KR20080029479A - Cathode active material, lithium secondary battery comprising same, and hybrid capacitor comprising same - Google Patents

Abstract

A positive electrode active material is provided to store an excess of energy for a long time, have improved energy density and output density, and thus be suitable for an energy storage device having high-rate, long-life, and high-capacity characteristics. A positive electrode active material comprises an active material obtained by mixing a first active material with a second active material in a weight ratio of 9.7:0.3-5:5, wherein the first active material includes a compound capable of reversible intercalation/deintercalation of lithium, and the second active material includes a carbonaceous material. The compound capable of reversible intercalation/deintercalation of lithium is a compound represented by the formula 1 of Li_aNi_(1-x-y-z)Co_xMn_yM_zO_(2-delta)P_delta or the formula 2 of Li_aNi_xCo_yMn_(2-x-y-z)M_zO_(4-delta)P_delta.

Description

A positive electrode active material, a lithium secondary battery comprising the same, and a hybrid capacitor including the same {CATHODE ACTIVE MATERIAL, LITHIUM SECONDARY BATTERY COMPRISING SAME, AND HYBRID CAPACITOR COMPRISING SAME}

1 is a graph showing specific discharge capacity according to cycles of cells prepared in Comparative Examples 1 and 2. FIG.

Figure 2 is a graph showing the specific discharge capacity (specific discharge capacity) according to the cycle of the battery prepared in Comparative Example 3.

Figure 3 is a graph showing the specific discharge capacity (specific discharge capacity) according to the cycle of the battery prepared in Examples 1 and 2.

Figure 4a is a discharge curve graph at 10 C-rate of the battery prepared in Example 1, and Comparative Example 1.

4B is a graph of discharge curves at 10 C-rate of the battery prepared in Example 2 and Comparative Example 2. FIG.

5 is a graph showing specific discharge capacity according to cycles at 20 C-rate of the batteries prepared in Examples 1 and 2 and Comparative Examples 1 and 2;

FIG. 6 is a graph showing specific discharge capacity according to cycles at 10 C-rate of the hybrid capacitors prepared in Example 3 and Reference Example 1. FIG.

[Industrial use]

The present invention relates to a positive electrode active material and a lithium secondary battery and a hybrid capacitor including the same, and more particularly, a positive electrode active material having a high rate, a long life and a high capacity characteristic by improving energy density and output density, and a lithium secondary battery and a hybrid including the same. Relates to a capacitor.

[Private Technology]

A non-aqueous electrolyte lithium secondary battery is a capacitor that stores electrical energy by using a reversible intercalation / deintercalation reaction of lithium, and is capable of high capacity charge and discharge. This is a promising energy storage device.

In addition, the nonaqueous electrolyte hybrid capacitor is a capacitor that stores energy by using a reversible intercalation / deintercalation reaction of lithium and a principle of absorbing and desorbing electric charges in an electrical double layer generated at an interface between an electrode and an electrolyte. Charging and discharging is possible and has high capacity. Accordingly, it is promising as an energy storage device for electric vehicles and auxiliary power sources.

A cathode of a conventional nonaqueous electrolyte lithium secondary battery is coated on a metal thin film by mixing an oxide-based cathode active material and a binder made of a polymer and a conductive agent for increasing electrical conductivity at a constant ratio.

It is known that the oxide-based positive electrode active material does not have good electrical conductivity and shows poor characteristics in charge and discharge of high current. Therefore, lithium secondary batteries are difficult to use in devices requiring high current and high power.

Therefore, the present inventor proposes an electrode which improves electrical conductivity and shows excellent capacity increase in high current charge / discharge by mixing a carbon-based cathode active material with an oxide-based cathode active material when fabricating a cathode for a lithium secondary battery, rather than the above-described approach. .

An object of the present invention is to provide a positive electrode active material for energy storage device having a high rate, long life and high capacity characteristics as well as being able to maintain the excess energy for a long time to improve the energy density and output density.

