl) ether, (1,1,2,2-tetrafluoroethyl) (3,3,3-trifluoro-n-propyl) ether, (1,1,2,2-tetrafluoroethyl) ) (2,2,3,3-tetrafluoro-n-propyl) ether, (1,1,2,2-tetrafluoroethyl) (2,2,3,3,3-pentafluoro-n-propyl) Ether, di-n-propyl Ether, (n-propyl) (3-fluoro-n-propyl) ether, (n-propyl) (3,3,3-trifluoro-n-propyl) ether, (n-propyl) (2,2,3 , 3-tetrafluoro-n-propyl) ether, (n-propyl) (2,2,3,3,3-pentafluoro-n-propyl) ether, di (3-fluoro-n-propyl) ether, ( 3-Fluoro-n-propyl) (3,3,3-trifluoro-n-propyl) ether, (3-fluoro-n-propyl) (2,2,3,3-tetrafluoro-n-propyl) ether , (3-fluoro-n-propyl) (2,2,3,3,3-pentafluoro-n-propyl) ether, di (3,3,3-trifluoro-n-propyl) ether, (3 3,3-triflu (Ro-n-propyl) (2,2,3,3-tetrafluoro-n-propyl) ether, (3,3,3-trifluoro-n-propyl) (2,2,3,3,3-penta Fluoro-n-propyl) ether, di (2,2,3,3-tetrafluoro-n-propyl) ether, (2,2,3,3-tetrafluoro-n-propyl) (2,2,3 3,3-pentafluoro-n-propyl) ether, di (2,2,3,3,3-pentafluoro-n-propyl) ether, di-n-butyl ether, dimethoxymethane, methoxyethoxymethane, methoxy (2 -Fluoroethoxy) methane, methoxy (2,2,2-trifluoroethoxy) methanemethoxy (1,1,2,2-tetrafluoroethoxy) methane, diethoxymethane, ethoxymethoxymeth , Ethoxy (2-fluoroethoxy) methane, ethoxy (2,2,2-trifluoroethoxy) methane, ethoxy (1,1,2,2-tetrafluoroethoxy) methane, di (2-fluoroethoxy) methane, (2-fluoroethoxy) (2,2,2-trifluoroethoxy) methane, (2-fluoroethoxy) (1,1,2,2-tetrafluoroethoxy) methanedi (2,2,2-trifluoroethoxy) Methane, (2,2,2-trifluoroethoxy) (1,1,2,2-tetrafluoroethoxy) methane, di (1,1,2,2-tetrafluoroethoxy) methane, dimethoxyethane, methoxyethoxyethane , Methoxy (2-fluoroethoxy) ethane, methoxy (2,2,2-trifluoroethoxy) ethane, methoxy (1,1,2, , 2-tetrafluoroethoxy) ethane, diethoxyethane, ethoxy (2-fluoroethoxy) ethane, ethoxy (2,2,2-trifluoroethoxy) ethane, ethoxy (1,1,2,2-tetrafluoroethoxy) Ethane, di (2-fluoroethoxy) ethane, (2-fluoroethoxy) (2,2,2-trifluoroethoxy) ethane, (2-fluoroethoxy) (1,1,2,2-tetrafluoroethoxy) ethane , Di (2,2,2-trifluoroethoxy) ethane, (2,2,2-trifluoroethoxy) (1,1,2,2-tetrafluoroethoxy) ethane, di (1,1,2,2) -Tetrafluoroethoxy) ethane, ethylene glycol di-n-propyl ether, ethylene glycol di-n-butyl ether, diethylene glycol Lumpur dimethyl ether, and the like.

  Examples of the cyclic ether having 3 to 6 carbon atoms include tetrahydrofuran, 2-methyltetrahydrofuran, 3-methyltetrahydrofuran, 1,3-dioxane, 2-methyl-1,3-dioxane, 4-methyl-1,3-dioxane, 1 , 4-dioxane and the like, and fluorinated compounds thereof.

  Among them, dimethoxymethane, diethoxymethane, ethoxymethoxymethane, ethylene glycol di-n-propyl ether, ethylene glycol di-n-butyl ether, and diethylene glycol dimethyl ether have high solvating ability to lithium ions and improve ion dissociation. Of these, dimethoxymethane, diethoxymethane, and ethoxymethoxymethane are preferable because they have low viscosity and give high ionic conductivity.

  The compounding amount of the ether-based compound is usually 5% by mass or more, preferably 10% by mass or more, more preferably 15% by mass or more, and preferably 40% by mass or less, in 100% by mass of the nonaqueous solvent. More preferably, it is 35 mass% or less, More preferably, it is 30 mass% or less. If it is this range, it is easy to ensure the improvement effect of the lithium ion dissociation degree of chain ether, and the improvement of the ionic conductivity derived from a viscosity fall, and when a negative electrode active material is a carbonaceous material, a chain ether with lithium ion It is easy to avoid a situation where the capacity is reduced due to co-insertion.

<Sulfone compound>
As the sulfone compound, a cyclic sulfone having 3 to 6 carbon atoms and a chain sulfone having 2 to 6 carbon atoms are preferable. The number of sulfonyl groups in one molecule is preferably 1 or 2.

  Examples of the cyclic sulfone include trimethylene sulfones, tetramethylene sulfones, and hexamethylene sulfones that are monosulfone compounds; trimethylene disulfones, tetramethylene disulfones, and hexamethylene disulfones that are disulfone compounds. Among these, from the viewpoint of dielectric constant and viscosity, tetramethylene sulfones, tetramethylene disulfones, hexamethylene sulfones, and hexamethylene disulfones are more preferable, and tetramethylene sulfones (sulfolanes) are particularly preferable.

The sulfolane is preferably sulfolane and / or a sulfolane derivative (hereinafter sometimes abbreviated as “sulfolane” including sulfolane). As the sulfolane derivative, one in which one or more hydrogen atoms bonded to the carbon atom constituting the sulfolane ring are substituted with a fluorine atom or an alkyl group is preferable.

  Among them, 2-methylsulfolane, 3-methylsulfolane, 2-fluorosulfolane, 3-fluorosulfolane, 2,2-difluorosulfolane, 2,3-difluorosulfolane, 2,4-difluorosulfolane, 2,5-difluorosulfolane, 3,4-difluorosulfolane, 2-fluoro-3-methylsulfolane, 2-fluoro-2-methylsulfolane, 3-fluoro-3-methylsulfolane, 3-fluoro-2-methylsulfolane, 4-fluoro-3-methyl Sulfolane, 4-fluoro-2-methylsulfolane, 5-fluoro-3-methylsulfolane, 5-fluoro-2-methylsulfolane, 2-fluoromethylsulfolane, 3-fluoromethylsulfolane, 2-difluoromethylsulfolane, 3-difluoro Methyl sulfolane, 2- Trifluoromethylsulfolane, 3-trifluoromethylsulfolane, 2-fluoro-3- (trifluoromethyl) sulfolane, 3-fluoro-3- (trifluoromethyl) sulfolane, 4-fluoro-3- (trifluoromethyl) sulfolane , 5-fluoro-3- (trifluoromethyl) sulfolane and the like are preferable in terms of high ionic conductivity and high input / output.

  As the chain sulfone, dimethyl sulfone, ethyl methyl sulfone, diethyl sulfone, n-propyl methyl sulfone, n-propyl ethyl sulfone, di-n-propyl sulfone, isopropyl methyl sulfone, isopropyl ethyl sulfone, diisopropyl sulfone, n- Butyl methyl sulfone, n-butyl ethyl sulfone, t-butyl methyl sulfone, t-butyl ethyl sulfone, monofluoromethyl methyl sulfone, difluoromethyl methyl sulfone, trifluoromethyl methyl sulfone, monofluoroethyl methyl sulfone, difluoroethyl methyl sulfone, Trifluoroethyl methyl sulfone, pentafluoroethyl methyl sulfone, ethyl monofluoromethyl sulfone, ethyl difluoromethyl sulfone, ethyl trif Oromethylsulfone, perfluoroethylmethylsulfone, ethyltrifluoroethylsulfone, ethylpentafluoroethylsulfone, di (trifluoroethyl) sulfone, perfluorodiethylsulfone, fluoromethyl-n-propylsulfone, difluoromethyl-n-propylsulfone Trifluoromethyl-n-propylsulfone, fluoromethylisopropylsulfone, difluoromethylisopropylsulfone, trifluoromethylisopropylsulfone, trifluoroethyl-n-propylsulfone, trifluoroethylisopropylsulfone, pentafluoroethyl-n-propylsulfone, Pentafluoroethyl isopropyl sulfone, trifluoroethyl-n-butyl sulfone, trifluoroethyl-t-butyl sulfone Emissions, pentafluoroethyl -n- butyl sulfone, pentafluoroethyl -t- butyl sulfone, and the like.

  Among them, dimethyl sulfone, ethyl methyl sulfone, diethyl sulfone, n-propyl methyl sulfone, isopropyl methyl sulfone, n-butyl methyl sulfone, t-butyl methyl sulfone, monofluoromethyl methyl sulfone, difluoromethyl methyl sulfone, trifluoromethyl methyl sulfone , Monofluoroethyl methyl sulfone, difluoroethyl methyl sulfone, trifluoroethyl methyl sulfone, pentafluoroethyl methyl sulfone, ethyl monofluoromethyl sulfone, ethyl difluoromethyl sulfone, ethyl trifluoromethyl sulfone, ethyl trifluoroethyl sulfone, ethyl pentafluoro Ethyl sulfone, trifluoromethyl-n-propyl sulfone, trifluoromethyl isopropyl sulfone, tri Ruoroechiru -n- butyl sulfone, trifluoroethyl -t- butyl sulfone, trifluoromethyl -n- butyl sulfone, trifluoromethyl -t- butyl sulfone is preferred because high output is high ionic conductivity.

The amount of the sulfone compound is usually in 100% by mass of the non-aqueous solvent, preferably 0.3% by mass or more, more preferably 0.5% by mass or more, further preferably 1% by mass or more, and preferably Is 40% by mass or less, more preferably 35% by mass or less, and still more preferably 30% by mass or less. Within this range, durability improvement effects such as cycle characteristics and storage characteristics can be easily obtained, and the viscosity of the non-aqueous electrolyte can be set to an appropriate range to avoid a decrease in electrical conductivity. When charging / discharging an aqueous electrolyte secondary battery at a high current density, it is easy to avoid a situation in which the charge / discharge capacity retention rate decreases.

1-3. Carbonate Having Fluorine Atom The nonaqueous electrolytic solution of the present invention is characterized by containing a carbonate having a fluorine atom. In addition, if it is a carbonate which has a fluorine atom, it will not be limited, A chain | strand shape or cyclic | annular form may be sufficient. However, the compound represented by the general formula (1) is not included in this. Examples of the carbonate having a fluorine atom include a saturated cyclic carbonate having a fluorine atom, a saturated chain carbonate having a fluorine atom, an unsaturated cyclic carbonate having a fluorine atom, and an unsaturated chain carbonate having a fluorine atom.

<Saturated cyclic carbonate having fluorine atom>
The saturated cyclic carbonate having a fluorine atom (hereinafter also referred to as fluorinated saturated cyclic carbonate) is not particularly limited, and examples thereof include saturated cyclic carbonate derivatives having an alkylene group having 2 to 6 carbon atoms. Includes ethylene carbonate derivatives. Examples of the ethylene carbonate derivative include fluorinated products of ethylene carbonate or ethylene carbonate substituted with an alkyl group (for example, an alkyl group having 1 to 4 carbon atoms), and among them, those having 1 to 8 fluorine atoms. preferable.

  Specifically, monofluoroethylene carbonate, 4,4-difluoroethylene carbonate, 4,5-difluoroethylene carbonate, 4-fluoro-4-methylethylene carbonate, 4,5-difluoro-4-methylethylene carbonate, 4- Fluoro-5-methylethylene carbonate, 4,4-difluoro-5-methylethylene carbonate, 4- (fluoromethyl) -ethylene carbonate, 4- (difluoromethyl) -ethylene carbonate, 4- (trifluoromethyl) -ethylene carbonate 4- (fluoromethyl) -4-fluoroethylene carbonate, 4- (fluoromethyl) -5-fluoroethylene carbonate, 4-fluoro-4,5-dimethylethylene carbonate, 4,5-difluoro-4,5-dimethyl Le ethylene carbonate, 4,4-difluoro-5,5-dimethylethylene carbonate.

  Among them, at least one selected from the group consisting of monofluoroethylene carbonate, 4,4-difluoroethylene carbonate, 4,5-difluoroethylene carbonate, and 4,5-difluoro-4,5-dimethylethylene carbonate has high ionic conductivity. It is more preferable in terms of imparting properties and suitably forming an interface protective film.

  Moreover, the fluorinated saturated cyclic carbonate mentioned above may be used individually by 1 type, and may have 2 or more types together by arbitrary combinations and ratios.

<Saturated chain carbonate having fluorine atom>
A saturated chain carbonate having a fluorine atom (hereinafter also referred to as a fluorinated saturated chain carbonate) can be preferably used. The number of fluorine atoms contained in the fluorinated chain carbonate is not particularly limited as long as it is 1 or more, but is usually 6 or less, preferably 4 or less. When the fluorinated saturated chain carbonate has a plurality of fluorine atoms, they may be bonded to the same carbon or may be bonded to different carbons. Examples of the fluorinated saturated chain carbonate include fluorinated dimethyl carbonate derivatives, fluorinated ethyl methyl carbonate derivatives, and fluorinated diethyl carbonate derivatives.

  Examples of the fluorinated dimethyl carbonate derivative include fluoromethyl methyl carbonate, difluoromethyl methyl carbonate, trifluoromethyl methyl carbonate, bis (fluoromethyl) carbonate, bis (difluoro) methyl carbonate, bis (trifluoromethyl) carbonate, and the like.

  Fluorinated ethyl methyl carbonate derivatives include 2-fluoroethyl methyl carbonate, ethyl fluoromethyl carbonate, 2,2-difluoroethyl methyl carbonate, 2-fluoroethyl fluoromethyl carbonate, ethyl difluoromethyl carbonate, 2,2,2-trimethyl Examples include fluoroethyl methyl carbonate, 2,2-difluoroethyl fluoromethyl carbonate, 2-fluoroethyl difluoromethyl carbonate, and ethyl trifluoromethyl carbonate.

  Fluorinated diethyl carbonate derivatives include ethyl- (2-fluoroethyl) carbonate, ethyl- (2,2-difluoroethyl) carbonate, bis (2-fluoroethyl) carbonate, ethyl- (2,2,2-trifluoro). Ethyl) carbonate, 2,2-difluoroethyl-2′-fluoroethyl carbonate, bis (2,2-difluoroethyl) carbonate, 2,2,2-trifluoroethyl-2′-fluoroethyl carbonate, 2,2, Examples include 2-trifluoroethyl-2 ′, 2′-difluoroethyl carbonate, bis (2,2,2-trifluoroethyl) carbonate, and the like.

