KR20120089111A - CATHODE ACTIVE MATERIAL COMPRISING LITHIUM MANGANESE OXIDE CAPABLE OF PROVIDING EXCELLENT CHARGE-DISCHARGE CHARACTERISTICS AT 3V REGION as Well as 4V Region - Google Patents

Abstract

PURPOSE: A positive electrode active material is provided to improve the low electrochemical performance at 3 V region(2.5-3.5 V). CONSTITUTION: A positive electrode active material comprises lithium manganese oxide as in amorphous status. The positive electrode active material has a spinel structure represented by chemical formula 1. The chemical formula is as follows: Li_(1+y)M_zMn_(2-y-z)O_(4-x)Q_x. In the chemical formula 1, 0=x=1, 0=y=0.3, 0=z=1, M is one or more elements selected from a group consisting of the Al, Mg, Ni, Co, Fe, Cr, V, Ti, Cu, B, Ca, Zn, Zr, Nb, Mo, Sr, Sb, W, Ti and Bi. Q indicates one or more elements selected from a group consisting of N, F, S and Cl.

Description

Cathode Active Material Comprising Lithium Manganese Oxide Capable of Providing Excellent Charge-Discharge Characteristics at 3Ｖ Region as Well as 4Ｖ Region}

The present invention relates to a secondary battery and a positive electrode and a positive electrode active material used therein.

As the development and demand for mobile devices increases, the demand for secondary batteries as energy sources is rapidly increasing. Among them, lithium secondary batteries with high energy density and voltage, long cycle life, and low self discharge rate It is commercially used and widely used.

In addition, as interest in environmental problems grows, research on electric vehicles and hybrid electric vehicles that can replace vehicles using fossil fuels such as gasoline and diesel vehicles, which are one of the main causes of air pollution, is being conducted. . Although a nickel-metal hydride secondary battery is mainly used as a power source of such an electric vehicle and a hybrid electric vehicle, research using a lithium secondary battery having a high energy density and a discharge voltage is being actively conducted, and some commercialization stages are in progress. As a negative electrode active material of such a lithium secondary battery, a carbon material is mainly used, and use of lithium metal, a sulfur compound, etc. is also considered. In addition, lithium-containing cobalt oxide (LiCoO ₂ ) is mainly used as the positive electrode active material, and a lithium-containing manganese oxide such as LiMnO _{2 having a} layered crystal structure and LiMn ₂ O _{4 having a} spinel crystal structure and a lithium- ₂ ) is also considered.

Among the positive electrode active materials, LiCoO ₂ is most used because of its excellent life characteristics and charging and discharging efficiency, but it has a disadvantage in that its price competitiveness is limited because its structural stability is low and it is expensive due to the resource limitation of cobalt used as a raw material. There is a limit to mass use as a power source in fields such as electric vehicles.

The LiNiO ₂ cathode active material exhibits a relatively low cost and high discharge capacity, but exhibits a rapid phase transition of the crystal structure in accordance with the volume change accompanying the charging / discharging cycle, and the safety is significantly lowered when exposed to air and moisture There is a problem.

In addition, lithium manganese oxides such as LiMnO ₂ and LiMn ₂ O ₄ have the advantages of excellent thermal safety and low price, but have a problem of small capacity, poor cycle characteristics, and poor high temperature characteristics.

Among the lithium manganese oxides, spinel-based LiMn ₂ O ₄ exhibits relatively flat potentials in the 4V region (3.7 to 4.3V) and the 3V region (2.7 to 3.1V). However, the cycle and storage characteristics are very poor in the 3V region, making it difficult to utilize them. The reason is that due to the phase transition phenomenon of Jahn-Teller distortion, it exists as a single phase of the cubic phase in the 4V region, but in the 3V region, the complex of the cubic phase and the tetragonal phase The phenomenon which changes in two-phase, the elution phenomenon to the manganese electrolyte solution, etc. are mentioned.

For this reason, when using the 3V region of the spinel-based lithium manganese oxide, the actual capacity is generally lower than the theoretical capacity, and the C-rate characteristics are also low.

Therefore, the study of the utilization of the 3V region of the spinel-based lithium manganese oxide is known to be very difficult to solve the problem, compared to the study of the utilization of the 4V region. Some studies have reported that the cycle characteristics are improved in the 3V region due to the formation of tetragonal phases and the effects of S-doping, respectively, but the effect is insignificant or the reason for the improvement is obvious. Did not reveal.

In addition, Kang and Goodenough et al. (Sun-Ho Kang, John B. Goodenough, et al, Chem. Mater. 2001, 13, 1758-1764) used spinel-based lithium manganese oxide and carbon for milling to utilize the 3V region. In order to improve the cycle characteristics of the 3V region by forming nano grains and strains in lithium manganese oxide in a mixed manner. However, such a technique is also insignificant and does not explain the reason for the improvement of the characteristics.