Another object of the present invention is to provide a lithium secondary battery provided with a positive electrode including the positive electrode active material.

Still another object of the present invention is to provide a hybrid capacitor having a positive electrode including the positive electrode active material.

In order to achieve the above object, the present invention provides a first active material comprising a compound capable of reversible intercalation / deintercalation of lithium and a second active material comprising a carbon-based material of 9.7: 0.3 to 5: 5 It provides a positive electrode active material including an active material mixed in a weight ratio.

Preferably, the positive electrode active material is mixed with a first active material containing a reversible intercalation / deintercalation of lithium and a second active material containing a carbon-based material in a weight ratio of 9.5: 0.5 to 5: 5 More preferably in a weight ratio of 9: 1 to 6: 4. In the mixing range, the energy density and the output density of the cathode active material may be improved, thereby improving the high rate, long life, and high capacity characteristics of the lithium secondary battery. In this case, the compound capable of reversible intercalation / deintercalation of lithium may be one compound selected from the group consisting of lithium composite metal oxides, lithium-containing chalcogenide compounds, and mixtures thereof.

In particular, the carbon-based material includes one selected from the group consisting of graphite, activated carbon, hard carbon, soft carbon, carbon fiber, and mixtures thereof.

In addition, the present invention is a positive electrode comprising the positive electrode active material; A negative electrode including a negative electrode active material; And it provides a lithium secondary battery comprising an electrolyte present between them.

In addition, the present invention is a positive electrode comprising the positive electrode active material; A negative electrode including a negative electrode active material; And it provides a hybrid capacitor comprising an electrolyte present between them.

Hereinafter, the present invention will be described in more detail.

The positive electrode active material according to the first embodiment of the present invention uses a first active material containing a compound capable of reversible intercalation / deintercalation of lithium and a second active material containing a carbon-based material.

In this case, the compound capable of reversible intercalation / deintercalation of lithium is a lithium composite metal oxide or a lithium-containing chalcogenide compound. Preferably, the lithium composite metal oxide or lithium-containing chalcogenide compound comprises at least one metal of Ni, Co or Mn, optionally Mg, Al, Cr, V, Ti, Cr, Fe, Zr, Zn And Si, Y, Nb, Ga, Sn, Mo, W, and one metal selected from the group consisting of a combination thereof.

More preferably, the compound capable of reversible intercalation / deintercalation of lithium may be a compound represented by the following formula (1) or (2):

[Formula 1]

Li _a Ni _{1 -xy- z} Co _x Mn _y M _z O _{2 -δ} P _δ

(In Formula 1, M is one element selected from the group consisting of Mg, Al, Cr, V, Ti, Cr, Fe, Zr, Zn, Si, Y, Nb, Ga, Sn, Mo, and W) , 0.95 ≦ a ≦ 1.2, 0 ≦ x ≦ 0.5, 0 ≦ y ≦ 0.5, 0 ≦ z ≦ 0.3, and 0 <δ ≦ 0.1.)

[Formula 2]

Li _a Ni _x Co _y Mn _{2 -xy- z} M _z O _{4 -δ} P _δ

(In Formula 2, M is one element selected from the group consisting of Mg, Al, Cr, V, Ti, Cr, Fe, Zr, Zn, Si, Y, Nb, Ga, Sn, Mo, and W) , P is an element selected from F or S, and 0.95 ≦ a ≦ 1.2, 0 ≦ x ≦ 0.5, 0 ≦ y ≦ 0.5, 0 ≦ z ≦ 0.3, and 0 <δ ≦ 0.1.)

In this case, the compound capable of reversible intercalation / deintercalation of lithium of Formulas 1 and 2 is a spinel compound having a cubic crystal structure.

The carbonaceous material includes one selected from the group consisting of graphite, activated carbon, hard carbon, soft carbon, carbon fiber, and mixtures thereof.