  Among these, as the fluorinated saturated chain carbonate, 2,2,2-trifluoroethyl methyl carbonate and bis (2,2,2-trifluoroethyl) carbonate are particularly preferable.

  Moreover, the fluorinated saturated chain carbonate mentioned above may be used individually by 1 type, and may have 2 or more types by arbitrary combinations and ratios.

<Unsaturated cyclic carbonate having a fluorine atom>
Of the carbonates having fluorine atoms, unsaturated cyclic carbonates having fluorine atoms (hereinafter also referred to as fluorinated unsaturated cyclic carbonates) can be suitably used. Examples of the fluorinated unsaturated cyclic carbonate include a fluorinated vinylene carbonate derivative, a fluorinated ethylene carbonate derivative substituted with a substituent having an aromatic ring or a carbon-carbon unsaturated bond, and the like.

  Fluorinated vinylene carbonate derivatives include 4-fluoro vinylene carbonate, 4-fluoro-5-methyl vinylene carbonate, 4-fluoro-5-phenyl vinylene carbonate, 4-allyl-5-fluoro vinylene carbonate, 4-fluoro-5- Examples include vinyl vinylene carbonate, 4-fluoro-5-vinyl vinylene carbonate, 4-allyl-5-fluoro vinylene carbonate, and the like.

Examples of the fluorinated ethylene carbonate derivative substituted with an aromatic ring or a substituent having a carbon-carbon unsaturated bond include 4-fluoro-4-vinylethylene carbonate, 4-fluoro-4-allylethylene carbonate, 4-fluoro-5. -Vinylethylene carbonate, 4-fluoro-5-allylethylene carbonate, 4,4-difluoro-5-vinylethylene carbonate, 4,4-difluoro-5-allylethylene carbonate, 4,5-difluoro-4-vinylethylene carbonate 4,5-difluoro-4-allylethylene carbonate, 4-fluoro-4,5-divinylethylene carbonate, 4-fluoro-4,5-diallylethylene carbonate, 4,5-difluoro-4,5-divinylethylene carbonate , 4,5-Diff Oro-4,5-diallylethylene carbonate, 4-fluoro-4-phenylethylene carbonate, 4-fluoro-5-phenylethylene carbonate, 4,4-difluoro-5-phenylethylene carbonate, 4,5-difluoro-4- Examples thereof include phenylethylene carbonate.

  Examples of the fluorinated unsaturated cyclic carbonate include 4-fluoro-4-vinylethylene carbonate, 4-fluoro-4-allylethylene carbonate, 4-fluoro-5-vinylethylene carbonate, 4-fluoro-5-allylethylene carbonate, 4 , 4-Difluoro-5-vinylethylene carbonate, 4,4-difluoro-5-allylethylene carbonate, 4,5-difluoro-4-vinylethylene carbonate, 4,5-difluoro-4-allylethylene carbonate, 4-fluoro -4,5-divinylethylene carbonate, 4-fluoro-4,5-diallylethylene carbonate, 4,5-difluoro-4,5-divinylethylene carbonate, 4,5-difluoro-4,5-diallylethylene carbonate are preferred. . Since these form a stable interface protective film, they are more preferably used.

  Moreover, a fluorinated unsaturated cyclic carbonate may be used individually by 1 type, and may have 2 or more types by arbitrary combinations and ratios.

<Unsaturated linear carbonate having a fluorine atom>
Among carbonates having fluorine atoms, unsaturated chain carbonates having fluorine atoms (hereinafter also referred to as fluorinated unsaturated chain carbonates) can be suitably used. Examples of the fluorinated unsaturated chain carbonate include 1-fluorovinyl methyl carbonate, 2-fluorovinyl methyl carbonate, 1,2-difluorovinyl methyl carbonate, ethyl-1-fluorovinyl carbonate, ethyl-2-fluorovinyl carbonate, ethyl -1,2-difluorovinyl carbonate, bis (1-fluorovinyl) carbonate, bis (2-fluorovinyl) carbonate, bis (1,2-difluorovinyl) carbonate, 1-fluoro-1-propenylmethyl carbonate, 2- Fluoro-1-propenyl methyl carbonate, 3-fluoro-1-propenyl methyl carbonate, 1,2-difluoro-1-propenyl methyl carbonate, 1,3-difluoro-1-propenyl methyl carbonate, 2 3-difluoro-1-propenylmethyl carbonate, 3,3-difluoro-1-propenylmethyl carbonate, 1-fluoro-2-propenylmethyl carbonate, 2-fluoro-2-propenylmethyl carbonate, 3-fluoro-2-propenylmethyl Carbonate, 1,1-difluoro-2-propenylmethyl carbonate, 1,2-difluoro-2-propenylmethyl carbonate, 1,3-difluoro-2-propenylmethyl carbonate, 2,3-difluoro-2-propenylmethyl carbonate, Examples include fluoroethynyl methyl carbonate, 3-fluoro-1-propynyl methyl carbonate, 1-fluoro-2-propynyl methyl carbonate, 3-fluoro-2-propynyl methyl carbonate, and the like.

  Moreover, a fluorinated unsaturated chain carbonate may be used individually by 1 type, and may have 2 or more types by arbitrary combinations and ratios.

  The molecular weight of the carbonate having a fluorine atom is not particularly limited, and is arbitrary as long as the effects of the present invention are not significantly impaired. If it is this range, it will be easy to ensure the solubility of the compound represented by General formula (1) with respect to a non-aqueous electrolyte, and the effect of this invention will fully be expressed easily.

  The blending amount in the case of using a carbonate having a fluorine atom is preferably 0.01% by mass or more, more preferably 0.1% by mass or more, and further preferably 0.2% by mass or more, in 100% by mass of the non-aqueous electrolyte solution. It is preferably 90% by mass or less, more preferably 85% by mass or less, still more preferably 80% by mass or less, and most preferably less than 50% by mass.

  In particular, when a carbonate having a fluorine atom plays a role as a solvent, the blending amount thereof is preferably 5% by mass or more, more preferably 7% by mass or more, and further preferably 10% by mass in 100% by mass of the nonaqueous electrolytic solution. % Or more, preferably 90% by mass or less, more preferably 70% by mass or less, still more preferably 50% by mass or less, and most preferably less than 50% by mass. Within this range, when the battery is operated at a high voltage, the secondary decomposition reaction of the non-aqueous electrolyte can be suppressed, the battery durability can be improved, and the electrical conductivity of the non-aqueous electrolyte is extremely reduced. Can be prevented. In the case of fulfilling the role as a solvent, among the carbonates having a fluorine atom, a fluorinated saturated cyclic or chain carbonate is preferable.

  On the other hand, when the carbonate having a fluorine atom plays a role as an auxiliary agent, the blending amount thereof is 100% by mass of the non-aqueous electrolyte solution, preferably 0.01% by mass or more, more preferably 0.1% by mass. More preferably, the content is 0.2% by mass or more, preferably 5% by mass or less, more preferably 4% by mass or less, and still more preferably 3% by mass or less. Within this range, since the durability can be improved without excessively increasing the charge transfer resistance, the charge / discharge durability at a high current density can be improved. When serving as an auxiliary agent, it is preferable to use at least one of fluorinated saturated carbonate, fluorinated unsaturated cyclic or chain carbonate among the above-mentioned carbonates having fluorine atoms.

  Although the role of the carbonate having a fluorine atom as the solvent and auxiliary agent has been described above, there is no clear boundary line in the solvent or auxiliary agent when actually used, and a nonaqueous electrolytic solution can be prepared at an arbitrary ratio. Shall.

Moreover, regarding the above-mentioned fluorinated saturated cyclic carbonate, battery performance can be remarkably improved by combining the saturated cyclic / chain carbonate with a specific blending amount.
For example, when monofluoroethylene carbonate is selected as the fluorinated saturated cyclic carbonate and dimethyl carbonate, ethylmethyl carbonate, or diethyl carbonate is selected as the saturated chain carbonate, the lower limit of the blending amount of monofluoroethylene carbonate is: It is preferably 10% by mass or more, and the blending amount of dimethyl carbonate, ethyl methyl carbonate, or diethyl carbonate is preferably 50% by mass or more and 90% by mass or less.

  It is also preferable to use two or more kinds of fluorinated saturated cyclic carbonate and saturated chain carbonate in combination. For example, when monofluoroethylene carbonate is selected as the fluorinated saturated cyclic carbonate and dimethyl carbonate and ethyl methyl carbonate are selected as the saturated chain carbonate, the lower limit of the blending amount of monofluoroethylene carbonate is 10% by mass or more, The blending amount of dimethyl carbonate is preferably 10% by mass or more and 70% by mass or less, and the blending amount of ethyl methyl carbonate is preferably 10% by mass or more and 80% by mass or less.

Similarly, when dimethyl carbonate and diethyl carbonate are selected as the saturated chain carbonate, the lower limit of the amount of monofluoroethylene carbonate is 10% by mass or more, and the amount of dimethyl carbonate is 10% by mass or more and 80% by mass. Hereinafter, it is preferable that the compounding quantity of diethyl carbonate is 10 mass% or more and 80 mass% or less.
Similarly, when ethyl methyl carbonate and diethyl carbonate are selected as the saturated chain carbonate, the lower limit of the amount of monofluoroethylene carbonate is 10% by mass or more, and the amount of ethyl methyl carbonate is 10% by mass or more 80%. It is preferable that the blending amount of diethyl carbonate is 10% by mass or more and 70% by mass or less.

  By selecting such a blending amount, the low-temperature deposition temperature of the electrolyte is lowered, the viscosity of the nonaqueous electrolytic solution is also lowered to improve the ionic conductivity, and a high output can be obtained even at a low temperature.

  In addition, it is also preferable to add ethylene carbonate to the saturated cyclic carbonate in the above composition. For example, when monofluoroethylene carbonate, ethylene carbonate, dimethyl carbonate and ethyl methyl carbonate are selected, the lower limit of the amount of monofluoroethylene carbonate is 0.01% by mass or more, and the amount of ethylene carbonate is 5% by mass. It is particularly preferable that the amount of dimethyl carbonate is 10% by mass to 50% by mass and the amount of ethyl methyl carbonate is 10% by mass to 70% by mass.

1-4. Compound Represented by General Formula (1) The present invention is characterized by containing a compound represented by the following general formula (1) in a non-aqueous electrolyte solution.

In the general formula (1), X and Z represent CR ¹ ₂ , C═O, C═N—R ¹ , C═P—R ¹ , O, S, N—R ¹ , P—R ¹ , It may be the same or different. Y represents CR ¹ ₂ , C═O, S═O, S (═O) ₂ , P (═O) —R ² , P (═O) —OR ³ . In the general formula (1), R and R ¹ are hydrogen, halogen, or an optionally substituted hydrocarbon group having 1 to 20 carbon atoms, which may be the same or different from each other. . R ² is an optionally substituted hydrocarbon group having 1 to 20 carbon atoms. R ³ is Li, NR ⁴ ₄ or a hydrocarbon group having 1 to 20 carbon atoms which may have a substituent. R ⁴ is a hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and may be the same or different. n and m represent an integer of 0 or more. In addition, carbons in adjacent rings may form further bonds with each other, and R of the carbons may be reduced by one each. W is the same as R.

In the general formula (1), X and Z have the general formula (1) is not particularly limited as long as the scope of the described, _{^{preferably, CR 1 2, O, S}} , N-R are more preferred. Y is not particularly limited as long as it is within the range described in the general formula (1), but preferably C═O, S═O, S (═O) ₂ , P (═O) —R ² , P ( ═O) —OR ³ is more preferred.

R and R ¹ are not particularly limited as long as they are within the range described in the general formula (1), but preferably have hydrogen, fluorine, a saturated aliphatic hydrocarbon group which may have a substituent, or a substituent. Examples thereof may include an unsaturated aliphatic hydrocarbon group which may be substituted, and an aromatic hydrocarbon group which may have a substituent.
R ² and R ⁴ are not particularly limited as long as they are within the range described in the general formula (1), but are preferably a saturated aliphatic hydrocarbon group that may have a substituent or a substituent. Examples thereof include an unsaturated aliphatic hydrocarbon group and an aromatic hydrocarbon / aromatic heterocycle which may have a substituent.
R ³ is not particularly limited as long as it is within the range described in the general formula (1), but preferably Li, a saturated aliphatic hydrocarbon group which may have a substituent, or a group which may have a substituent. Examples thereof include saturated aliphatic hydrocarbon groups and aromatic hydrocarbon groups and aromatic heterocycles which may have a substituent.

  A saturated aliphatic hydrocarbon group that may have a substituent, an unsaturated aliphatic hydrocarbon group that may have a substituent, an aromatic hydrocarbon group that may have a substituent, and an aromatic heterocyclic ring. The substituent is not particularly limited, but preferably includes halogen, carboxylic acid, carbonic acid, sulfonic acid, phosphoric acid, phosphorous acid, and the like, more preferably halogen, and most preferably fluorine.

  Specific preferred saturated aliphatic hydrocarbon groups are methyl, ethyl, fluoromethyl, difluoromethyl, trifluoromethyl, 1-fluoroethyl, 2-fluoroethyl, 1,1-difluoro. Ethyl group, 1,2-difluoroethyl group, 2,2-difluoroethyl group, 1,1,2-trifluoroethyl group, 1,2,2-trifluoroethyl group, 2,2,2-trifluoroethyl Examples thereof include a phenyl group, a cyclopentyl group, and a cyclohexyl group.

Specific preferred unsaturated aliphatic hydrocarbon groups are ethenyl, 1-fluoroethenyl, 2-fluoroethenyl, 1-methylethenyl, 2-propenyl, 2-fluoro-2-propenyl. Group, 3-fluoro-2-propenyl group, ethynyl group, 2-fluoroethynyl group, 2-propynyl group and 3-fluoro-2propynyl group.
Preferred aromatic hydrocarbon groups include phenyl group, 2-fluorophenyl group, 3-fluorophenyl group, 2,4-difluorophenyl group, 2,6-difluorophenyl group, 3,5-difluorophenyl group, 2, Examples include 4,6-trifluorophenyl group.

Preferable aromatic heterocycle includes 2-furanyl group, 3-furanyl group, 2-thiophenyl group, 3-thiophenyl group, 1-methyl-2-pyrrolyl group, and 1-methyl-3-pyrrolyl group.
Among these, a methyl group, an ethyl group, a fluoromethyl group, a trifluoromethyl group, a 2-fluoroethyl group, a 2,2,2-trifluoroethyl group, an ethenyl group, an ethynyl group, and a phenyl group are exemplified. More preferred are a methyl group, an ethyl group, and an ethynyl group.

n and m are not particularly limited as long as they are within the range described in the general formula (1), but are preferably 0 or 1, and more preferably n = m = 1 or n = 1 and m = 0.
The molecular weight is preferably 50 or more. Moreover, Preferably, it is 500 or less. If it is this range, it will be easy to ensure the solubility of the unsaturated cyclic carbonate with respect to a non-aqueous electrolyte solution, and the effect of this invention will fully be expressed easily.

  Preferable specific examples of the compound represented by the general formula (1) include the compounds described below.

