JPS59196569A - Cell - Google Patents

Abstract

PURPOSE:To obtain a cell having high energy density, high charge/discharge rate, long cycle life, low self-discharge rate and flat discharge voltage by employing macromolecular compound having polyacene structure for the electrode. CONSTITUTION:Macromolecular compound having polyacene structure has such structural formula as shown below (where n is positive integer larger than 5) and may be employed as a film, powder, short fiber, etc. Other conductive material such as graphite, carbon black, acetylene black, metal powder, carbon fiber, etc. may be mixed or a metal mesh may be placed as a current collector. Conductive macromolecular compound produced by doping said macromolecular compound may also be employed for the positive or negative electrode.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a battery in which a polymer compound having a boriacene structure or a leading polymer compound obtained by doping the polymer compound with a dopant is used as a positive electrode and a negative electrode.

Acetylene polymers obtained by polymerizing acetylene using so-called Ziegler-Natsuta catalysts, which are composed of transition metal compounds and organometallic compounds, are useful as electrical and electronic molecules because their electrical conductivity is in the semiconductor region. It is already known that it is an organic semiconductor material.

Methods for producing practical molded products of acetylene high polymers include (a) a method of pressure molding powdered acetylene high polymers;
and (b) a method of obtaining a film-like acetylene polymer having a fibrous microcrystalline (fibril) structure and high mechanical strength by forming it into a film at the same time as polymerization under special polymerization conditions (Tokuko Showa). , !18-32581) was known.

The powdered acetylene polymer molded product obtained by the method (a) above is BF3, BCl3, HClXC12, so2,
When chemically treated with electron-accepting compounds (acceptors) such as No2, HC02, and NO, the electrical conductivity increases by up to three orders of magnitude, and conversely, treated with electron-donating compounds (donors) such as ammonia and methylamine. Then, the electrical conductivity reaches a maximum of 4
It is already known that there is an order of magnitude decrease [D, J, B
Erets et al, Trans, Fara
dySoc, 64, 823 (1968)).

In addition, in the film-like acetylene polymer obtained by the method (b), I, , C4, Br, , ICl, lBrX
By chemically doping with electron-accepting compounds such as AsF5, SbF', PF6, etc. or electron-donating compounds such as NaXK1Li, the electrical conductivity of the acetylene polymer can be freely adjusted over a wide range of 10 = ~103Ω1·CrfLl. It is already known that it can be controlled [J.

C, S, Chem, Commu, , 578 (
1,977), Phys.

Re V, Let t-+ 39+ 1098 (
1,977) + J-Am, S o C-+10
0, 1013 (1,975), J, Chem, P
hys, 69.5098 (1978)). The idea of using this doped film-like acetylene polymer as a material for the positive electrode of primary batteries has already been proposed (Mole C+11a rMetals,
NATOConference 5eries, 5e
ries VI, 47]-489 (1978)).

On the other hand, in addition to the above chemical doping method, electrochemical CIO', PF6', AaF-, AaF,
Anions such as -XCF3-1SOi, BF; etc. and N+ (R/).

CJ, C, S, C
hem, Commu, , 1.979594. C
&ENJan, 26.39 (198)), J.
C, S, Chem, Commu.

1.981.317]. A rechargeable battery using electrochemical doping using a film-like acetylene polymer obtained by the method (b) has been reported (Pa
per Presented at the Inte
rnationalConference on L
ow Dimensional SvntheticM
etals, Hersinger, Denma
rk, 10-15, Augustl, 980)
, This battery can be obtained by the method (b), for example 0,
Two sheets of acetylene polymer film with a thickness of 1 mm were used as positive and negative electrodes, respectively, and when these were immersed in a tetrahydrofuran solution containing lithium iodide and connected to a 9V DC power supply, lithium iodide was electrolyzed. , the acetylene polymer film of the positive electrode is doped with iodine, and the acetylene polymer film of the negative electrode is doped with lithium. This electrolytic doping corresponds to the charging process. When a load is connected to the two doped electrodes, lithium ions and iodine ions react to generate electricity.