At this time, the hard carbon is preferably prepared by firing a resin selected from the group consisting of phenol resin, furan resin, polyamide resin, and combinations thereof, wherein the soft carbon is coal-based pitch, petroleum-based pitch, coal-based oil, coal tar It is preferable to prepare by firing a carbon precursor selected from the group consisting of, and combinations thereof.

The positive electrode active material is a weight ratio of 9.7: 0.3 to 5: 5, preferably 9.5, of a first active material including a reversible intercalation / deintercalation compound of lithium and a second active material including a carbon-based material. It is mixed in the weight ratio of: 0.5-5: 5, More preferably, it is mixed in the weight ratio of 9: 1-6: 4.

In this case, when the content ratio of the second active material including the carbonaceous material is less than 0.3, the carbonaceous material does not cause a reversible reaction with lithium, and thus does not act as an active material, but acts only as a conductive agent. If exceeded, the reaction between the second active material and lithium is superior to the reaction between the first active material and lithium, and unnecessary reactions such as decomposition of the electrolyte at a high voltage occur, which is not preferable.

A composition for forming a cathode by mixing a mixture of a first active material including a compound capable of reversible intercalation / deintercalation of lithium as the cathode active material and a second active material including a carbon-based material, a premise, and a binder After the preparation, the composition is applied to a positive electrode current collector such as aluminum foil and then rolled to prepare an electrode, preferably an anode.

In this case, the positive electrode may be prepared by mixing 0.1 to 5 parts by weight of the conductive agent and 0.5 to 5.0 parts by weight of the binder with respect to 100 parts by weight of the positive electrode active material. In the present invention, since the carbon-based material is mixed and used as the cathode active material, sufficient electronic conductivity of the cathode may be secured without additionally adding a conductive agent. When the conductive agent is added in the above range, the electron conductivity of the positive electrode can be improved in a range that does not lower the energy density and the output density of the positive electrode active material.

The conductive agent may be used as long as it is an electron conductive material without causing chemical change, and examples thereof include metal powders such as natural graphite, artificial graphite, carbon black, acetylene black, ketjen black, carbon fiber, copper, nickel, aluminum, and silver. Or metal fibers and the like.

In addition, the binder is not particularly limited in the present invention, it is possible to be commonly used in this field. Typically, styrene-butadiene rubber (SBR), polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polyethylene (PE), polypropylene (PP), fluorine-based rubber and the like are possible.

The positive electrode including the positive electrode active material is preferably introduced into the electrode of a lithium secondary battery or a hybrid capacitor.

A lithium secondary battery according to a second embodiment of the present invention includes a positive electrode including the positive electrode active material; A negative electrode including a negative electrode active material; And electrolytes present between them.

In the lithium secondary battery, a separator is disposed between a negative electrode, a positive electrode, the negative electrode, and a positive electrode to manufacture an electrode assembly. The lithium secondary battery is mounted in a case, and an electrolyte is injected to inject the negative electrode, the positive electrode, and the separator into the electrolyte. The lithium secondary battery may be classified into a lithium ion battery, a lithium ion polymer battery, and a lithium polymer battery according to the type of separator and electrolyte used, and may be classified into a cylindrical shape, a square shape, a coin type, a pouch type, and the like. Depending on the size, it can be divided into bulk type and thin film type. Since the structure and manufacturing method of these batteries are well known in the art, detailed description thereof will be omitted.

At this time, the positive electrode is used an electrode containing a positive electrode active material according to the present invention.

The negative electrode includes a negative electrode active material.

As the negative electrode active material, a compound capable of reversible intercalation and deintercalation of lithium may be used. Specific examples of the negative electrode active material include carbonaceous materials such as artificial graphite, natural graphite, graphitized carbon fiber and amorphous carbon, metallic compounds capable of alloying with lithium, or composites containing metallic compounds and carbonaceous materials as negative electrode active materials. Can be used. As a metal which can be alloyed with lithium, Si, Al, Sn, Pb, Zn, Bi, In, Mg, Ga, Cd, Si alloy, Sn alloy, Al alloy, etc. can be illustrated. Moreover, a metal lithium thin film can also be used as a negative electrode active material.