  Among these, it is preferable that R is hydrogen, a fluorine, or an ethynyl group from both the reactivity and the stability. In the case of other substituents, the reactivity is lowered, and the expected properties may be lowered. Moreover, when it is halogen other than fluorine, there is a possibility that the reactivity is too high and the side reaction increases.

  The number of fluorine or ethynyl groups in R is preferably within 2 in total. If the number is too large, the compatibility with the electrolytic solution may be deteriorated, and the reactivity may be too high to increase the side reaction.

  Among these, n = 1 and m = 0 are preferable. When both are 0, stability deteriorates from the distortion of the ring, the reactivity becomes too high, and there is a possibility that side reactions increase. Further, even if n = 2 or more, or n = 1, when m = 1 or more, there is a possibility that the chain is more stable than the ring and the initial characteristics may not be exhibited.

Further, in the general formula (1), X and Z are, CR ¹ ₂ or O are more preferred. In cases other than these, the reactivity may be too high and side reactions may increase.

  The molecular weight is more preferably 100 or more, and more preferably 200 or less. If it is this range, it will be easy to ensure further the solubility of General formula (1) with respect to a non-aqueous electrolyte solution, and the effect of this invention will be further fully expressed easily.

  Specific examples of these more preferable compounds include the compounds described below.

More preferably, R is all hydrogen. In this case, the side reaction is most likely to be suppressed while maintaining the expected characteristics. Further, when Y is C═O or S═O, one of X and Z is O, indicating that Y is S (═O) ₂ , P (═O) —R ² , P (═O In the case of —OR ³ , it is preferable that both X and Z are O or CH ₂ , or one of X and Z is O and the other is CH ₂ . When Y is C═O or S═O, if both X and Z are CH ₂ , the reactivity may be too high and side reactions may increase.

  Specific examples of these compounds include the compounds described below.

  On the other hand, the compound represented by the general formula (2) is preferable from the viewpoint of ease of industrial production.

In the general formula (2), Y represents C═O, S═O, S (═O) ₂ , P (═O) —R ² , P (═O) —OR ³ . R ² is an optionally substituted hydrocarbon group having 1 to 20 carbon atoms. R ³ is Li, NR ⁴ ₄ or a hydrocarbon group having 1 to 20 carbon atoms which may have a substituent. R ⁴ is a hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and may be the same or different.

  Specific examples of these compounds having preferable conditions include the following compounds.

The compound represented by General formula (1) may be used individually by 1 type, or may have 2 or more types by arbitrary combinations and ratios. Moreover, the compounding quantity of the compound represented by General formula (1) is not restrict | limited in particular, As long as the effect of this invention is not impaired remarkably, it is arbitrary. The compounding amount of the compound represented by the general formula (1) is preferably 0.001% by mass or more, more preferably 0.01% by mass or more, and further preferably 0.1% by mass in 100% by mass of the non-aqueous solvent. Further, it is preferably 5% by mass or less, more preferably 4% by mass or less, and further preferably 3% by mass or less. Within this range, the non-aqueous electrolyte secondary battery is likely to exhibit a sufficient cycle characteristics improvement effect, and the high-temperature storage characteristics are reduced, the amount of gas generated is increased, and the discharge capacity maintenance rate is reduced. Easy to avoid. On the other hand, if the amount is too small, the effects of the present invention may not be sufficiently exerted. If the amount is too large, the resistance may increase and the output and load characteristics may decrease.

  Moreover, the ratio of the compounding quantity of the carbonate which has a fluorine atom, and the compound represented by General formula (1) is although it does not specifically limit, The total content mass of the carbonate which has a fluorine atom is [A], General formula (1) When the total content of the compounds represented is [B], the upper limit of [B] / [A] is usually 100 or less, preferably 20 or less, more preferably 10 or less, and even more preferably 5 or less. Yes, the lower limit is usually 0.0001 or more, preferably 0.05 or more, more preferably 0.1 or more.

1-5. Auxiliary Agent In the non-aqueous electrolyte battery of the present invention, an auxiliary agent may be appropriately used depending on the purpose in addition to the saturated cyclic carbonate having a fluorine atom and the compound represented by the general formula (1). Examples of auxiliary agents include cyclic carbonates having an unsaturated bond shown below, overcharge inhibitors, other auxiliary agents, and the like.

<Cyclic carbonate having an unsaturated bond>
In the non-aqueous electrolyte solution of the present invention, in order to form a film on the negative electrode surface of the non-aqueous electrolyte battery and to extend the life of the battery, the cyclic carbonate having fluorine atoms and the general formula (1) are used. In addition to the compound, a cyclic carbonate having an unsaturated bond excluding the compound of the general formula (1) (hereinafter also referred to as an unsaturated cyclic carbonate) can be used.

The unsaturated cyclic carbonate is not particularly limited as long as it is a cyclic carbonate having a carbon-carbon double bond, and any unsaturated carbonate can be used. The cyclic carbonate having an aromatic ring is also included in the unsaturated cyclic carbonate.
Examples of the unsaturated cyclic carbonate include vinylene carbonates, ethylene carbonates substituted with a substituent having an aromatic ring or a carbon-carbon double bond, phenyl carbonates, vinyl carbonates, allyl carbonates, catechol carbonates, and the like. It is done.

  As vinylene carbonates, vinylene carbonate, methyl vinylene carbonate, 4,5-dimethyl vinylene carbonate, phenyl vinylene carbonate, 4,5-diphenyl vinylene carbonate, vinyl vinylene carbonate, 4,5-vinyl vinylene carbonate, allyl vinylene carbonate, 4 , 5-diallyl vinylene carbonate and the like.

  Specific examples of ethylene carbonates substituted with an aromatic ring or a substituent having a carbon-carbon double bond include vinyl ethylene carbonate, 4,5-divinyl ethylene carbonate, 4-methyl-5-vinyl ethylene carbonate, 4- Allyl-5-vinylethylene carbonate, phenylethylene carbonate, 4,5-diphenylethylene carbonate, 4-phenyl-5-vinylethylene carbonate, 4-allyl-5-phenylethylene carbonate, allylethylene carbonate, 4,5-diallylethylene Examples thereof include carbonate and 4-methyl-5-allylethylene carbonate.

Among them, particularly preferable unsaturated cyclic carbonates for use in combination with the compound of the general formula (1) include vinylene carbonate, methyl vinylene carbonate, 4,5-dimethyl vinylene carbonate, vinyl vinylene carbonate, 4,5-vinyl vinylene carbonate, Allyl vinylene carbonate, 4,5-diallyl vinylene carbonate, vinyl ethylene carbonate, 4,5-divinyl ethylene carbonate, 4-methyl-5-vinyl ethylene carbonate, allyl ethylene carbonate, 4,5-diallyl ethylene carbonate, 4-methyl- Since 5-allylethylene carbonate and 4-allyl-5-vinylethylene carbonate form a stable interface protective film, they are more preferably used.

  The molecular weight of the unsaturated cyclic carbonate is not particularly limited and is arbitrary as long as the effects of the present invention are not significantly impaired. The molecular weight is preferably 50 or more and 250 or less. If it is this range, it will be easy to ensure the solubility of the unsaturated cyclic carbonate with respect to a non-aqueous electrolyte solution, and the effect of this invention will fully be expressed easily. The molecular weight of the unsaturated cyclic carbonate is more preferably 80 or more, and more preferably 150 or less. The production method of the unsaturated cyclic carbonate is not particularly limited, and can be produced by arbitrarily selecting a known method.

  An unsaturated cyclic carbonate may be used individually by 1 type, or may have 2 or more types by arbitrary combinations and ratios. Moreover, the compounding quantity of unsaturated cyclic carbonate is not restrict | limited in particular, As long as the effect of this invention is not impaired remarkably, it is arbitrary. The blending amount of the unsaturated cyclic carbonate is preferably 0.001% by mass or more, more preferably 0.01% by mass or more, and further preferably 0.1% by mass or more, in 100% by mass of the non-aqueous solvent. Preferably, it is 5 mass% or less, More preferably, it is 4 mass% or less, More preferably, it is 3 mass% or less. Within this range, the non-aqueous electrolyte secondary battery is likely to exhibit a sufficient cycle characteristics improvement effect, and the high-temperature storage characteristics are reduced, the amount of gas generated is increased, and the discharge capacity maintenance rate is reduced. Easy to avoid. On the other hand, if the amount is too small, the effects of the present invention may not be sufficiently exhibited. If the amount is too large, the resistance may increase and the output and load characteristics may decrease.

<Overcharge prevention agent>
In the non-aqueous electrolyte solution of the present invention, an overcharge inhibitor can be used in order to effectively suppress battery explosion / ignition when the non-aqueous electrolyte secondary battery is in an overcharged state or the like. .

  As an overcharge inhibitor, aromatic compounds such as biphenyl, alkylbiphenyl, terphenyl, partially hydrogenated terphenyl, cyclohexylbenzene, t-butylbenzene, t-amylbenzene, diphenyl ether, dibenzofuran; 2-fluorobiphenyl, Partially fluorinated products of the above aromatic compounds such as o-cyclohexylfluorobenzene and p-cyclohexylfluorobenzene; 2,4-difluoroanisole, 2,5-difluoroanisole, 2,6-difluoroanisole, 3,5-difluoroanisole and the like And a fluorine-containing anisole compound. Of these, aromatic compounds such as biphenyl, alkylbiphenyl, terphenyl, terphenyl partially hydrogenated, cyclohexylbenzene, t-butylbenzene, t-amylbenzene, diphenyl ether, and dibenzofuran are preferable. These may be used alone or in combination of two or more. When two or more kinds are used in combination, in particular, a combination of cyclohexylbenzene and t-butylbenzene or t-amylbenzene, biphenyl, alkylbiphenyl, terphenyl, partially hydrogenated terphenyl, cyclohexylbenzene, t-butylbenzene, Using at least one selected from aromatic compounds not containing oxygen, such as t-amylbenzene, and at least one selected from oxygen-containing aromatic compounds such as diphenyl ether, dibenzofuran, and the like is an overcharge prevention property and a high temperature storage property. From the standpoint of balance.

The amount of the overcharge inhibitor is not particularly limited, and is arbitrary as long as the effects of the present invention are not significantly impaired. The overcharge inhibitor is preferably 0.01% by mass or more and 5% by mass or less in 100% by mass of the non-aqueous solvent. If it is this range, it will be easy to fully express the effect of an overcharge inhibiting agent, and it will be easy to avoid the situation where the battery characteristics, such as a high temperature storage characteristic, fall. The overcharge inhibitor is more preferably 0.01% by mass or more, further preferably 0.1% by mass or more, particularly preferably 0.2% by mass or more, and more preferably 3% by mass or less, still more preferably. Is 2% by mass or less.

<Other auxiliaries>
Other known auxiliary agents can be used in the non-aqueous electrolyte solution of the present invention. Other auxiliaries include carbonate compounds such as erythritan carbonate, spiro-bis-dimethylene carbonate, methoxyethyl-methyl carbonate; succinic anhydride, glutaric anhydride, maleic anhydride, citraconic anhydride, glutaconic anhydride, anhydrous Carboxylic anhydrides such as itaconic acid, diglycolic anhydride, cyclohexanedicarboxylic anhydride, cyclopentanetetracarboxylic dianhydride and phenylsuccinic anhydride; 2,4,8,10-tetraoxaspiro [5.5 ] Spiro compounds such as undecane, 3,9-divinyl-2,4,8,10-tetraoxaspiro [5.5] undecane; ethylene sulfite, 1,3-propane sultone, 1-fluoro-1,3- Propane sultone, 2-fluoro-1,3-propane sultone, 3-ph Oro-1,3-propane sultone, 1-propene-1,3-sultone, 1-fluoro-1-propene-1,3-sultone, 2-fluoro-1-propene-1,3-sultone, 3-fluoro -1-propene-1,3-sultone, 1,4-butanesultone, 1-butene-1,4-sultone, 3-butene-1,4-sultone, methyl fluorosulfonate, ethyl fluorosulfonate, methanesulfonic acid Sulfur-containing compounds such as methyl, ethyl methanesulfonate, busulfan, sulfolane, sulfolene, diphenylsulfone, N, N-dimethylmethanesulfonamide, N, N-diethylmethanesulfonamide; 1-methyl-2-pyrrolidinone, 1-methyl 2-piperidone, 3-methyl-2-oxazolidinone, 1,3-dimethyl-2-imidazolidino And nitrogen-containing compounds such as N-methylsuccinimide; acetonitrile, propionitrile, butyronitrile, isobutyronitrile, valeronitrile, isovaleronitrile, lauronitrile, 2-methylbutyronitrile, trimethylacetonitrile, hexanenitrile, cyclopentanecarbo Nitrile, cyclohexanecarbonitrile, acrylonitrile, methacrylonitrile, crotononitrile, 3-methylcrotononitrile, 2-methyl-2-butenenitryl, 2-pentenenitrile, 2-methyl-2-pentenenitrile, 3-methyl 2-pentenenitrile, 2-hexenenitrile, fluoroacetonitrile, difluoroacetonitrile, trifluoroacetonitrile, 2-fluoropropionitrile, 3-fluoropropionitrile, 2 , 2-difluoropropionitrile, 2,3-difluoropropionitrile, 3,3-difluoropropionitrile, 2,2,3-trifluoropropionitrile, 3,3,3-trifluoropropionitrile, 3, Cyano groups such as 3′-oxydipropionitrile, 3,3′-thiodipropionitrile, 1,2,3-propanetricarbonitrile, 1,3,5-pentanetricarbonitrile, pentafluoropropionitrile, etc. Compound having one; malononitrile, succinonitrile, glutaronitrile, adiponitrile, pimeonitrile, suberonitrile, azeronitrile, sebacononitrile, undecandinitrile, dodecandinitrile, methylmalononitrile, ethylmalononitrile, isopropylmalononitrile, tert-butylmalononitrile Methylsuccinonitrile, 2,2-dimethylsuccinonitrile, 2,3-dimethylsuccinonitrile, trimethylsuccinonitrile, tetramethylsuccinonitrile 3,3 ′-(ethylenedioxy) dipropionitrile, 3,3 Compounds having two cyano groups such as'-(ethylenedithio) dipropionitrile; 1,12-diisocyanatododecane, 1,11-diisocyanatoundecane, 1,10-diisocyanatodecane, 1,9- Compounds having two isocyanate groups such as diisocyanatononane, 1,8-diisocyanatooctane, 1,7-isocyanatoheptane, 1,6-diisocyanatohexane; heptane, octane, nonane, decane, cycloheptane Hydrocarbon compounds such as fluorobenzene, difluorobenzene, hexafluorobenze And fluorine-containing aromatic compounds such as benzotrifluoride. These may be used alone or in combination of two or more. By adding these auxiliaries, capacity maintenance characteristics and cycle characteristics after high temperature storage can be improved.