As confirmed by the inventors of the present application, it has been confirmed that the method proposed by other prior arts, including the above research results, does not exhibit charge and discharge characteristics at a desired level in the 3V region.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made to solve the above-mentioned problems of the prior art and the technical problems required from the past.

After extensive research and extensive experiments, the inventors of the present application have identified the cause for low electrochemical performance in the 3V region (2.5 to 3.5V), and thus, amorphous and spinel specific lithium manganese oxides. In the case of primary granulation, it was confirmed that excellent charge and discharge characteristics can be exhibited not only in the existing 4V region but also in the 3V region.

According to an aspect of the present invention,

As a positive electrode active material containing lithium manganese oxide, the lithium manganese oxide is provided by amorphizing the positive electrode active material, characterized in that it has a spinel structure of the composition represented by the following formula (1).

Li _{1 + y} M _z Mn _{2 -y- z} O _{4 - x} Q _x (1)

In the above formula, 0 = x = 1, 0 = y = 0.3, 0 = z = 1, M is Al, Mg, Ni, Co, Fe, Cr, V, Ti, Cu, B, Ca, Zn, Zr, One or more elements selected from the group consisting of Nb, Mo, Sr, Sb, W, Ti and Bi, and Q is one or more elements selected from the group consisting of N, F, S and Cl.

In addition, the lithium manganese oxide is characterized in that the amorphous by wet milling.

In addition, the lithium manganese oxide is characterized in that it is composed of one or more selected from the cubic phase (cubic phase) and tetragonal phase (tetragonal phase).

The present invention also provides a cathode mixture comprising the cathode active material.

The present invention also provides a cathode for a secondary battery, wherein the cathode mixture is coated on a current collector.

This invention is further characterized by including the said positive electrode for secondary batteries.

The lithium secondary battery is characterized in that it is used as a unit cell of the battery module that is the power source of the medium and large devices.

In addition, the medium-to-large device is characterized in that the electric vehicle, hybrid electric vehicle, plug-in hybrid electric vehicle or power storage system.

On the other hand, the present invention milling a lithium manganese oxide of the spinel structure represented by the formula (1) (S1); It provides a method for producing a positive electrode active material comprising the step of mixing the resultant (S1) and the conductive material, and the binder.

Li _{1 + y} M _z Mn _{2 -y- z} O _{4 - x} Q _x (1)

In the above formula, 0 = x = 1, 0 = y = 0.3, 0 = z = 1, M is Al, Mg, Ni, Co, Fe, Cr, V, Ti, Cu, B, Ca, Zn, Zr, One or more elements selected from the group consisting of Nb, Mo, Sr, Sb, W, Ti and Bi, and Q is one or more elements selected from the group consisting of N, F, S and Cl.

In addition, the milling of the step (S1) is characterized in that the wet milling.

By improving the low electrochemical performance in the 3V region (2.5 to 3.5V), it is possible to provide a cathode active material and a secondary battery including the same, which can exhibit excellent charge and discharge characteristics not only in the existing 4V region but also in the 3V region. .

1 is a result graph showing a change in capacitance according to the voltage of the Examples and Comparative Examples according to the present invention.
2 is a SEM photograph of the positive electrode active material of the embodiment according to the present invention.
Figure 3 is a graph showing the capacity change with increasing cycle of the other examples and comparative examples in the present invention.

The positive electrode active material according to the present invention includes a lithium manganese oxide having a spinel structure of a composition represented by the following Chemical Formula 1, and the lithium manganese oxide is primarily used to exhibit charge and discharge characteristics in the 2.5 to 3.5 V range in addition to the 4 V region. It is characterized by being granulated and amorphous, and in particular, this method is characterized by wet milling.

Li _{1 + y} M _z Mn _{2 -y- z} O _{4 - x} Q _x (1)

In the above formula, 0≤x≤1, 0≤y≤0.3, 0≤z≤1, M is Al, Mg, Ni, Co, Fe, Cr, V, Ti, Cu, B, Ca, Zn, Zr, One or more elements selected from the group consisting of Nb, Mo, Sr, Sb, W, Ti and Bi, and Q is one or more elements selected from the group consisting of N, F, S and Cl.

In general, spinel-based lithium manganese oxide exists as a single phase of the cubic phase in the 4V region (3.7 to 4.3V), but excessive Mn ^{3 +} exists in the 3V region (2.5 to 3.5V), resulting in Jahn-Teller distortion. By the effect, while the phase transition phenomenon from the cubic phase to the tetragonal phase (tetragonal phase), the charge and discharge characteristics are greatly reduced. For example, when the secondary battery is manufactured under the same conditions, the actual capacity in the 4V region is close to the theoretical capacity (theoretical capacity is about 130 mAh / g in both the 3V and 4V regions), but it is typical in the 3V region. The actual capacity (90 mAh / g) falls far short of the theoretical capacity.