Like the positive electrode, the negative electrode may be prepared by mixing the negative electrode active material, a binder, and optionally a conductive agent to prepare a composition for forming a negative electrode active material layer, and then coating the negative electrode current collector such as copper foil.

As the electrolyte, a non-aqueous electrolyte or a known solid electrolyte may be used, and a lithium salt is used.

The lithium salt is not particularly limited as a lithium salt commonly used in capacitors, for example, LiPF ₆ , LiBF ₄ , LiClO ₄ , Li (CF ₃ SO ₂ ) ₂ , LiCF ₃ SO ₃ , LiSbF _6, or LiAsF ₆ Etc.

Although the solvent of the said non-aqueous electrolyte is not specifically limited, Cyclic carbonates, such as ethylene carbonate, a propylene carbonate, butylene carbonate, vinylene carbonate; Chain carbonates such as dimethyl carbonate, methyl ethyl carbonate and diethyl carbonate; Esters such as methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate and γ-butyrolactone; Ethers such as 1,2-dimethoxyethane, 1,2-diethoxyethane, tetrahydrofuran, 1,2-dioxane and 2-methyltetrahydrofuran; Nitriles such as acetonitrile; Amides, such as dimethylformamide, etc. can be used.

As the electrolyte, a gel polymer electrolyte in which an electrolyte solution is impregnated with a polymer electrolyte such as polyethylene oxide or polyacrylonitrile, or an inorganic solid electrolyte such as LiI or Li ₃ N can be used.

At this time, by using the positive electrode active material according to the present invention as a positive electrode not only solves the problem of dissolving the positive electrode active material by the acid generated by the oxidation of the electrolyte during the charging process of the conventional battery, but also suppress the reaction between the electrolyte solution and the positive electrode active material. As a result, the charge and discharge characteristics, lifespan characteristics, high voltage characteristics, high rate characteristics, and thermal stability of the lithium secondary battery are improved.

In addition, a hybrid capacitor according to a third embodiment of the present invention includes a positive electrode including the positive electrode active material; A negative electrode including a negative electrode active material; And electrolytes present between them.

The hybrid capacitor manufactures an electrode assembly by disposing a separator between a cathode, an anode, the cathode, and an anode, and mounts the separator in a case so that the cathode, the anode, and the separator are impregnated with the electrolyte.

At this time, the positive electrode is used an electrode containing a positive electrode active material according to the present invention.

Activated carbon is used as the negative electrode active material of the negative electrode. The activated carbon is preferably activated carbon in which a carbon material is modified by steam activating treatment, molten KOH activating treatment, or the like, and examples thereof include palm shell activated carbon, phenol based activated carbon, petroleum coke based activated carbon, and the like. May be used alone or in combination of two or more thereof.

At this time, the separator and the electrolyte solution are as described in the first embodiment.

The hybrid capacitor increases capacity and lifespan characteristics even when fast charging and discharging is performed by using the cathode active material according to the present invention as a cathode.

This shows that the conventional electric double layer capacitor has excellent characteristics compared with the case where both the cathode and the anode are using activated carbon. Specifically, the adsorption reaction of the existing electric double layer capacitor can be stored together with the deintercalation reaction of lithium ions. And also lower the self-discharge rate.

Hereinafter, although an Example of this invention is given and this invention is demonstrated in detail, this invention is not limited to these Examples.