  The blending amount of other auxiliary agents is not particularly limited, and is arbitrary as long as the effects of the present invention are not significantly impaired. The other auxiliary agent is preferably 0.01% by mass or more and 5% by mass or less in 100% by mass of the non-aqueous solvent. Within this range, the effects of other auxiliaries can be sufficiently exhibited, and it is easy to avoid a situation in which battery characteristics such as high-load discharge characteristics deteriorate. The blending amount of other auxiliaries is more preferably 0.1% by mass or more, further preferably 0.2% by mass or more, more preferably 3% by mass or less, and further preferably 1% by mass or less. .

  The non-aqueous electrolyte solution described above includes those existing inside the non-aqueous electrolyte battery according to the present invention. Specifically, the components of the non-aqueous electrolyte solution such as lithium salt, solvent, and auxiliary agent are separately synthesized, and the non-aqueous electrolyte solution is prepared from what is substantially isolated by the method described below. In the case of a nonaqueous electrolyte solution in a nonaqueous electrolyte battery obtained by pouring into a separately assembled battery, the components of the nonaqueous electrolyte solution of the present invention are individually placed in the battery, In order to obtain the same composition as the non-aqueous electrolyte solution of the present invention by mixing in a non-aqueous electrolyte battery, the compound constituting the non-aqueous electrolyte solution of the present invention is further generated in the non-aqueous electrolyte battery. The case where the same composition as the aqueous electrolyte is obtained is also included.

2. Battery Configuration The non-aqueous electrolyte battery of the present invention is suitable for use as an electrolyte for a secondary battery, for example, a lithium secondary battery, among non-aqueous electrolyte batteries. Hereinafter, a non-aqueous electrolyte battery using the non-aqueous electrolyte of the present invention will be described.
The non-aqueous electrolyte secondary battery of the present invention can adopt a known structure. Typically, the negative electrode and the positive electrode capable of occluding and releasing ions (for example, lithium ions), and the non-aqueous electrolyte of the present invention described above. An aqueous electrolyte solution.

2-1. Negative electrode The negative electrode active material used for the negative electrode is described below. The negative electrode active material is not particularly limited as long as it can electrochemically occlude and release lithium ions. Specific examples include carbonaceous materials, alloy materials, lithium-containing metal composite oxide materials, and the like. These may be used individually by 1 type, and may be used together combining 2 or more types arbitrarily.

<Negative electrode active material>
Examples of the negative electrode active material include carbonaceous materials, alloy materials, lithium-containing metal composite oxide materials, and the like.
As a carbonaceous material used as a negative electrode active material,
(A) natural graphite,
(B) a carbonaceous material obtained by heat-treating an artificial carbonaceous material and an artificial graphite material at least once in the range of 400 to 3200 ° C;
(C) a carbonaceous material in which the negative electrode active material layer is made of carbonaceous materials having at least two or more different crystallinities and / or has an interface in contact with the different crystalline carbonaceous materials,
(D) a carbonaceous material in which the negative electrode active material layer is made of carbonaceous materials having at least two or more different orientations and / or has an interface in contact with the carbonaceous materials having different orientations;
Is preferably a good balance between initial irreversible capacity and high current density charge / discharge characteristics. Further, the carbonaceous materials (a) to (d) may be used alone or in combination of two or more in any combination and ratio.

Examples of the artificial carbonaceous material and the artificial graphite material of (b) include natural graphite, coal-based coke, petroleum-based coke, coal-based pitch, petroleum-based pitch, and those obtained by oxidizing these pitches, needle coke, pitch coke, and Carbon materials that are partially graphitized, furnace black, acetylene black, organic pyrolysis products such as pitch-based carbon fibers, carbonizable organic materials and their carbides, or carbonizable organic materials are benzene, toluene, xylene, quinoline And a solution dissolved in a low-molecular organic solvent such as n-hexane, and carbides thereof.

  As an alloy material used as the negative electrode active material, as long as lithium can be occluded / released, lithium alone, simple metals and alloys forming lithium alloys, or oxides, carbides, nitrides, silicides, sulfides thereof Any of compounds such as products or phosphides may be used and is not particularly limited. The single metal and alloy forming the lithium alloy are preferably materials containing group 13 and group 14 metal / metalloid elements (that is, excluding carbon), more preferably aluminum, silicon and tin (hereinafter referred to as “ Simple metals) and alloys or compounds containing these atoms (sometimes abbreviated as “specific metal elements”). These may be used individually by 1 type and may use 2 or more types together by arbitrary combinations and a ratio.

  As a negative electrode active material having at least one kind of atom selected from a specific metal element, a metal simple substance of any one specific metal element, an alloy composed of two or more specific metal elements, one type or two or more specific types Alloys comprising metal elements and one or more other metal elements, as well as compounds containing one or more specific metal elements, and oxides, carbides, nitrides and silicides of the compounds And composite compounds such as sulfides or phosphides. By using these simple metals, alloys or metal compounds as the negative electrode active material, the capacity of the battery can be increased.

  In addition, a compound in which these complex compounds are complexly bonded to several kinds of elements such as a simple metal, an alloy, or a nonmetallic element is also included. Specifically, for example, in silicon and tin, an alloy of these elements and a metal that does not operate as a negative electrode can be used. For example, in the case of tin, a complex compound containing 5 to 6 kinds of elements in combination with a metal that acts as a negative electrode other than tin and silicon, a metal that does not operate as a negative electrode, and a nonmetallic element may be used. it can.

  Among these negative electrode active materials, since the capacity per unit mass is large when a battery is formed, any one simple metal of a specific metal element, an alloy of two or more specific metal elements, oxidation of a specific metal element In particular, silicon and / or tin metal simple substance, alloy, oxide, carbide, nitride and the like are preferable from the viewpoint of capacity per unit mass and environmental load.

  The lithium-containing metal composite oxide material used as the negative electrode active material is not particularly limited as long as it can occlude and release lithium, but a material containing titanium and lithium is preferable from the viewpoint of high current density charge / discharge characteristics, A lithium-containing composite metal oxide material containing titanium is more preferable, and a composite oxide of lithium and titanium (hereinafter sometimes abbreviated as “lithium titanium composite oxide”). That is, it is particularly preferable to use a lithium titanium composite oxide having a spinel structure in a negative electrode active material for a non-aqueous electrolyte secondary battery because the output resistance is greatly reduced.

Further, lithium or titanium of the lithium titanium composite oxide is at least selected from the group consisting of other metal elements such as Na, K, Co, Al, Fe, Ti, Mg, Cr, Ga, Cu, Zn, and Nb. Those substituted with one element are also preferred.
The metal oxide is a lithium titanium composite oxide represented by the general formula (A). In the general formula (A), 0.7 ≦ x ≦ 1.5, 1.5 ≦ y ≦ 2.3, It is preferable that 0 ≦ z ≦ 1.6 because the structure upon doping and dedoping of lithium ions is stable.

_{Li x Ti y M z O 4} (A)
[In General Formula (1), M represents at least one element selected from the group consisting of Na, K, Co, Al, Fe, Ti, Mg, Cr, Ga, Cu, Zn, and Nb. ]
Among the compositions represented by the general formula (A),
(A) 1.2 ≦ x ≦ 1.4, 1.5 ≦ y ≦ 1.7, z = 0
(B) 0.9 ≦ x ≦ 1.1, 1.9 ≦ y ≦ 2.1, z = 0
(C) 0.7 ≦ x ≦ 0.9, 2.1 ≦ y ≦ 2.3, z = 0
This structure is particularly preferable because of a good balance of battery performance.

Particularly preferred representative compositions of the above compounds are Li _4/3 Ti _5/3 O ₄ in (a), Li ₁ Ti ₂ O ₄ in (b), Li _4/5 Ti _11/5 O in (c). ₄ . As for the structure of Z ≠ 0, for example, Li _4/3 Ti _4/3 Al _1/3 O ₄ is preferable.

<Physical properties of carbonaceous materials>
When using a carbonaceous material as a negative electrode active material, it is desirable to have the following physical properties.

(Rhombohedral crystal ratio)
The rhombohedral crystal ratio can be determined from the ratio of the rhombohedral structure graphite layer (ABC stacking layer) and the hexagonal structure graphite layer (AB stacking layer) by the X-ray wide angle diffraction method (XRD) using the following formula.
Rhombohedral crystal ratio (%) = integrated intensity of ABC (101) peak of XRD ÷
XRD AB (101) peak integrated intensity × 100
Here, the rhombohedral crystal ratio of the carbonaceous material that can be used in the present invention is usually 0% or more, preferably 3% or more, more preferably 5% or more, and particularly preferably 12% or more as a lower limit. is there. Moreover, as an upper limit, Preferably it is 35% or less, More preferably, it is 27% or less, More preferably, it is 24% or less, Most preferably, it is the range of 20% or less. Here, the rhombohedral crystal ratio of 0% indicates that no XRD peak derived from the ABC stacking layer is detected. On the other hand, “greater than 0%” means that even a slight XRD peak derived from the ABC stacking layer is detected.

  If the rhombohedral crystal ratio is within the above range, for example, there are few defects in the crystal structure of the carbonaceous material, the reactivity with the electrolytic solution is small, the consumption of the electrolytic solution during the cycle is small, and the cycle characteristics are excellent.

  The XRD measurement method for determining the rhombohedral crystal ratio is as follows: a 0.2 mm sample plate is filled so that the graphite powder is not oriented, and an X-ray diffractometer (for example, CuKα ray by X'Pert Pro MPD manufactured by PANalytical) is used. And an output of 45 kV and 40 mA). Using the obtained diffraction pattern, the peak integrated intensity is calculated by profile fitting using an asymmetric Pearson VII function using analysis software JADE 5.0, and the rhombohedral crystal ratio is obtained from the above formula.

The X-ray diffraction measurement conditions are as follows. “2θ” indicates a diffraction angle.
・ Target: Cu (Kα ray) graphite monochromator ・ Slit:
Solar slit 0.04 degree divergence slit 0.5 degree side divergence mask 15mm
Anti-scattering slit 1 degree ・ Measurement range and step angle / measurement time:
(101) plane: 41 ° ≦ 2θ ≦ 47.5 ° 0.3 ° / 60 seconds Background correction:
Connect 42.7 to 45.5 degrees with a straight line and subtract as background.
-Peak of rhombohedral-structure graphite particle layer: refers to a peak around 43.4 degrees.
-Peak of hexagonal structure graphite particle layer: It indicates a peak around 44.5 degrees.

  A method for obtaining graphite particles having a rhombohedral crystal ratio in the above range can employ a method of manufacturing using conventional techniques, and is not particularly limited, but the graphite particles are heat-treated at a temperature of 500 ° C. or higher. It is preferable to manufacture by this. In particular, mechanical effects such as compression, friction, shearing force, etc. including the interaction of particles are given to graphite particles mainly by impact force. In addition, the rhombohedral crystal ratio defined in the present invention can also be adjusted by changing the strength of mechanical action, processing time, presence / absence of repetition, and the like. Specifically, it has a rotor with a large number of blades installed inside the casing, and when the rotor rotates at high speed, mechanical action such as impact compression, friction, shearing force, etc. is applied to the carbon material introduced inside. An apparatus that provides a surface treatment is preferable. Moreover, it is preferable to have a mechanism that repeatedly gives a mechanical action by circulating a carbon material, or a mechanism that does not have a circulation mechanism but connects a plurality of apparatuses. As an example of a preferable apparatus, there can be mentioned a hybridization system manufactured by Nara Machinery Co., Ltd.

Further, it is more preferable to apply a heat treatment after applying the mechanical action.
Further, it is particularly preferable that after applying the mechanical action, it is combined with a carbon precursor and subjected to heat treatment at a temperature of 700 ° C. or higher.

(X-ray parameters)
The d value (interlayer distance) of the lattice plane (002 plane) obtained by X-ray diffraction by the Gakushin method of carbonaceous material is preferably 0.335 nm or more, and is usually 0.360 nm or less, 0 350 nm or less is preferable, and 0.345 nm or less is more preferable. Further, the crystallite size (Lc) of the carbonaceous material obtained by X-ray diffraction by the Gakushin method is preferably 1.0 nm or more, and more preferably 1.5 nm or more.

(Volume-based average particle size)
The volume-based average particle diameter of the carbonaceous material is a volume-based average particle diameter (median diameter) obtained by a laser diffraction / scattering method, and is usually 1 μm or more, preferably 3 μm or more, more preferably 5 μm or more, and 7 μm. The above is particularly preferable, and is usually 100 μm or less, preferably 50 μm or less, more preferably 40 μm or less, further preferably 30 μm or less, and particularly preferably 25 μm or less.

If the volume-based average particle size is below the above range, the irreversible capacity may increase, leading to loss of initial battery capacity. On the other hand, when the above range is exceeded, when an electrode is produced by coating, it tends to be a non-uniform coating surface, which may be undesirable in the battery manufacturing process.
The volume-based average particle size is measured by dispersing carbon powder in a 0.2% by weight aqueous solution (about 10 mL) of polyoxyethylene (20) sorbitan monolaurate, which is a surfactant, and laser diffraction / scattering particle size distribution. This is carried out using a meter (LA-700 manufactured by Horiba, Ltd.). The median diameter determined by the measurement is defined as the volume-based average particle diameter of the carbonaceous material of the present invention.

(Raman R value, Raman half width)
The Raman R value of the carbonaceous material is a value measured using an argon ion laser Raman spectrum method, and is usually 0.01 or more, preferably 0.03 or more, more preferably 0.1 or more, and usually 1.5 or less, preferably 1.2 or less, more preferably 1 or less, and particularly preferably 0.5 or less.

  When the Raman R value is below the above range, the crystallinity of the particle surface becomes too high, and there are cases where the number of sites where Li enters between layers decreases with charge / discharge. That is, charge acceptance may be reduced. In addition, when the negative electrode is densified by applying it to the current collector and then pressing it, the crystals are likely to be oriented in a direction parallel to the electrode plate, which may lead to a decrease in load characteristics. In particular, when a negative electrode active material having a Raman R value of 0.1 or more and a compound described in the general formula (1) are used in combination, the film forms a good network on the negative electrode surface and has a suitable film density. And cycle characteristics and load characteristics can be dramatically improved.

On the other hand, if it exceeds the above range, the crystallinity of the particle surface is lowered, the reactivity with the non-aqueous electrolyte is increased, and the efficiency may be lowered and the gas generation may be increased.
Further, the Raman half-width in the vicinity of 1580 cm ^{−1 of the} carbonaceous material is not particularly limited, but is usually 10 cm ⁻¹ or more, preferably 15 cm ⁻¹ or more, and usually 100 cm ⁻¹ or less, and 80 cm ⁻¹ or less. Preferably, it is more preferably 60 cm ⁻¹ or less, particularly preferably 40 cm ⁻¹ or less.

  If the Raman half width is less than the above range, the crystallinity of the particle surface becomes too high, and there are cases where the number of sites where Li enters between layers decreases with charge and discharge. That is, charge acceptance may be reduced. In addition, when the negative electrode is densified by applying it to the current collector and then pressing it, the crystals are likely to be oriented in a direction parallel to the electrode plate, which may lead to a decrease in load characteristics. On the other hand, if it exceeds the above range, the crystallinity of the particle surface is lowered, the reactivity with the non-aqueous electrolyte is increased, and the efficiency may be lowered and the gas generation may be increased.