In this case, the open circuit voltage (Voc) is 28v1, and the short circuit current density is 5 mA/CTL, and when a tetrahydrofuran solution of lithium perchlorate is used as the electrolyte, the open circuit voltage is 265 ■, and the short circuit current density is approximately It was 3 mA/d.

This battery uses an acetylene polymer as its electrode material, which is easy to reduce weight and size, so it is attracting attention as an inexpensive battery that has high energy density and is easy to reduce weight and size. There is.

In addition, in JP-A-56-136469, in addition to acetylene high polymers, poly(P-phenylene), poly(m-phenylene), poly(phenylene sulfide), poly(phenylacetylene), polypyrrole, etc. are also available. [Disclosed to be useful as an E-electrode material.]

However, the cycles of batteries using the previously known polymer compounds with conjugated double bonds in their main chains as electrode active materials are critical, such as voltage flatness during discharge, charging/discharging efficiency, etc. performance was not always satisfactory.

In view of the above points, the present inventor has developed a system that has high energy density, long cycle life, good charging/discharging efficiency and voltage flatness during discharging, and is easy to reduce weight and size. The present invention was completed as a result of various studies aimed at obtaining an inexpensive battery.

That is, the present invention relates to a battery using a polymer compound having a boriacene structure or a conductive polymer compound obtained by doping the polymer compound with a dopant as a positive electrode and a negative electrode.

The battery obtained by the method of the present invention is a secondary battery using as an electrode a polymer compound having a conjugated double bond in the main chain or a conductive polymer compound obtained by doping the polymer compound with a dopant. Compared to (1) energy density is large. (11) Good voltage flatness during discharge. (iiD less self-discharge. (IV) Charging/
Long life after repeated discharges.

It has the advantage of

The polymer compound having a polyacene structure used in the present invention has the following structure (where n is a positive integer of 5 or more), and a specific example of its manufacturing method is as follows:
Polycondensation of 1-chloro-1-butene [Dokl,.

AI<ad, Nauk 5SSR, ]35 609
(1960)], cyclization and dehydrogenation of 1,2-polybutadiene, polycondensation of β-chlorovinyl ketone [Polym
, Sci, USSR.

2, 477 (196):], but is not necessarily limited to these methods.

The polymer compound having a boriacene structure used in the present invention can be in any form, such as a film, a powder, or a short fiber.

In addition, other suitable conductive materials such as graphite, carbon black,
Acetylene black, metal powder, charcoal As the positive and negative electrodes of the battery of the present invention, not only a polymer compound having a boriacene structure but also a conductive polymer compound obtained by doping the polymer compound with a dopant may be used. I can do it.

As a method for doping a dopant into a polymer compound having a boriacene structure, either chemical doping or electrochemical doping may be employed.

Chemically doping dopants include various conventionally known electron-accepting and electron-donating compounds, such as (I) halogens such as iodine, bromine and bromine iodide, (T'l) pentafluoride; Arsenic, antimony pentafluoride, silicon tetrafluoride, phosphorus pentachloride, phosphorus pentafluoride, aluminum chloride, aluminum bromide, aluminum fluoride, NbR, TaF5, wFa.

Metal halides such as Fe C11s and CdC4, protic acids such as sulfurous acid, perchloric acid, nitric acid, fluorosulfuric acid, trifluoromethanesulfuric acid and chlorosulfuric acid,
Oxidizing agents such as sulfur trioxide, nitrogen dioxide, difluorosulfonyl peroxide, (V) AgC604,
Lacyanoethylene, tetracyanoquinodimethane, Floranil, 2,3-dichloro-5,6-dicyazparabenzoquinone, 2,3-dibromo-5,6-dicyazparabenzoquinone, ■CrO2Cl2, vOC Otsu, fV111
No+5bF6-1NO2+5bF7], NaAsF6
, NO”PF6-1NO2+PF6-1 NO+B
F'4＼ NO+CIO, -, 0 stutter, 4.6 -)
Linitrophenol, 2.4. Examples include alkali metals such as fi - trinitrophenyl sulfone ffi, 2.4.6-trinitrophenylcarboxylic acid, (X)Li, Na, and Ni.