Lithium secondary battery

( Example  One)

anode

As a cathode active material Li [Ni Mn _{0 .5 1 .5]} O ₄ and activated carbon. 7: 3 were mixed in a weight ratio of the next, here the zero conductive acetylene black, a binding agent carboxymethylcellulose (CMC) and diene star-butadiene rubber (SBR) was mixed in a weight ratio of 85: 10: 3: 2 to prepare a composition for forming an anode. The positive electrode forming composition was uniformly applied to a 20 μm thick aluminum foil, and vacuum dried at 120 ° C. to prepare a positive electrode.

battery

Using the prepared anode, using a metal lithium as the counter electrode, a porous polyethylene membrane (Celgard ELC, Celgard 2300, thickness: 25㎛) as a separator, ethylene carbonate and diethyl carbonate 1: A coin-type cell was prepared using a liquid electrolyte in which LiPF ₆ was dissolved at a concentration of 1 M in a solvent mixed at a volume ratio of 1.

( Example  2)

A coin-type cell was prepared in the same manner as in Example 1 except that LiBF ₄ was dissolved in a 1 M concentration in a propylene carbonate solvent as a liquid electrolyte.

( Comparative example  One)

As a cathode active material Li [Ni Mn _{0 .5 1 .5]} O ₄ only an anode and a coin-shaped cell except that one of making an electrode, and performed in the same manner as in Example 1 was prepared using.

( Comparative example  2)

A positive electrode and a coin-type cell were prepared in the same manner as in Comparative Example 1, except that LiBF ₄ was dissolved in a 1 M concentration in a propylene carbonate solvent as a liquid electrolyte.

( Comparative example  3)

A positive electrode was prepared using only activated carbon as a positive electrode active material, and a coin-type cell was prepared in the same manner as in Comparative Example 1 except that a liquid electrolyte in which LiBF ₄ was dissolved at a concentration of 1 M in a propylene carbonate solvent was used.

In this case, the types of the positive electrode, the negative electrode, and the electrolyte prepared in Examples 1 to 2 and Comparative Examples 1 to 3 are shown in Table 1 below.

Li [Ni Mn _{0 .5 1 .5]} O ₄ / the content of the non-activated carbon (by weight) Liquid electrolyte Organic solvent Lithium salt Example 1 7: 3 EC / DEC LiBF ₄ Example 2 7: 3 PC LiBF ₄ Comparative Example 1 10: 0 EC / DEC LiBF ₄ Comparative Example 2 10: 0 PC LiBF ₄ Comparative Example 3 0:10 PC LiBF ₄ EC: ethylene carbonate, DEC: diethyl carbonate, PC: propylene carbonate

( Experimental Example  1) Discharge Characteristics at High Current

Discharge characteristics at high currents of the batteries prepared in Examples 1 to 2 and Comparative Examples 1 to 3 were evaluated in the 3.3 to 4.9 V region using an electrochemical analyzer (Toyo System, Toscat 3100U). The results are shown in FIGS. 1 to 3.

1 is a graph showing discharge characteristics at high currents of the batteries prepared in Comparative Examples 1 and 2, FIG. 2 is a graph showing discharge characteristics at high currents of the batteries prepared in Comparative Example 3, and FIG. It is a graph showing the discharge characteristics at high current of the batteries prepared in 1, and 2. Table 2 shows the discharge current density, capacity, and theoretical capacity according to 10 C-rate.

Discharge current density according to 10 C-rate Volume Theoretical capacity Example 1 960 mA / g 53 mAh / g 32.4 mAh / g Example 2 960 mA / g 40 mAh / g 21.9 mAh / g Comparative Example 1 1200 mA / g 42 mAh / g - Comparative Example 2 1200 mA / g 27 mAh / g - Comparative Example 3 750 mA / g 10 mAh / g -

In Table 2, the theoretical capacity of Example 1 was calculated using the formula of Capacity x 0.7 of Comparative Example 1 + Capacity x 0.3 (42 mAh / g x 0.7 + 10 mAh / g x 0.3) of Comparative Example 1, and was performed. The theoretical capacity of Example 2 was calculated using the formula of Capacity x 0.7 of Comparative Example 2 + Capacity x 0.3 (27 mAh / g x 0.7 + 10 mAh / g x 0.3) of Comparative Example 3.