The measurement of the Raman spectrum, using a Raman spectrometer (manufactured by JASCO Corporation Raman spectrometer), the sample is naturally dropped into the measurement cell and filled, and while irradiating the sample surface in the cell with argon ion laser light, This is done by rotating the cell in a plane perpendicular to the laser beam. The resulting Raman spectrum, the intensity I _A of the peak P _A in the vicinity of 1580 cm ^-1, and measuring the intensity I _B of a peak P _B in the vicinity of 1360 cm ^-1, the intensity ratio _{R (R = I B / I} A) Is calculated. The Raman R value calculated by the measurement is defined as the Raman R value of the carbonaceous material of the present invention. Further, the half width of the peak P _A in the vicinity of 1580 cm ^-1 of the resulting Raman spectrum was measured, which is defined as the Raman half-value width of the carbonaceous material of the present invention.

Moreover, said Raman measurement conditions are as follows.
Argon ion laser wavelength: 514.5nm
・ Laser power on the sample: 15-25mW
・ Resolution: 10-20cm ^-1
Measurement range: 1100 cm ^{−1 to} 1730 cm ⁻¹
・ Raman R value, Raman half width analysis: background processing,
-Smoothing processing: Simple average, 5 points of convolution

(Orientation ratio)
The orientation ratio of the carbonaceous material is usually 0.005 or more, preferably 0.01 or more, more preferably 0.015 or more, and usually 0.67 or less. When the orientation ratio is below the above range, the high-density charge / discharge characteristics may deteriorate. The upper limit of the above range is the theoretical upper limit value of the orientation ratio of the carbonaceous material.

The orientation ratio is measured by X-ray diffraction after pressure-molding the sample. Set the molded body obtained by filling 0.47 g of the sample into a molding machine with a diameter of 17 mm and compressing it with 58.8 MN · m ^{-2 so} that it is flush with the surface of the sample holder for measurement. X-ray diffraction is measured. From the (110) diffraction and (004) diffraction peak intensities of the obtained carbon, a ratio represented by (110) diffraction peak intensity / (004) diffraction peak intensity is calculated. The orientation ratio calculated by the measurement is defined as the orientation ratio of the carbonaceous material of the present invention.

The X-ray diffraction measurement conditions are as follows. “2θ” indicates a diffraction angle.
・ Target: Cu (Kα ray) graphite monochromator ・ Slit:
Divergence slit = 0.5 degree Light receiving slit = 0.15 mm
Scattering slit = 0.5 degree / measurement range and step angle / measurement time:
(110) plane: 75 degrees ≦ 2θ ≦ 80 degrees 1 degree / 60 seconds (004) plane: 52 degrees ≦ 2θ ≦ 57 degrees 1 degree / 60 seconds

(Aspect ratio (powder))
The aspect ratio of the carbonaceous material is usually 1 or more and usually 10 or less, preferably 8 or less, and more preferably 5 or less. If the aspect ratio exceeds the above range, streaking or a uniform coated surface cannot be obtained when forming an electrode plate, and the high current density charge / discharge characteristics may deteriorate. The lower limit of the above range is the theoretical lower limit value of the aspect ratio of the carbonaceous material.

  The aspect ratio is measured by magnifying and observing the carbonaceous material particles with a scanning electron microscope. Carbonaceous material particles when three-dimensional observation is performed by selecting arbitrary 50 graphite particles fixed to the end face of a metal having a thickness of 50 μm or less and rotating and tilting the stage on which the sample is fixed. The longest diameter a and the shortest diameter b orthogonal to it are measured, and the average value of a / b is obtained. The aspect ratio (a / b) obtained by the measurement is defined as the aspect ratio of the carbonaceous material of the present invention.

<Configuration and production method of negative electrode>
Any known method can be used for producing the electrode as long as the effects of the present invention are not significantly impaired. For example, it is formed by adding a binder, a solvent, and, if necessary, a thickener, a conductive material, a filler, etc. to a negative electrode active material to form a slurry, which is applied to a current collector, dried and then pressed. Can do.

  In the case of using an alloy-based material, a method of forming a thin film layer (negative electrode active material layer) containing the above-described negative electrode active material by a technique such as vapor deposition, sputtering, or plating is also used.

(Current collector)
As the current collector for holding the negative electrode active material, a known material can be arbitrarily used. Examples of the current collector for the negative electrode include metal materials such as aluminum, copper, nickel, stainless steel, and nickel-plated steel. Copper is particularly preferable from the viewpoint of ease of processing and cost.

  In addition, the shape of the current collector may be, for example, a metal foil, a metal cylinder, a metal coil, a metal plate, a metal thin film, an expanded metal, a punch metal, a foam metal, or the like when the current collector is a metal material. Among these, a metal thin film is preferable, a copper foil is more preferable, and a rolled copper foil by a rolling method and an electrolytic copper foil by an electrolytic method are more preferable.

  The thickness of the current collector is usually 1 μm or more, preferably 5 μm or more, and is usually 100 μm or less, preferably 50 μm or less. This is because if the thickness of the negative electrode current collector is too thick, the capacity of the entire battery may be too low, and conversely if it is too thin, handling may be difficult.

(Binder)
The binder for binding the negative electrode active material is not particularly limited as long as it is a material that is stable with respect to the non-aqueous electrolyte solution and the solvent used in manufacturing the electrode.
Specific examples include resin-based polymers such as polyethylene, polypropylene, polyethylene terephthalate, polymethyl methacrylate, aromatic polyamide, polyimide, cellulose, and nitrocellulose; SBR (styrene-butadiene rubber), isoprene rubber, butadiene rubber, fluorine rubber, Rubber polymers such as NBR (acrylonitrile / butadiene rubber) and ethylene / propylene rubber; styrene / butadiene / styrene block copolymer or hydrogenated product thereof; EPDM (ethylene / propylene / diene terpolymer), styrene / Thermoplastic elastomeric polymers such as ethylene / butadiene / styrene copolymers, styrene / isoprene / styrene block copolymers or hydrogenated products thereof; syndiotactic-1,2-polybutadiene, polyvinyl acetate , Soft resinous polymers such as ethylene / vinyl acetate copolymer, propylene / α-olefin copolymer; polyvinylidene fluoride, polytetrafluoroethylene, fluorinated polyvinylidene fluoride, polytetrafluoroethylene / ethylene copolymer, etc. And a polymer composition having ion conductivity of alkali metal ions (particularly lithium ions). These may be used individually by 1 type, or may use 2 or more types together by arbitrary combinations and ratios.

  The ratio of the binder to the negative electrode active material is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, particularly preferably 0.6% by mass or more, and preferably 20% by mass or less, 15% by mass. The following is more preferable, 10% by mass or less is further preferable, and 8% by mass or less is particularly preferable. When the ratio of the binder with respect to a negative electrode active material exceeds the said range, the binder ratio from which the amount of binders does not contribute to battery capacity may increase, and the fall of battery capacity may be caused. On the other hand, below the above range, the strength of the negative electrode may be reduced.

  In particular, when a rubbery polymer typified by SBR is contained as a main component, the ratio of the binder to the negative electrode active material is usually 0.1% by mass or more, preferably 0.5% by mass or more, and 0 .6% by mass or more is more preferable, and is usually 5% by mass or less, preferably 3% by mass or less, and more preferably 2% by mass or less. When the main component contains a fluorine-based polymer typified by polyvinylidene fluoride, the ratio to the negative electrode active material is usually 1% by mass or more, preferably 2% by mass or more, and more preferably 3% by mass or more. It is preferably 15% by mass or less, preferably 10% by mass or less, and more preferably 8% by mass or less.

(Thickener)
A thickener is normally used in order to adjust the viscosity of the slurry at the time of producing a negative electrode active material layer. The thickener is not particularly limited, and specific examples include carboxymethyl cellulose, methyl cellulose, hydroxymethyl cellulose, ethyl cellulose, polyvinyl alcohol, oxidized starch, phosphorylated starch, casein, and salts thereof. These may be used individually by 1 type, or may use 2 or more types together by arbitrary combinations and ratios.

  Further, when using a thickener, the ratio of the thickener to the negative electrode active material is usually 0.1% by mass or more, preferably 0.5% by mass or more, more preferably 0.6% by mass or more, Moreover, it is 5 mass% or less normally, 3 mass% or less is preferable, and 2 mass% or less is more preferable.

(Electrode density)
The electrode structure when the negative electrode active material is converted into an electrode is not particularly limited, but the density of the negative electrode active material present on the current collector is preferably 1 g · cm ⁻³ or more, and 1.2 g · cm ⁻³ or more. but more preferably, particularly preferably 1.3 g · cm ^-3 or more, preferably 2.2 g · cm ^-3 or less, more preferably 2.1 g · cm ^-3 or less, 2.0 g · cm ^-3 or less More preferably, 1.9
Particularly preferred is g · cm ⁻³ or less. When the density of the negative electrode active material existing on the current collector exceeds the above range, the negative electrode active material particles are destroyed, and the initial irreversible capacity increases or non-aqueous system near the current collector / negative electrode active material interface. There is a case where high current density charge / discharge characteristics are deteriorated due to decrease in permeability of the electrolytic solution. On the other hand, if the amount is less than the above range, the conductivity between the negative electrode active materials decreases, the battery resistance increases, and the capacity per unit volume may decrease.

(Thickness of negative electrode plate)
The thickness of the negative electrode plate is designed according to the positive electrode plate to be used, and is not particularly limited. However, the thickness of the negative electrode active material layer obtained by subtracting the thickness of the metal foil (current collector) from the negative electrode plate is usually 15 μm. Above, preferably 20 μm or more, more preferably 30 μm or more, and usually 300 μm or less, preferably 280 μm or less, more preferably 250 μm or less.

(Surface coating of negative electrode plate)
Moreover, you may use what adhered the substance of the composition different from this to the surface of the said negative electrode plate. Surface adhering substances include aluminum oxide, silicon oxide, titanium oxide, zirconium oxide, magnesium oxide, calcium oxide, boron oxide, antimony oxide, bismuth oxide, lithium sulfate, sodium sulfate, potassium sulfate, magnesium sulfate, calcium sulfate And sulfates such as aluminum sulfate and carbonates such as lithium carbonate, calcium carbonate and magnesium carbonate.

2-2. Positive electrode <positive electrode active material>
The positive electrode active material used for the positive electrode is described below.

(composition)
The positive electrode active material is not particularly limited as long as it can electrochemically occlude and release lithium ions. For example, a material containing lithium and at least one transition metal is preferable. Specific examples include lithium transition metal composite oxides and lithium-containing transition metal phosphate compounds.

The transition metal of the lithium transition metal composite oxide is preferably V, Ti, Cr, Mn, Fe, Co, Ni, Cu or the like, and specific examples include lithium-cobalt composite oxide such as LiCoO ₂ , LiMnO ₂ , LiMn. Examples thereof include lithium / manganese composite oxides such as ₂ O ₄ and Li ₂ MnO ₄ and lithium / nickel composite oxides such as LiNiO ₂ . Further, some of the transition metal atoms that are the main components of these lithium transition metal composite oxides are Al, Ti, V, Cr, Mn, Fe, Co, Li, Ni, Cu, Zn, Mg, Ga, Zr, and Si. Specific examples include lithium-nickel-cobalt-aluminum composite oxides, lithium-cobalt-nickel composite oxides, lithium-cobalt-manganese composite oxides, lithium- Nickel / manganese composite oxide, lithium / nickel / cobalt / manganese composite oxide, and the like can be given. Among these, lithium / nickel / manganese composite oxide and lithium / nickel / cobalt / manganese composite oxide are preferable because of good battery characteristics.

Specific examples of the substituted ones include, for example, Li _{1 + a} Ni _0.5 Mn _0.5 O ₂ , Li _{1 + a} Ni _0.8 Co _0.2 O ₂ , Li _{1 + a} Ni _0.85 Co _0.10 Al _0.05 O ₂ , Li _{1 + a} Ni _0.33 Co _0.33 Mn _0.33 O ₂ , Li _{1 + a} Ni _0.45 Mn _0.45 Co _0.1 O ₂ , Li _{1 + a} Ni _0.475 Mn _0.475 Co _0.05 O ₂ , Li _{1 + a} Mn _1.8 Al _0.2 O ₄ , Li _{1 + a} Mn ₂ O ₄ , Li _{1 + a} Mn _1.5 Ni _0.5 O ₄ , xLi ₂ MnO _3. (1-x) Li _{1 + a} MO ₂ (M = transition metal, for example from Li, Ni, Mn and Co A metal selected from the group consisting of (a; 0 <a ≦ 3.0). The ratio of these substituted metal elements in the composition formula is appropriately adjusted depending on the relationship between the battery characteristics of the battery using the element and the cost of the material.

The lithium-containing transition metal phosphate compound is Li _x MPO ₄ (M = a kind of element selected from the group consisting of Group 4 to Group 11 transition metals in the periodic table, x is 0 <x <1. 2), and the transition metal (M) is selected from the group consisting of V, Ti, Cr, Mg, Zn, Ca, Cd, Sr, Ba, Co, Ni, Fe, Mn, and Cu. It is preferably at least one element, and more preferably at least one element selected from the group consisting of Co, Ni, Fe, and Mn. For _{example, LiFePO 4, Li 3 Fe 2} (PO 4) 3, LiFeP 2 O 7 , etc. of phosphorus Santetsurui, cobalt phosphate such as LiCoPO _4, manganese phosphate such as LiMnPO _4, phosphoric acids such as LiNiPO ₄ Nickel, a part of transition metal atoms that are the main components of these lithium transition metal phosphate compounds are Al, Ti, V, Cr, Mn, Fe, Co, Li, Ni, Cu, Zn, Mg, Ga, Zr, Examples include those substituted with other metals such as Nb and Si.
Among these, iron phosphates such as LiFePO ₄ , Li ₃ Fe ₂ (PO ₄ ) ₃ , and LiFeP ₂ O ₇ are preferably used because they are less likely to cause metal elution at high temperatures and charged states and are inexpensive. It is done.

The above-mentioned “with Li _x MPO ₄ as the basic composition” means not only the composition represented by the composition formula but also a part of the site such as Fe in the crystal structure substituted with another element. Is also included. Furthermore, it means that not only a stoichiometric composition but also a non-stoichiometric composition in which some elements are deficient or the like is included. Other elements to be substituted are preferably elements such as Al, Ti, V, Cr, Mn, Fe, Co, Li, Ni, Cu, Zn, Mg, Ga, Zr, and Si. In the case of performing the substitution of other elements, the content is preferably 0.1 mol% or more and 5 mol% or less, more preferably 0.2 mol% or more and 2.5 mol% or less.