On the other hand, as a dopant to be electrochemically doped, (i) P[, SbF6 z AsF6 N SbC
A halide anion of a group Va element such as #6-, B
F; a halide anion of an element of mal such as I-
(I3-), a dihalogen anion such as Br-1cl-,
Anionic dopants such as perchlorate anions such as ClO (both are effective as dopants to provide P-enriched conductive polymer compounds) and (tt) Li +, K +
, alkali metal ions such as Na+, and cation dopants such as quaternary ammonium ions such as R4N+ (R: a hydrocarbon group having 1 to 21 carbon atoms) (all of which are used as dopants to provide an n-type conductive polymer compound). effective), but is not necessarily limited to these.

Specific examples of compounds providing the above-mentioned anionic dopants and cationic dopants include LiPF6, LiS
bF6, LiAsF, LiCl0a, NaI, NaPF
a, NaSbF6, NaAsF6, NaClO4, K■
, KPF6, KSbF, , KAsF 6, KCl1O
a, C(n B11)4 Na”・(AsFa), [(n B11)4 Na”・(PFa)−1((
n Bu)4 N)"・clo4, LiA7C74, L
Examples include iBF4, but are not necessarily limited to these. These dopants are of one type,
Alternatively, two or more types may be used in combination.

Examples of anion dopants other than the above are I [anion; and examples of cation dopants other than the above are pyrylium or pyridinium cations represented by the following formula (I): (wherein, X is an oxygen atom or nitrogen atom, M is a hydrogen atom or an alkyl group having 1 to 15 carbon atoms, an aryl group having 6 to 15 carbon atoms, I is a halogen atom or an alkyl group having 1 to 10 carbon atoms, and I is a halogen atom or an alkyl group having 1 to 10 carbon atoms; The aryl group m of is 0 when X is an oxygen atom,
is l when is a nitrogen atom. n is 0 or 1-5. ) or the carbonium cation represented by the following formula (r[or
R3 is not a hydrogen atom at the same time), carbon number 1 ~
15 alkyl groups, allyl group, carbon number 6
~15 aryl groups or -oR5
group, provided that L R' represents an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 15 carbon atoms, and is preferably an alkyl group having 1 to 15 carbon atoms, It is an aryl group having 6 to 15 carbon atoms. ] It is.

The HFi anion used usually has the following general formula (■),
Ml or ■; EN -HF211VI MHF211VI [However, in the above formula, R1R" is a hydrogen atom or a carbon number of 1 to
15 alkyl group, aryl having 6 to 15 carbon atoms
l) group, R″ is an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 15 carbon atoms, X is an oxygen atom or a nitrogen atom, and n is 0 or a positive integer of 5 or less. M is an alkali metal] It can be obtained by dissolving a compound (hydrogen fluoride salt) represented by the following as a supporting electrolyte in an appropriate organic solvent. ) Specific examples of compounds include H4N'HF2, BtiwaN-Ya, Na-HF2, K-HF, , Li-HF2
and ' - biryllium or pyridinium cation represented by (I) is a cation represented by formula (I) and CIC):'BF';,klCl;,FeC&-
1SnC41PF; 1PCG, SbF;, AsF
;, CF380311 (obtained by dissolving it in an appropriate organic solvent using a salt with an anion such as F2 as a supporting electrolyte. Specific examples of such salts include Amane and the like.

Specific examples of carbonium cations represented by the above formula (6) or (c, 1H5)3C+, (CIE
(3) 3 C+, the carbonium cation from now on is:
It can be obtained by dissolving them and an anion salt (carbonium salt) in a suitable organic solvent as a supporting electrolyte. Representative examples of anions used here include BF4
-lMC&-1AlBr, Cl''', F6C4,5u
C1) 3-1PF,'.