1 and Table 2, the cells of Comparative Examples 1 and 2 have a discharge current density of 24, 60, 120, 240, 600, 1200 mA / g, Comparative Example 1 is 1200 mA / g (10 It can be seen that the capacity of 42 mAh / g is maintained at the discharge current density of C-rate, and the battery of Comparative Example 2 maintains the capacity of 27 mAh / g.

2 and Table 2, the battery of Comparative Example 3 has a discharge current density of 15, 37.5, 75, 150, 375, 750 mA / g, discharge current of 750 mA / g (10 C-rate) Maintain a capacity of 10 mAh / g at density.

3 and Table 2, the batteries of Examples 1 and 2 have a discharge current density of 19.2, 48, 96, 192, 480, 960 mA / g, and the discharge current density increases every 5 cycles. It can be seen. In addition, the battery of Example 1 maintains a capacity of 53 mAh / g at a discharge current density of 960 mA / g (10 C-rate), and the battery of Example 2 maintains a capacity of 40 mAh / g.

In this case, the battery of Example 1 according to the theoretical calculation has a theoretical capacity of 32.4 mAh / g, the battery of Example 2 should have a theoretical capacity of 21.9 mAh / g, as shown above, respectively 53 mAh / g and The high figure was 40 mAh / g. This result is due to indicate a better performance than the original performance due to a positive active material of _{Li [Ni 1/2 Mn 3} /2] O 4 and the carbon-based anode active material, the activated carbon is complementary action.

( Experimental Example  2) 10 C- rate Specific Discharge Characteristics at

The discharge characteristics of the batteries prepared in Examples 1 and 2 and Comparative Examples 1 and 2 were examined.

4A is a discharge curve at 10 C-rate of the battery prepared in Example 1 and Comparative Example 1, and FIG. 4B is a discharge curve at 10 C-rate of the battery prepared in Example 2 and Comparative Example 2. to be.

Referring to FIG. 4A, it was confirmed that the battery prepared in Example 1 including activated carbon as a cathode active material according to the present invention showed superior performance at 10 C-rate than the battery of Comparative Example 1 including no activated carbon. Can be. In addition, referring to Figure 4b, the battery prepared in Example 2 containing activated carbon as a positive electrode active material according to the present invention shows a superior performance at 10 C-rate than the battery of Comparative Example 2 not containing the activated carbon You can see that.

( Experimental Example  3) In the cycle  Specific discharge characteristics

Specific discharge capacities according to cycles of the batteries prepared in Examples 1 and 2 and Comparative Examples 1 and 2 were examined.

FIG. 5 is a graph showing specific discharge capacity according to cycles at 20 C-rate of the batteries prepared in Examples 1 and 2 and Comparative Examples 1 and 2. FIG.

Referring to FIG. 5, it can be seen that the batteries of Examples 1 and 2 including activated carbon as the cathode active material show superior performance compared to Comparative Examples 1 and 2 which do not include the activated carbon according to the present invention.

hybrid  Capacitor

( Example  3) hybrid  Manufacture of capacitors

Li [Ni Mn _{0 .5 1 .5]} O ₄ and the active carbon 7: were mixed in a weight ratio of 3, and then, where the conductive agent of acetylene black, a binder, carboxymethyl cellulose (CMC) and diene star-butadiene rubber (SBR) Was mixed in a weight ratio of 85: 10: 3: 2 to prepare a composition for forming an anode. The positive electrode forming composition was uniformly applied to a 20 μm thick aluminum foil, and vacuum dried at 120 ° C. to prepare a positive electrode.

The capacitor anode prepared above was used, activated carbon was used as a counter electrode, a porous polyethylene membrane (Celgard ELC, Celgard 2300, thickness: 25 µm) was used as a separator, and LiBF ₄ was 1 in propylene carbonate solvent. Coin-type hybrid capacitors were manufactured according to a commonly known manufacturing process using a liquid electrolyte dissolved in M concentration.

( Reference Example  One) hybrid  Manufacture of capacitors

A hybrid capacitor was manufactured in the same manner as in Example 3 except that the activated carbon was not used at the anode.