The said positive electrode active material may be used independently and may use 2 or more types together.
Further, foreign elements may be introduced into the lithium transition metal-based compound powder of the present invention. Different elements include B, Na, Mg, Al, K, Ca, Ti, V, Cr, Fe, Cu, Zn, Sr, Y, Zr, Nb, Ru, Rh, Pd, Ag, In, Sn, Sb. Te, Ba, Ta, Mo, W, Re, Os, Ir, Pt, Au, Pb, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu , Bi, N, F, Cl, Br, or I. These foreign elements may be incorporated into the crystal structure of the lithium transition metal compound, or may not be incorporated into the crystal structure of the lithium transition metal compound, and may be a single element or compound on the particle surface or grain boundary. May be unevenly distributed.

(Surface coating)
Moreover, you may use what the substance of the composition different from this adhered to the surface of the said positive electrode active material. Surface adhering substances include aluminum oxide, silicon oxide, titanium oxide, zirconium oxide, magnesium oxide, calcium oxide, boron oxide, antimony oxide, bismuth oxide, lithium sulfate, sodium sulfate, potassium sulfate, magnesium sulfate, calcium sulfate And sulfates such as aluminum sulfate, carbonates such as lithium carbonate, calcium carbonate, and magnesium carbonate, and carbon.

  For example, these surface adhering substances are dissolved or suspended in a solvent, impregnated and added to the positive electrode active material, and dried. After the surface adhering substance precursor is dissolved or suspended in a solvent and impregnated and added to the positive electrode active material, It can be made to adhere to the surface of the positive electrode active material by a method of reacting by heating or the like, a method of adding to the positive electrode active material precursor and firing simultaneously. In addition, when making carbon adhere, the method of making carbonaceous adhere mechanically later in the form of activated carbon etc. can also be used, for example.

The amount of the surface adhering substance is by mass with respect to the positive electrode active material, preferably 0.1 ppm or more, more preferably 1 ppm or more, still more preferably 10 ppm or more, and the upper limit, preferably 20% or less, more preferably, as the lower limit. Is used at 10% or less, more preferably 5% or less. The surface adhering substance can suppress the oxidation reaction of the electrolyte solution on the surface of the positive electrode active material and can improve the battery life. However, when the amount of the adhering quantity is too small, the effect is not sufficiently manifested. In the case where it is too high, the resistance may increase in order to inhibit the entry and exit of lithium ions, so this composition range is preferable.
In the present invention, a material in which a material having a different composition is attached to the surface of the positive electrode active material is also referred to as “positive electrode active material”.

(shape)
Examples of the shape of the positive electrode active material particles include a lump shape, a polyhedron shape, a sphere shape, an oval sphere shape, a plate shape, a needle shape, and a column shape, which are conventionally used. It is preferable that the secondary particles have a spherical shape or an elliptical shape. In general, an electrochemical element expands and contracts as the active material in the electrode expands and contracts as it is charged and discharged. Therefore, the active material is easily damaged due to the stress or the conductive path is broken. Therefore, it is preferable that the primary particles are aggregated to form secondary particles, rather than a single particle active material having only primary particles, in order to relieve expansion and contraction stress and prevent deterioration. In addition, spherical or oval spherical particles are less oriented during molding of the electrode than plate-like equiaxed particles, so that the expansion and contraction of the electrode during charging and discharging is small, and the electrode is produced. The mixing with the conductive material is also preferable because it is easy to mix uniformly.

(Median diameter d ₅₀ )
The median diameter d ₅₀ of the positive electrode active material particles (secondary particle diameter when primary particles aggregate to form secondary particles) is preferably 0.1 μm or more, more preferably 0.5 μm or more, The upper limit is preferably 20 μm or less, more preferably 18 μm or less, still more preferably 16 μm or less, and most preferably 15 μm or less. If the lower limit is not reached, a high tap density product may not be obtained. If the upper limit is exceeded, it takes time for the diffusion of lithium in the particles. When a conductive material, a binder, or the like is slurried with a solvent and applied as a thin film, problems such as streaking may occur. Here, by mixing two or more kinds of the positive electrode active materials having different median diameters d ₅₀ , the filling property at the time of forming the positive electrode can be further improved.

In the present invention, the median diameter d ₅₀ is measured by a known laser diffraction / scattering particle size distribution measuring apparatus. When LA-920 manufactured by HORIBA is used as a particle size distribution meter, a 0.1% by mass sodium hexametaphosphate aqueous solution is used as a dispersion medium for measurement, and a measurement refractive index of 1.24 is set after ultrasonic dispersion for 5 minutes. Measured.

(Average primary particle size)
When primary particles are aggregated to form secondary particles, the average primary particle diameter of the positive electrode active material is preferably 0.03 μm or more, more preferably 0.05 μm or more, and still more preferably 0.8. The upper limit is preferably 5 μm or less, more preferably 4 μm or less, still more preferably 3 μm or less, and most preferably 2 μm or less. If the above upper limit is exceeded, it is difficult to form spherical secondary particles, which adversely affects the powder filling property, or the specific surface area is greatly reduced, so that there is a high possibility that battery performance such as output characteristics will deteriorate. is there. On the other hand, when the value falls below the lower limit, there is a case where problems such as inferior reversibility of charge / discharge are usually caused because crystals are not developed.

In the present invention, the primary particle diameter is measured by observation using a scanning electron microscope (SEM). Specifically, in a photograph at a magnification of 10000 times, the longest value of the intercept by the left and right boundary lines of the primary particles with respect to the horizontal straight line is obtained for any 50 primary particles and obtained by taking the average value. It is done.

<Configuration and manufacturing method of positive electrode>
The structure of the positive electrode will be described below. In the present invention, the positive electrode can be produced by forming a positive electrode active material layer containing a positive electrode active material and a binder on a current collector. Manufacture of the positive electrode using a positive electrode active material can be performed by a conventional method. That is, a positive electrode active material and a binder, and if necessary, a conductive material and a thickener mixed in a dry form into a sheet form are pressure-bonded to the positive electrode current collector, or these materials are used as a liquid medium. A positive electrode can be obtained by forming a positive electrode active material layer on the current collector by applying it to a positive electrode current collector and drying it as a slurry by dissolving or dispersing in a slurry.

  The content of the positive electrode active material in the positive electrode active material layer is preferably 80% by mass or more, more preferably 82% by mass or more, and particularly preferably 84% by mass or more. Moreover, an upper limit becomes like this. Preferably it is 95 mass% or less, More preferably, it is 93 mass% or less. If the content of the positive electrode active material in the positive electrode active material layer is low, the electric capacity may be insufficient. Conversely, if the content is too high, the strength of the positive electrode may be insufficient.

The positive electrode active material layer obtained by coating and drying is preferably consolidated by a hand press, a roller press or the like in order to increase the packing density of the positive electrode active material. The density of the positive electrode active material layer is preferably 1.5 g / cm ³ or more as a lower limit, more preferably 2 g / cm ³ , further preferably 2.2 g / cm ³ or more, and preferably 4.0 g as an upper limit. / cm ³ or less, more preferably 3.8 g / cm ³ or less, more preferably 3.6 g / cm ³ or less. If it exceeds this range, the permeability of the electrolyte solution to the vicinity of the current collector / active material interface decreases, and the charge / discharge characteristics particularly at a high current density decrease, and a high output may not be obtained. On the other hand, if it is lower, the conductivity between the active materials is lowered, the battery resistance is increased, and a high output may not be obtained.

(Conductive material)
A known conductive material can be arbitrarily used as the conductive material. Specific examples include metal materials such as copper and nickel; graphite such as natural graphite and artificial graphite (graphite); carbon black such as acetylene black; and carbon materials such as amorphous carbon such as needle coke. In addition, these may be used individually by 1 type and may use 2 or more types together by arbitrary combinations and a ratio. The conductive material is usually 0.01% by mass or more, preferably 0.1% by mass or more, more preferably 1% by mass or more in the positive electrode active material layer, and the upper limit is usually 50% by mass or less, preferably It is used so as to contain 30% by mass or less, more preferably 15% by mass or less. If the content is lower than this range, the conductivity may be insufficient. Conversely, if the content is higher than this range, the battery capacity may decrease.

(Binder)
The binder used for manufacturing the positive electrode active material layer is not particularly limited, and in the case of a coating method, any material that can be dissolved or dispersed in a liquid medium used during electrode manufacturing may be used. Resin polymers such as polyethylene, polypropylene, polyethylene terephthalate, polymethyl methacrylate, polyimide, aromatic polyamide, cellulose, nitrocellulose; SBR (styrene-butadiene rubber), NBR (acrylonitrile-butadiene rubber), fluorine rubber, isoprene rubber , Rubber polymers such as butadiene rubber and ethylene-propylene rubber; styrene / butadiene / styrene block copolymer or hydrogenated product thereof, EPDM (ethylene / propylene / diene terpolymer), styrene / ethylene / butadiene / Ethylene copolymer, styrene Thermoplastic elastomeric polymer such as isoprene / styrene block copolymer or hydrogenated product thereof; syndiotactic-1,2-polybutadiene, polyvinyl acetate, ethylene / vinyl acetate copolymer, propylene / α-olefin copolymer Soft resinous polymers such as polymers; Fluoropolymers such as polyvinylidene fluoride (PVdF), polytetrafluoroethylene, fluorinated polyvinylidene fluoride, polytetrafluoroethylene / ethylene copolymers; alkali metal ions (especially lithium ions) And a polymer composition having ion conductivity. In addition, these substances may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and a ratio.

[Manufacture of electrolyte]
Examples 2 to 14 using LiPF ₆ , monofluoroethylene carbonate, dimethyl carbonate, a compound represented by the general formula (1) and other compounds so as to have the ratio of Table 4 in a dry argon atmosphere, and The electrolyte solution used for Comparative Examples 3-6 was prepared. The concentration of LiPF ₆ was adjusted to 1 mol / L with respect to the solvent composition obtained by adding monofluoroethylene carbonate and dimethyl carbonate.

(Thickener)
A thickener can be used normally in order to adjust the viscosity of the slurry used for manufacture of a positive electrode active material layer. In particular, when an aqueous medium is used, it is preferable to make a slurry using a thickener and a latex such as styrene-butadiene rubber (SBR). The thickener is not particularly limited, and specific examples include carboxymethyl cellulose, methyl cellulose, hydroxymethyl cellulose, ethyl cellulose, polyvinyl alcohol, oxidized starch, phosphorylated starch, casein, and salts thereof. These may be used individually by 1 type, or may use 2 or more types together by arbitrary combinations and ratios. When a thickener is further added, the ratio of the thickener to the active material is 0.1% by mass or more, preferably 0.5% by mass or more, more preferably 0.6% by mass or more. The upper limit is 5% by mass or less, preferably 3% by mass or less, more preferably 2% by mass or less. Below this range, applicability may be significantly reduced. If it exceeds, the ratio of the active material in the positive electrode active material layer may decrease, and there may be a problem that the capacity of the battery decreases and a problem that the resistance between the positive electrode active materials increases.

(Current collector)
The material of the positive electrode current collector is not particularly limited, and a known material can be arbitrarily used. Specific examples include metal materials such as aluminum, stainless steel, nickel plating, titanium, and tantalum; and carbon materials such as carbon cloth and carbon paper. Of these, metal materials, particularly aluminum, are preferred.

  Examples of the shape of the current collector include metal foil, metal cylinder, metal coil, metal plate, metal thin film, expanded metal, punch metal, and foam metal in the case of a metal material. A thin film, a carbon cylinder, etc. are mentioned. Of these, metal thin films are preferred. In addition, you may form a thin film suitably in mesh shape. Although the thickness of the thin film is arbitrary, it is usually 1 μm or more, preferably 3 μm or more, more preferably 5 μm or more, and the upper limit is usually 1 mm or less, preferably 100 μm or less, more preferably 50 μm or less. If the thin film is thinner than this range, the strength required for the current collector may be insufficient. Conversely, if the thin film is thicker than this range, the handleability may be impaired.

  Moreover, it is also preferable from the viewpoint of reducing the electronic contact resistance between the current collector and the positive electrode active material layer that a conductive additive is applied to the surface of the current collector. Examples of the conductive assistant include noble metals such as carbon, gold, platinum, and silver.

(Thickness of positive plate)
The thickness of the positive electrode plate is not particularly limited, but from the viewpoint of high capacity and high output, the thickness of the positive electrode active material layer obtained by subtracting the thickness of the metal foil (current collector) from the positive electrode plate is set on one side of the current collector. As a lower limit,
The upper limit is preferably 10 μm or more, more preferably 20 μm or more, and the upper limit is preferably 500 μm or less, more preferably 450 μm or less.

(Positive electrode surface coating)
Moreover, you may use what adhered the substance of the composition different from this to the surface of the said positive electrode plate. Surface adhering substances include aluminum oxide, silicon oxide, titanium oxide, zirconium oxide, magnesium oxide, calcium oxide, boron oxide, antimony oxide, bismuth oxide, lithium sulfate, sodium sulfate, potassium sulfate, magnesium sulfate, calcium sulfate And sulfates such as aluminum sulfate, carbonates such as lithium carbonate, calcium carbonate, and magnesium carbonate, and carbon.

2-3. Separator Normally, a separator is interposed between the positive electrode and the negative electrode in order to prevent a short circuit. In this case, the nonaqueous electrolytic solution of the present invention is usually used by impregnating the separator.
The material and shape of the separator are not particularly limited, and known ones can be arbitrarily adopted as long as the effects of the present invention are not significantly impaired. Among them, a resin, glass fiber, inorganic material, etc. formed of a material that is stable with respect to the non-aqueous electrolyte solution of the present invention is used, and a porous sheet or a nonwoven fabric-like material having excellent liquid retention properties is used. Is preferred.

  As materials for the resin and glass fiber separator, for example, polyolefins such as polyethylene and polypropylene, aromatic polyamides, polytetrafluoroethylene, polyethersulfone, glass filters and the like can be used. Of these, glass filters and polyolefins are preferred, and polyolefins are more preferred. These materials may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and a ratio.

  The thickness of the separator is arbitrary, but is usually 1 μm or more, preferably 5 μm or more, more preferably 10 μm or more, and usually 50 μm or less, preferably 40 μm or less, more preferably 30 μm or less. If the separator is too thin than the above range, the insulating properties and mechanical strength may decrease. On the other hand, if it is thicker than the above range, not only the battery performance such as the rate characteristic may be lowered, but also the energy density of the whole non-aqueous electrolyte secondary battery may be lowered.

  Furthermore, when using a porous material such as a porous sheet or nonwoven fabric as the separator, the porosity of the separator is arbitrary, but is usually 20% or more, preferably 35% or more, more preferably 45% or more, Further, it is usually 90% or less, preferably 85% or less, and more preferably 75% or less. If the porosity is too smaller than the above range, the membrane resistance tends to increase and the rate characteristics tend to deteriorate. Moreover, when larger than the said range, it exists in the tendency for the mechanical strength of a separator to fall and for insulation to fall.

  Moreover, although the average pore diameter of a separator is also arbitrary, it is 0.5 micrometer or less normally, 0.2 micrometer or less is preferable, and it is 0.05 micrometer or more normally. If the average pore diameter exceeds the above range, a short circuit tends to occur. On the other hand, below the above range, the film resistance may increase and the rate characteristics may deteriorate.