PCl;, 5bClJ1SbF'6, CIJO;, CF
Specific examples of carbonium salts include (C6H5)3C-BF4.
, (CH3)3C-BF4, HCO・AlCl4,
Examples include HCO-BF4, QH5C0-8nOAi, and the like.

The amount of dopant doped into the polymer compound having a boriacene structure is 2 to 80 mol%, preferably 4 to 60 mol%, particularly preferably 5 to 50 mol%, based on 1 mol of repeating units of the polymer. It is. Even if the amount of the doped dopant is less than 2 mol % or more than 80 mol %, a battery with a sufficiently large discharge capacity cannot be obtained.

The amount of doping can be freely controlled by controlling the amount of electricity that flows during electrolysis. The doping can be carried out either under constant current, constant voltage or under varying conditions of current and voltage. The current value, voltage value, doping time, etc. during doping depend on the type of polymer compound having a boriacene structure used,
It cannot be unconditionally defined because it varies depending on the bulk density, area, type of dopant, type of electrolyte, and required electrical conductivity.

Examples of organic solvents for the electrolyte during electrochemical doping include ethers, ketones, nitriles, amines,
Amides, sulfur compounds, chlorinated hydrocarbons, esters, carbonates, nitro compounds, phosphate ester compounds, sulfolane compounds, etc. can be used, but
Among these, ethers, ketones, nitriles,
Chlorinated hydrocarbons, carbonates, and sulfolane compounds are preferred. Representative examples of these include tetrahydrofuran, 2-methyltetrahydrofuran, ], ]4-dioxaneanisole, monoglyme, acetonitrile, propionitrile, 4-methyl-2-pentanone, butyronitrile, ], ]2-dichloroethane γ-butyrolactone, Examples include dimethoxyethane, methylformate, propylene carbonate, ethylene carbonate, dimethylformamide, dimethyl sulfoxide, dimethylthioformamide, sulfolane, 3-methyl-sulfolane, trimethyl phosphate, triethyl phosphate, etc. It is not limited.

In the battery of the present invention, when a polymer compound having a boriacene structure or a conductive polymer compound obtained by doping the polymer compound with a dopant is used as the positive electrode and the negative electrode, the supporting electrolyte of the electrolyte of the battery is The same method as that used for chemical doping is used, and the doping method is also the same as the above method or a conventionally known method (J
,C,S,.

Chem, Commu, 1.98], 31.
7).

The concentration of the electrolyte used in the battery of the present invention varies depending on the type of polymer compound having a boriacene structure used, charging/discharging conditions, operating temperature, type of electrolyte, type of organic solvent, etc., and should be generally specified in (17). However, it is usually in the range of 0.001 to 10 mol/l, and it can be used even in a supersaturated state.

In the present invention, a polymer compound having a boriacene structure or a conductive polymer compound obtained by doping the polymer compound with a dopant is used as both the positive and negative electrodes of a battery.

In the present invention, if necessary, a porous membrane of synthetic resin such as polyethylene or polypropylene or natural fiber paper may be used as the diaphragm.

Additionally, the cells of the present invention may be thin cells, even paper-thin cells, multiple layers may be stacked on top of each other and coupled together in series or parallel, or a single long cell may be assembled by itself. It may be rolled or spiraled.

A battery using the polymer compound having a boriacene structure of the present invention or the conductive polymer compound obtained by doping the polymer compound with a dopant as both positive and negative electrodes has a high energy density and is rechargeable.・High discharge efficiency, long cycle life, low self-discharge rate, and good voltage flatness during discharge. Further, the battery of the present invention has
It is lightweight, compact, and has a high energy density, making it ideal for portable devices, electric vehicles, gasoline vehicles, and power storage batteries.

EXAMPLES The present invention will be explained in more detail below with reference to Examples and Comparative Examples.

Example 1 [Synthesis of polymer compound having boriacene structure] Pol
ym, Sci, USSR, 2, 477 (1961)
A polymer compound having a boriacene structure was synthesized by polycondensation of β-chlorovinyl ketone according to the method described in . The obtained polymer compound having a boriacene structure was pressure-molded at a pressure of 10 tons/i to obtain a sheet-like molded product.