( Experimental Example  4) Specific Discharge Capacity

In order to determine the discharge capacities of the hybrid capacitors prepared in Example 3 and Reference Example 1, specific discharge capacities were measured according to cycles by charging and discharging each hybrid capacitor at 10 C-rate. .

FIG. 6 is a graph showing specific discharge capacity according to cycles of the hybrid capacitors of Example 3 and Reference Example 1. FIG.

Referring to FIG. 6, it can be seen that the life characteristics of the hybrid capacitors of Example 3 and Reference Example 1 are not significantly different, but have excellent capacity characteristics in high current discharge.

As described above, the lithium secondary battery and the hybrid capacitor having the positive electrode including the carbon-based positive electrode active material were manufactured according to the present invention. Such lithium secondary batteries and hybrid capacitors not only have high rate characteristics but also have high capacity, high efficiency, and long life.

Claims (10)

A cathode active material including an active material in which a first active material including a compound capable of reversible intercalation / deintercalation of lithium and a second active material including a carbon-based material are mixed at a weight ratio of 9.7: 0.3 to 5: 5. . The method of claim 1, The positive electrode active material is a mixture of a first active material including a reversible intercalation / deintercalation of lithium and a second active material containing a carbon-based material in a weight ratio of 9.5: 0.5 to 5: 5 Positive electrode active material. The method of claim 1, The positive electrode active material is a mixture of a first active material containing a compound capable of reversible intercalation / deintercalation of lithium and a second active material containing a carbon-based material in a weight ratio of 9: 1 to 6: 4 Positive electrode active material. The method of claim 1, The compound capable of reversible intercalation / deintercalation of lithium is one type selected from the group consisting of lithium composite metal oxides, lithium-containing chalcogenide compounds, and mixtures thereof. The method of claim 1, A compound capable of reversible intercalation / deintercalation of lithium is a compound represented by the following Chemical Formula 1 or 2: [Formula 1] Li _a Ni _{1 -xy- z} Co _x Mn _y M _z O _{2 -δ} P _δ (In Formula 1, M is one element selected from the group consisting of Mg, Al, Cr, V, Ti, Cr, Fe, Zr, Zn, Si, Y, Nb, Ga, Sn, Mo, and W) , 0.95 ≦ a ≦ 1.2, 0 ≦ x ≦ 0.5, 0 ≦ y ≦ 0.5, 0 ≦ z ≦ 0.3, and 0 <δ ≦ 0.1.) [Formula 2] Li _a Ni _x Co _y Mn _{2 -xy- z} M _z O _{4 -δ} P _δ (In Formula 2, M is one element selected from the group consisting of Mg, Al, Cr, V, Ti, Cr, Fe, Zr, Zn, Si, Y, Nb, Ga, Sn, Mo, and W) , P is an element selected from F or S, and 0.95 ≦ a ≦ 1.2, 0 ≦ x ≦ 0.5, 0 ≦ y ≦ 0.5, 0 ≦ z ≦ 0.3, and 0 <δ ≦ 0.1.) The method of claim 1, The carbon-based material is a positive electrode active material containing graphite, activated carbon, hard carbon, soft carbon and carbon fiber. A positive electrode including a positive electrode active material; A negative electrode including a negative electrode active material; And an electrolyte present between them, A lithium secondary battery comprising the cathode active material according to any one of claims 1 to 6. The method of claim 7, wherein The negative electrode active material may be selected from the group consisting of artificial graphite, natural graphite, graphitized carbon fibers, amorphous carbon, and mixtures thereof; Metallic compounds capable of alloying with lithium; Lithium thin film; And a compound selected from the group consisting of a mixture thereof. A positive electrode including a positive electrode active material; A negative electrode including a negative electrode active material; And an electrolyte present between them, A hybrid capacitor comprising the cathode active material according to any one of claims 1 to 6. The method of claim 9, The negative active material is a hybrid capacitor containing activated carbon.

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