  On the other hand, as inorganic materials, for example, oxides such as alumina and silicon dioxide, nitrides such as aluminum nitride and silicon nitride, and sulfates such as barium sulfate and calcium sulfate are used. Used.

As the form, a thin film shape such as a non-woven fabric, a woven fabric, or a microporous film is used. In the thin film shape, those having a pore diameter of 0.01 to 1 μm and a thickness of 5 to 50 μm are preferably used.
In addition to the above-mentioned independent thin film shape, a separator formed by forming a composite porous layer containing inorganic particles on the surface layer of the positive electrode and / or the negative electrode using a resin binder can be used. For example, a porous layer may be formed by using alumina particles having a 90% particle size of less than 1 μm on both surfaces of the positive electrode and using a fluororesin as a binder.

  The characteristics of the separator in the non-electrolyte secondary battery can be grasped by the Gurley value. The Gurley value indicates the difficulty of air passage in the film thickness direction, and is expressed as the number of seconds required for 100 ml of air to pass through the film. It means that it is harder to go through. That is, a smaller value means better communication in the thickness direction of the film, and a larger value means lower communication in the thickness direction of the film. Communication is the degree of connection of holes in the film thickness direction. If the Gurley value of the separator of the present invention is low, it can be used for various purposes. For example, when used as a separator for a non-aqueous lithium secondary battery, a low Gurley value means that lithium ions can be easily transferred and is preferable because of excellent battery performance. Although the Gurley value of a separator is arbitrary, Preferably it is 10-1000 second / 100ml, More preferably, it is 15-800 second / 100ml, More preferably, it is 20-500 second / 100ml. If the Gurley value is 1000 seconds / 100 ml or less, the electrical resistance is substantially low, which is preferable as a separator.

2-4. Battery design <electrode group>
The electrode group has a laminated structure in which the positive electrode plate and the negative electrode plate are interposed through the separator, and a structure in which the positive electrode plate and the negative electrode plate are wound in a spiral shape through the separator. Either is acceptable. The ratio of the volume of the electrode group to the internal volume of the battery (hereinafter referred to as the electrode group occupation ratio) is usually 40% or more, preferably 50% or more, and usually 90% or less, preferably 80% or less. .

  When the electrode group occupancy is below the above range, the battery capacity decreases. Also, if the above range is exceeded, the void space is small, the battery expands, and the member expands or the vapor pressure of the electrolyte liquid component increases and the internal pressure rises. In some cases, the gas release valve that lowers various characteristics such as storage at high temperature and the like, or releases the internal pressure to the outside is activated.

<Exterior case>
The material of the outer case is not particularly limited as long as it is a substance that is stable with respect to the non-aqueous electrolyte used. Specifically, a nickel-plated steel plate, stainless steel, aluminum, an aluminum alloy, a metal such as a magnesium alloy, or a laminated film (laminate film) of a resin and an aluminum foil is used. From the viewpoint of weight reduction, an aluminum or aluminum alloy metal or a laminate film is preferably used.

  In an exterior case using metals, the metal is welded together by laser welding, resistance welding, or ultrasonic welding to form a sealed sealed structure, or a caulking structure using the above metals via a resin gasket. Things. Examples of the outer case using the laminate film include a case where a resin-sealed structure is formed by heat-sealing resin layers. In order to improve sealing performance, a resin different from the resin used for the laminate film may be interposed between the resin layers. In particular, when a resin layer is heat-sealed through a current collecting terminal to form a sealed structure, a metal and a resin are joined, so that a resin having a polar group or a modified group having a polar group introduced as an intervening resin is used. Resins are preferably used.

<Protective element>
Protection elements such as PTC (Positive Temperature Coefficient), thermal fuse, thermistor, which increases resistance when abnormal heat is generated or excessive current flows, shuts off current flowing through the circuit due to sudden increase in battery internal pressure or internal temperature during abnormal heat generation A valve (current cutoff valve) or the like can be used. It is preferable to select a protective element that does not operate under normal use at a high current, and it is more preferable that the protective element is designed so as not to cause abnormal heat generation or thermal runaway even without the protective element.

<Exterior body>
The non-aqueous electrolyte secondary battery of the present invention is usually configured by housing the non-aqueous electrolyte, the negative electrode, the positive electrode, the separator, and the like in an exterior body. This exterior body is not particularly limited, and any known one can be arbitrarily adopted as long as the effects of the present invention are not significantly impaired. Specifically, the material of the exterior body is arbitrary, but usually, for example, nickel-plated iron, stainless steel, aluminum or an alloy thereof, nickel, titanium, or the like is used.
The shape of the exterior body is also arbitrary, and may be any of a cylindrical shape, a square shape, a laminate shape, a coin shape, a large size, and the like.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to these examples.

<Synthesis of Compound Represented by General Formula (1)>
The compound represented by the general formula (1) used in this example was synthesized by the following method.

[Synthesis of Compound I]
The raw material 1) was synthesized according to the method of non-patent literature (Journal of Organic Chemistry, 56 (3), 1083-1088 (1991)). Next, using raw material 1), Compound I was obtained by a method according to non-patent literature (European journal of organic chemistry, 2009 (20), 2836-2844).

[Synthesis of Compound II]
Under a nitrogen stream, the raw material 1) was dissolved in methylene chloride, and the methylene chloride solution of the raw material 3) was added dropwise. After stirring at room temperature for 3 hours, the reaction was stopped by adding water, and the organic layer was washed with saturated aqueous sodium bicarbonate and water, dried over magnesium sulfate, and then the solvent was removed under reduced pressure to obtain Intermediate 1). This intermediate 1) was dissolved in acetonitrile, and an aqueous solution in which a catalytic amount of ruthenium chloride was dissolved and sodium periodate were sequentially added while stirring on ice, and stirred for 1 hour. Diethyl ether and saturated aqueous sodium hydrogen carbonate were added, and the mixture was extracted into an organic layer. After drying with sodium sulfate, the residue was purified by silica gel column chromatography to obtain Compound II.

[Synthesis of Compound III]
Under a nitrogen stream, the tetrahydrofuran raw material 1) was dissolved, triethylamine was added to make it basic, and then a tetrahydrofuran solution of the raw material 4) was added dropwise. Thereafter, the mixture was stirred at room temperature for 2 hours, and the precipitated white powder was filtered off, and then the solvent was removed under reduced pressure to obtain Compound III.

  The spectral data of compounds I to III are shown below.

<Example A>
[Production of negative electrode]
98 parts by mass of a carbonaceous material, 100 parts by mass of an aqueous dispersion of sodium carboxymethylcellulose (concentration of 1% by mass of carboxymethylcellulose sodium) and an aqueous dispersion of styrene-butadiene rubber (styrene-butadiene, respectively) as a thickener and a binder 1 part by mass of rubber concentration 50 mass%) was added and mixed with a disperser to form a slurry. The obtained slurry was applied to a copper foil having a thickness of 10 μm, dried, and rolled with a press. The active material layer was 30 mm wide, 40 mm long, 5 mm wide, and 9 mm long uncoated. It cut out into the shape which has a part, and it was set as the negative electrode used for Examples 1-22, Comparative Examples 1-14, and Reference Example 1, respectively.

[Production of positive electrode]
90% by mass of LiCoO ₂ as a positive electrode active material, 5% by mass of acetylene black as a conductive material, and 5% by mass of polyvinylidene fluoride (PVdF) as a binder were mixed in an N-methylpyrrolidone solvent. And slurried. The obtained slurry was applied to an aluminum foil having a thickness of 15 μm, dried, and rolled with a press. The active material layer was 30 mm in width, 40 mm in length, 5 mm in width, and 9 mm in length. It cut out into the shape which has a process part, and was set as the positive electrode.

[Manufacture of electrolyte]
In the dry argon atmosphere, LiPF ₆ , monofluoroethylene carbonate (MFEC), ethylene carbonate (EC), dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), and general formula (1) as shown in Table 2 The electrolyte solution used for Example 1 and Comparative Examples 1 and 2 was prepared using the compound represented except the compound represented by General formula (1). The concentration of LiPF ₆ was adjusted to 1.4 mol / L with respect to the total solvent composition of MFEC, EC, DMC, and EMC.

[Manufacture of lithium secondary batteries]
The positive electrode, the negative electrode, and the polyethylene separator were laminated in the order of the negative electrode, the separator, and the positive electrode to prepare a battery element. The battery element was inserted into a bag made of a laminate film in which both surfaces of aluminum (thickness: 40 μm) were covered with a resin layer while projecting positive and negative terminals, and each electrolyte solution shown in Table 2 was then placed in the bag. The sheet-like battery was manufactured and used as Example 1 and Comparative Examples 1 and 2, respectively.

[Evaluation of initial discharge capacity]
The lithium secondary battery was conditioned with a constant current corresponding to 0.2 C at 25 ° C. in a state of being sandwiched between glass plates in order to improve the adhesion between the electrodes. The battery that had been conditioned was charged with a constant current corresponding to 0.2 C at 25 ° C., and then discharged with a constant current corresponding to 0.2 C to obtain an initial discharge capacity. The results are shown in Table 3. Here, 1C represents a current value for discharging the reference capacity of the battery in one hour, and 0.2C represents a current value of 1/5 thereof.

[Evaluation of high-temperature storage characteristics]
The battery for which the initial capacity evaluation test was completed was immersed in an ethanol bath and the volume was measured. After charging at a constant current of 0.2 C, the battery was charged at a constant voltage until the current value reached 0.05 C. This was stored at 85 ° C. for 24 hours, and after cooling the battery, the volume was measured by immersion in an ethanol bath, and the amount of gas generated from the volume change before and after continuous charging was determined. Then, after discharging at 25 ° C. with a constant current of 0.2 C to determine the remaining capacity, charging with a constant current of 0.2 C and then charging with a constant voltage until the current value becomes 0.05 C, a constant current of 1 C is obtained. Discharging with current was performed to determine 1C discharge capacity. The results are shown in Table 3.

  As is apparent from Table 3, the battery using the non-aqueous electrolyte solution according to the present invention (Example 1) is compared with the battery using the non-aqueous electrolyte solution according to the present invention (Comparative Examples 1 and 2). Thus, the amount of gas generated after high temperature storage can be greatly reduced.

<Example B>
[Production of positive electrode]
A slurry is prepared by mixing 90% by mass of LiCoO ₂ as a positive electrode active material, 5% by mass of acetylene black as a conductive material, and 5% by mass of polyvinylidene fluoride as a binder in an N-methylpyrrolidone solvent. did. The obtained slurry was applied to an aluminum foil having a thickness of 15 μm, dried, and rolled with a press. The active material layer was 30 mm in width, 40 mm in length, 5 mm in width, and 9 mm in length. It cut out into the shape which has a process part, and it was set as the positive electrode used for Examples 2-14 and Comparative Examples 3-6.

[Manufacture of electrolyte]
Examples 2 to 14, using LiPF ₆ , monofluoroethylene carbonate, dimethyl carbonate, the compound represented by the general formula (1) and other compounds so as to have the ratio of Table 4 in a dry argon atmosphere, and The electrolyte solution used for Comparative Examples 3-6 was prepared. The concentration of LiPF ₆ was adjusted to 1 mol / L with respect to the solvent composition obtained by adding monofluoroethylene carbonate and dimethyl carbonate.

[Manufacture of lithium secondary batteries]
A sheet-like battery was produced in the same manner as in Example <A> except that the positive electrode and the electrolytic solution were used.

[Evaluation of initial discharge capacity]
In a state where the lithium secondary battery is sandwiched between glass plates in order to improve the adhesion between the electrodes,
The running-in operation was performed at a constant current corresponding to 0.2C. The battery that had been conditioned was charged with a constant current corresponding to 0.2 C at 25 ° C., and then discharged with a constant current corresponding to 0.2 C to obtain an initial discharge capacity.

[Evaluation of cycle characteristics]
The lithium secondary battery for which the initial discharge capacity was evaluated was charged at a constant current of 0.5 C at 45 ° C. and then discharged at a constant current of 0.5 C, and 100 cycles were performed. The discharge capacity retention rate was determined from the formula of (discharge capacity at the 100th cycle) ÷ (discharge capacity at the first cycle) × 100.

[Evaluation of high-temperature storage characteristics]
A lithium secondary battery whose initial discharge capacity has been evaluated is charged with a constant current-constant voltage (0.05 C cut) at 25 ° C. at 25 ° C. and then stored at 85 ° C. for 24 hours to cool the battery to room temperature. Then, the volume was measured by immersing in an ethanol bath, and the amount of gas generated from the volume change before and after high-temperature storage was determined.

  As is apparent from Table 4, the batteries using the non-aqueous electrolyte solution according to the present invention (Examples 2 to 14) are batteries using the non-aqueous electrolyte solution not containing the compound represented by the general formula (1). Compared with (Comparative Examples 3 to 6), the cycle capacity retention rate is excellent. Further, even when the battery voltage is higher than that in <Example A>, the effect of the present invention is remarkably shown. Furthermore, even if it is a case where auxiliary agents, such as a cyclic carbonate which has an unsaturated bond, are contained (Examples 2-9), the effect of this invention can be confirmed similarly. This is because, when a compound represented by the general formula (1) is introduced together with a carbonate having a fluorine atom, the carbonate having a fluorine atom is taken into the electrode protective layer formed by the compound represented by the general formula (1). It is presumed that the electrode surface durability is remarkably improved by highly cross-linking, and as a result, the above-mentioned remarkable battery durability performance is improved.

<Example C>
[Production of positive electrode]
90% by mass of Li (Ni _1/3 Mn _1/3 Co _1/3 ) O ₂ as a positive electrode active material, 5% by mass of acetylene black as a conductive material, 5% by mass of polyvinylidene fluoride as a binder, Were slurried by mixing in N-methylpyrrolidone solvent. The obtained slurry was applied to a 15 μm-thick aluminum foil previously coated with a conductive additive, dried, and rolled with a press machine. The active material layer size was 30 mm wide, 40 mm long, and 5 mm wide. The positive electrode used in Example 15, Comparative Examples 7 and 8, and Reference Example 1 was cut into a shape having an uncoated part with a length of 9 mm.

[Manufacture of electrolyte]
Under a dry argon atmosphere, a basic electrolyte solution was prepared by dissolving LiPF ₆ dried in a mixture of ethylene carbonate, dimethyl carbonate and diethyl carbonate (volume ratio 30:30:40) to a ratio of 1 mol / L. The basic electrolyte solution was mixed with a carbonate having a fluorine atom and / or a compound represented by the general formula (1) at a ratio shown in Table 5, and Example 15, Comparative Examples 7, 8, and Reference Example 1 were mixed. It was set as the electrolyte solution to be used.

[Manufacture of lithium secondary batteries]
A sheet battery was prepared in the same manner as in Example <A> except that the positive electrode and the basic electrolyte were used.

[Evaluation of cycle characteristics]
After confirming the capacity with a constant current corresponding to 0.2 C at 25 ° C. in a state where the lithium secondary battery is sandwiched between glass plates in order to improve the adhesion between the electrodes, a constant current of 2 C at 60 ° C. After charging, the process of discharging at a constant current of 2C was taken as one cycle, and 300 cycles were performed. The discharge capacity retention ratio was calculated from the formula of (discharge capacity at 300th cycle) ÷ (discharge capacity at the first cycle) × 100.