[Battery experiment]

The polymer compound having a sheet-like polyacene structure obtained by the above method has a width of 0.5 crfL and a length of 2.0 crfL.
Two pieces of cm were cut out and used as a positive electrode and a negative electrode, respectively. The distance between the positive and negative electrodes was set to three. Et
A sulfolane solution having a concentration of 4N-BF4 of 10 mol/l was used as an electrolyte, and charging was performed for 30 minutes under a constant current (05 mA m ). (Doping amount 4.0 mol%
amount of electricity). Immediately after charging is completed, turn off the battery under constant current (
Discharge is carried out at 0.5mA/crl) until the voltage reaches 1.5mA/crl. When the battery reached OV, a repeated charging/discharging test was performed in which charging was performed again under the same conditions as described above, and the number of repetitions was possible up to 296 times.

From the results of the 10th repeated test, the energy density (theoretical energy density) for 1 kg of active material is 1.35.
w -hr / kg, and the charging/discharging efficiency is 93%
Met. Also, when the voltage is 1. The ratio of the amount of electricity discharged until the voltage decreased to 5 V to the total amount of electricity discharged was 93%.

Furthermore, when the battery was left in a charged state for 48 hours, its self-discharge rate was 5%.

Comparative Example 1 [Production of film-like acetylene polymer] Glass reaction volume θ9 with an internal volume of 500 mJ under nitrogen atmosphere
) Add 1.7 ml of titanium tetrabutoxide to a vessel, dissolve in 30 ml of anisole, and then add 2.7 ml of titanium tetrabutoxide.
of triethylaluminum was added with stirring to prepare a catalyst solution.

This reaction vessel was cooled with liquid nitrogen, and the nitrogen gas in the system was exhausted using a vacuum pump. Next, this reaction vessel was
After cooling to 0.degree. C. and keeping the catalyst solution stationary, purified acetylene gas at a pressure of 1 atmosphere was bubbled through.

Immediately, polymerization occurred on the surface of the catalyst solution, producing a film-like acetylene high polymer. 49 minutes after the introduction of acetylene, the acetylene gas in the reaction vessel system was exhausted to stop the polymerization.

After removing the catalyst solution with a syringe under nitrogen atmosphere, -78
It was washed repeatedly with 1.00 ml of purified toluene five times while maintaining the temperature at °C. The film-like acetylene polymer swollen with toluene was a uniform film-like swollen product in which fibrils were tightly intertwined. This swollen product was then vacuum-dried to obtain a reddish-purple film with a metallic luster, a thickness of 85 μm, and a cis content of 98%. In addition, this membranous acetylene (
20) The bulk density of the high polymer is 0.45 g/cc, and its electrical conductivity (DC four-terminal method) is 3.2×10 at 20°C.
-9Ω1·l"".

[Battery experiment]

A battery charge/discharge cycle experiment was conducted in exactly the same manner as in Example 1, except that the film-like acetylene polymer obtained by the above method was used for both the positive and negative electrodes.
Charging became impossible after the 236th repetition. When the film-like acetylene polymer was taken out after the test, it was found that the film had been destroyed, and part of it was analyzed by elemental analysis and infrared spectroscopy, and it was found that it had suffered extensive deterioration. Also,
The electrolyte was also colored brown.

From the results of the 10th repeated test, the theoretical energy density of this battery was 116 w-hr/kg, and the charge/discharge efficiency was 80%. Further, the ratio of the amount of electricity discharged until the voltage decreased to 1.5V during discharge to the total amount of electricity discharged was 86%.

Furthermore, when the battery was left in a charged state for 48 hours, its self-discharge rate was 8%.

Claims (1)

[Claims] A battery in which a polymer compound having a boriacene structure or a conductive polymer compound obtained by doping the polymer compound with a dopant is used as a positive electrode and a negative electrode.