As is clear from Table 5, the battery using the non-aqueous electrolyte solution according to the present invention (Example 15) is a battery using the non-aqueous electrolyte solution not containing the compound represented by the general formula (1) (Comparison). Compared to Examples 7 and 8), the cycle capacity retention rate is excellent. Further, even when the battery voltage is higher than in Examples <A> and <B>, the cycle capacity retention rate is excellent. In addition, the compound represented by the general formula (1) alone has a function of protecting the electrode surface and improving the battery durability (Reference Example 1). Durability is improved.
The reason for this is that when a carbonate having a fluorine atom and a compound represented by the general formula (1) are used in combination, the carbonate having a fluorine atom is taken into the electrode protective layer formed by the compound represented by the general formula (1). Therefore, it is presumed that the electrode surface durability is remarkably improved by highly crosslinking, and as a result, the above-mentioned remarkable battery durability performance is improved.

<Example D>
[Production of positive electrode]
90% by mass of Li (Ni _1/3 Mn _1/3 Co _1/3 ) O ₂ as a positive electrode active material, 5% by mass of acetylene black as a conductive material, 5% by mass of polyvinylidene fluoride as a binder, Were slurried by mixing in N-methylpyrrolidone solvent. The obtained slurry was applied to a 15 μm-thick aluminum foil previously coated with a conductive additive, dried, and rolled with a press machine. The active material layer size was 30 mm wide, 40 mm long, and 5 mm wide. The positive electrode used in Examples 16 to 18 and Comparative Examples 9 and 10 was cut into a shape having an uncoated part with a length of 9 mm.

[Manufacture of electrolyte]
In a dry argon atmosphere, the basic electrolyte solution was prepared by dissolving LiPF ₆ in a mixture of monofluoroethylene carbonate, dimethyl carbonate, and ethyl methyl carbonate (volume ratio 30:30:40) to a ratio of 1 mol / L. Prepared. The basic electrolyte solution is mixed with the compound represented by the general formula (1) or other compounds at the ratio shown in Table 6, and the electrolyte solution used in Examples 16 to 18 and Comparative Examples 9 and 10 did.

[Manufacture of lithium secondary batteries]
A sheet-like battery was produced in the same manner as in Example <A> except that the positive electrode and the electrolytic solution were used.

[Evaluation of cycle characteristics]
After confirming the capacity with a constant current corresponding to 0.2 C at 25 ° C. in a state where the lithium secondary battery is sandwiched between glass plates in order to improve the adhesion between the electrodes, a constant current of 2 C at 60 ° C. After charging, the process of discharging at a constant current of 2C was taken as one cycle, and 300 cycles were performed. The discharge capacity retention ratio was calculated from the formula of (discharge capacity at 300th cycle) ÷ (discharge capacity at the first cycle) × 100.

As is clear from Table 6, the batteries (Examples 16 to 18) using the non-aqueous electrolyte according to the present invention are batteries using a non-aqueous electrolyte that does not contain the compound represented by the general formula (1). Compared to a battery (Comparative Example 9) using a non-aqueous electrolyte containing a similar compound not included in the range represented by (Comparative Example 10) or the general formula (1), the cycle capacity retention rate is excellent. Thus, as long as it is a compound contained in the range represented by General formula (1), it turns out that it is excellent in a cycle capacity | capacitance maintenance factor, no matter what compound is used.
On the other hand, even in the case of a compound having a multiple bond site outside the ring as in the compound represented by the general formula (1), when a compound having a carbon-carbon double bond outside the ring is used (comparison) Even when Example 9) and a carbonate having a fluorine atom are used in combination, the durability improvement effect is greatly inferior to Examples 16-18.
The reason for this is that when a carbonate having a fluorine atom and a compound represented by the general formula (1) are used in combination, the carbonate having a fluorine atom is taken into the electrode protective layer formed by the compound represented by the general formula (1). Therefore, it is presumed that the electrode surface durability is remarkably improved by highly crosslinking, and as a result, the above-mentioned remarkable battery durability performance is improved.

<Example E>
[Production of positive electrode]
85% by mass of Li _1.1 (Ni _0.45 Mn _0.45 Co _0.10 ) O ₂ as a positive electrode active material, 10% by mass of acetylene black as a conductive material, and 5% by mass of polyvinylidene fluoride as a binder, N-methyl Mix in a pyrrolidone solvent to make a slurry. The obtained slurry was applied to a 15 μm-thick aluminum foil previously coated with a conductive additive, dried, and rolled with a press machine. The active material layer size was 30 mm wide, 40 mm long, and 5 mm wide. The positive electrode used in Examples 19 and 20 and Comparative Examples 11 to 13 was cut into a shape having an uncoated portion with a length of 9 mm.

[Manufacture of electrolyte]
LiPF ₆ dried in a mixture (volume ratio 30:30:40) of monofluoroethylene carbonate, dimethyl carbonate, and ethyl methyl carbonate in a dry argon atmosphere
Was dissolved at a rate of 1 mol / L to prepare a basic electrolyte. The basic electrolyte solution is mixed with the compound represented by the general formula (1) or other compounds at the ratio shown in Table 7, and the electrolyte solution used in Examples 19 and 20 and Comparative Examples 11 to 13 is used. did.

[Manufacture of lithium secondary batteries]
A sheet-like battery was produced in the same manner as in the above example except that the positive electrode and the basic electrolyte were used.

[Evaluation of cycle characteristics]
After confirming the capacity with a constant current corresponding to 0.2 C at 25 ° C. in a state where the lithium secondary battery is sandwiched between glass plates in order to improve the adhesion between the electrodes, a constant current of 2 C at 60 ° C. After charging, the process of discharging at a constant current of 2C was taken as one cycle, and 300 cycles were performed. The discharge capacity retention ratio was calculated from the formula of (discharge capacity at 300th cycle) ÷ (discharge capacity at the first cycle) × 100.

As is clear from Table 7, the batteries using the non-aqueous electrolyte solution according to the present invention (Examples 19 and 20) are the batteries using the non-aqueous electrolyte solution that is not the non-aqueous electrolyte solution according to the present invention (Comparative Example 11). Compared with ˜13), the cycle capacity retention rate is excellent. Thus, it can be seen that any compound represented by the general formula (1) is excellent in the cycle capacity retention rate regardless of which compound is used. On the other hand, in Comparative Example 12 which is a compound having a carbon-carbon double bond outside the ring and Comparative Example 11 which is a compound having a multiple bond in the ring, even if introduced together with a carbonate having a fluorine atom, it is durable. The effect of improving sex is not manifested.
The reason for this is that when a carbonate having a fluorine atom and a compound represented by the general formula (1) are used in combination, a carbonate having a fluorine atom is formed on the electrode protective layer formed by the compound represented by the general formula (1). Although the electrode surface durability is remarkably improved by being taken in and highly crosslinked, as a result, the effect of improving the excellent battery durability performance as described above is exhibited (Examples 19 and 20), but the general formula (1) In the case of using a compound that is not included in the range represented by the above, it is presumed that the stability of the electrode protective layer is low (Comparative Examples 11 and 12).
Furthermore, the effects of the present invention are remarkably shown even when the battery voltage is even higher than in Examples <A> to <D>. From the above, it can be seen that when the non-aqueous electrolyte solution according to the present invention is used, the durability improving effect is exhibited regardless of the electrode design.

<Example F>
[Production of positive electrode]
90% by mass of Li _1.05 Ni _0.5 Mn _1.5 O ₂ as a positive electrode active material, 5% by mass of acetylene black as a conductive material, and 5% by mass of polyvinylidene fluoride as a binder in an N-methylpyrrolidone solvent Mixed and slurried. The obtained slurry was applied to an aluminum foil having a thickness of 15 μm, dried, and rolled with a press. The active material layer was 30 mm in width, 40 mm in length, 5 mm in width, and 9 mm in length. It cut out in the shape which has a process part, and it was set as the positive electrode used for Examples 21, 22 and Comparative Example 14.

[Manufacture of electrolyte]
Under a dry argon atmosphere, a mixture of trans-4,5-difluoroethylene carbonate and bis (2,2,2-trifluoroethyl) carbonate (volume ratio 50:50, Examples 31, 32), and trans-4, A basic electrolyte solution was prepared by dissolving LiPF ₆ dried in a mixture of 5-difluoroethylene carbonate and diethyl carbonate (volume ratio 50:50, Comparative Example 20) to a ratio of 1 mol / L. The basic electrolyte solution was mixed with the compound represented by the general formula (1) at the ratio shown in Table 8 to obtain an electrolyte solution used in Examples 21, 22 and Comparative Example 14.

[Manufacture of lithium secondary batteries]
A sheet-like battery was produced in the same manner as in Example <A> except that the positive electrode and the electrolytic solution were used.

[Evaluation of initial discharge capacity]
The lithium secondary battery was conditioned by a constant current corresponding to 0.3 C at 25 ° C. in a state where the lithium secondary battery was sandwiched between glass plates in order to enhance the adhesion between the electrodes. The battery that had been conditioned was charged at a constant current corresponding to 0.3 C at 25 ° C., and then discharged at a constant current corresponding to 0.3 C to determine the initial discharge capacity.

[Evaluation of high-temperature storage characteristics]
After confirming the capacity with a constant current corresponding to 0.3 C at 25 ° C. in a state where the lithium secondary battery is sandwiched between glass plates in order to enhance the adhesion between the electrodes, a constant current corresponding to 0.3 C is obtained. And stored at 60 ° C. for 72 hours. After cooling the battery to room temperature, discharge at a constant current equivalent to 0.3 C to obtain the discharge capacity, and maintain the capacity from the formula of (discharge capacity after storage) ÷ (discharge capacity before storage) × 100 The rate was determined.

  As is clear from Table 8, the batteries using the non-aqueous electrolyte according to the present invention (Examples 21 and 22) are batteries using a non-aqueous electrolyte that does not contain the compound represented by the general formula (1). Compared to (Comparative Example 14), the capacity retention rate after high-temperature storage is excellent. That is, it can be seen that an effect of improving battery durability is exhibited by using a carbonate having a fluorine atom and the compound represented by the general formula (1) in combination. In addition, the effects of the present invention are remarkably exhibited even when the battery voltage is particularly high as compared with Examples <A> to <E>. From the above, it can be seen that when the non-aqueous electrolyte solution according to the present invention is used, the durability improving effect is exhibited regardless of the electrode design.

  As is clear from the results of the above Examples <A> to <F>, it can be seen that the battery durability is remarkably improved by combining the carbonate having a fluorine atom and the compound represented by the general formula (1). . In particular, even if the battery voltage is different, the effect is tremendous, and it can be understood that the battery durability is improved for a wide range of battery configurations. Moreover, when selecting the carbonate which has a fluorine atom, and the compound of General formula (1), if it was the range prescribed | regulated by this invention, it was shown that any kind of combination expresses an effect.

  According to the non-aqueous electrolyte of the present invention, the non-aqueous electrolyte secondary battery using the non-aqueous electrolyte of the present invention has a high capacity maintenance rate even after a durability test such as a high-temperature storage test or a cycle test. It has excellent output performance and is useful. Therefore, the non-aqueous electrolyte solution of the present invention and the non-non-aqueous electrolyte secondary battery using the same can be used for various known applications. Specific examples include notebook computers, pen input computers, mobile computers, electronic book players, mobile phones, mobile faxes, mobile copy, mobile printers, headphone stereos, video movies, LCD TVs, handy cleaners, portable CDs, minidiscs, etc. , Walkie Talkie, Electronic Notebook, Calculator, Memory Card, Portable Tape Recorder, Radio, Backup Power Supply, Motor, Automobile, Motorcycle, Motorbike, Bicycle, Lighting Equipment, Toy, Game Equipment, Clock, Electric Tool, Strobe, Camera, Load Examples include leveling power sources and natural energy storage power sources.

Claims (8)

A non-aqueous electrolyte comprising a lithium salt and a non-aqueous solvent for dissolving the lithium salt, wherein the non-aqueous electrolyte comprises a carbonate having a fluorine atom and a compound represented by the following general formula (1) A non-aqueous electrolyte characterized by containing.

(In the above general formula (1), X and Z represent CR ¹ ₂ , C═O, C═N—R ¹ , C = P—R ¹ , O, S, N—R ¹ , P—R ¹ . Y may represent CR ¹ ₂ , C═O, S═O, S (═O) ₂ , P (═O) —R ² , P (═O) —OR ³ . In the general formula (1), R and R ¹ are hydrogen, halogen, or a hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and may be the same or different from each other. R ² is an optionally substituted hydrocarbon group having 1 to 20 carbon atoms, R ³ is Li, NR ⁴ _4, or an optionally substituted hydrocarbon group having 1 to 20 carbon atoms. R ⁴ is a hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and may be the same or different, and n and m are each an integer of 0 or more. And the charcoal in the adjacent ring There make further coupled together, may .W be R of the carbon is not reduced by the one in the range of R as defined, W is may be the same or different from each other and the R.) The non-aqueous electrolyte battery according to claim 1, wherein the compound represented by the general formula (1) is a compound represented by the following general formula (2).

(In the general formula (2), Y represents C═O, S═O, S (═O) ₂ , P (═O) —R ² , P (═O) —OR ^3. R ² represents substitution. R ³ is a hydrocarbon group having 1 to 20 carbon atoms which may have a group, and R ³ is Li, NR ⁴ ₄ or a hydrocarbon group having 1 to 20 carbon atoms which may have a substituent. R ⁴ is an optionally substituted hydrocarbon group having 1 to 20 carbon atoms, which may be the same or different. The non-aqueous electrolyte solution according to claim 1 or 2, wherein the carbonate having a fluorine atom is a cyclic carbonate.   The carbonate having a fluorine atom is fluoroethylene carbonate, 4,5-difluoroethylene carbonate, bis (2,2,2-trifluoroethyl) carbonate, or 2,2,2-trifluoroethylmethyl carbonate. Item 4. The non-aqueous electrolyte solution according to any one of Items 1 to 3. The non-aqueous electrolyte solution according to any one of claims 1 to 4, wherein the carbonate having a fluorine atom is contained in the non-aqueous electrolyte solution in an amount of less than 50% by mass. When the content mass of the carbonate having a fluorine atom in the non-aqueous electrolyte is [A] and the content mass of the compound represented by the general formula (1) is [B], [B] / [A] is The non-aqueous electrolyte solution according to any one of claims 1 to 5, wherein the non-aqueous electrolyte solution is 5 to 0.0001.   A non-aqueous electrolyte battery comprising a negative electrode and a positive electrode capable of inserting and extracting lithium ions, and a non-aqueous electrolyte, wherein the non-aqueous electrolyte is the non-aqueous electrolyte according to any one of claims 1 to 6. A non-aqueous electrolyte battery characterized by the above.   The non-aqueous electrolyte battery according to claim 7, wherein the negative electrode capable of inserting and extracting lithium ions is a carbonaceous material.