As described above, the reason why the charge / discharge characteristic is greatly reduced by the above phase transition phenomenon in the 3V region has not been clearly identified.

However, the inventors of the present application, through various experiments and in-depth studies, for the first time through the computational chemical method that the electrical conductivity of the tetragonal phase is about 25% of the cubic phase The reason for this was confirmed that the tetragonal phase is a structure in which lithium is difficult to be inserted and detached due to the result of the C-axis being increased than the cubic phase.

In the cathode active material according to the present invention, the spinel-based lithium manganese oxide was first granulated and amorphous by milling, thereby surprisingly increasing the actual capacity of the 3V region (2.5 to 3.5V) to the theoretical capacity level. It was. This is a novel fact that is not known in the art at all, and can be said to be an innovative discovery that can maximize the utility of spinel-based lithium manganese oxide.

In particular, it was confirmed that the milling method of primary granulation and amorphization of the spinel-based lithium manganese oxide shows the best life characteristics when wet milling.

As described above, the improvement of the charge-discharge characteristics by wet milling increases the surface area by primary particle formation and amorphization of tetragonal phase lithium manganese oxide which is phase-changed in the 3V band, thereby widening the surface area, and thus lithium is inserted. It is expected that this is because the space that can be further expanded.

As described above, the lithium manganese oxide particles were pulverized to a small size by milling, and as the crystallinity was lowered uniformly, the charge and discharge characteristics in the 3V region were greatly improved.

In particular, in the case of wet milling, both effects as described above are excellent, so that the cathode active material of the present invention is used as the most preferable method for primary granulation and amorphousization.

The cathode active material including lithium manganese oxide according to the present invention reduces the Jahn-Teller distortion effect by reducing the effect of Jahn-Teller distortion by simultaneously making the particle form of lithium manganese oxide into primary particles through post-treatment by wet milling. It inhibits the phase transition from the cubic phase to the tetragonal phase. In addition, by extending the surface area of the tetragonal phase present in the 3V band to widen the insertion region of lithium it is possible to obtain a flat profile at the 3V potential and greatly improve the life characteristics.

Therefore, the spinel-based lithium manganese oxide in the present invention can exhibit the desired level of charge and discharge characteristics in the 3V region by various actions based on the primary granulation and amorphous structure by wet grinding.

In the present invention, the spinel-based lithium manganese oxide may include a cubic phase, a tetragonal phase, or both. That is, the lithium manganese oxide in equiaxed crystal phase or the lithium manganese oxide in tetragonal crystal may be primary granulated and amorphous by wet grinding, and in some cases, lithium manganese oxide including both equiaxed and tetragonal phases. May be primary granulated and amorphous by wet grinding.

The positive electrode active material according to the present invention may further include other active materials in addition to the amorphous or primary granulated spinel lithium manganese oxide as described above, in which case the spinel lithium manganese oxide is preferably based on the total weight of the positive electrode active material. Preferably from 30 to 100%, more preferably from 50 to 100%. Here, the other active materials are various active materials known in the art, such as lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium cobalt-manganese oxide, lithium nickel-manganese oxide, lithium cobalt-nickel oxide, lithium cobalt-manganese- Nickel oxides, oxides in which ellipsoid (s) are substituted or doped, etc. are all included.

The present invention also provides a lithium manganese oxide having a spinel structure, wherein the lithium manganese oxide exhibits charge and discharge characteristics in the range of 2.5 to 3.5 V without having nano grains inside the particles.

Such lithium manganese oxide is a novel material by itself, and can provide excellent charge and discharge characteristics in the 3V region long desired in the art.

The present invention also provides a cathode mixture comprising the cathode active material as described above.

In addition to the positive electrode active material, the positive electrode mixture may optionally include a conductive material, a binder, a filler, and the like.

The conductive material is typically added in an amount of 1 to 50% by weight based on the total weight of the mixture including the positive electrode active material. Such a conductive material is not particularly limited as long as it has electrical conductivity without causing chemical changes in the battery, for example, graphite such as natural graphite or artificial graphite; Carbon black such as carbon black, acetylene black, ketjen black, channel black, furnace black, lamp black, and summer black; Conductive fibers such as carbon fiber and metal fiber; Metal powders such as carbon fluoride, aluminum, and nickel powder; Conductive whiskeys such as zinc oxide and potassium titanate; Conductive metal oxides such as titanium oxide; Conductive materials such as polyphenylene derivatives and the like can be used.

The binder is a component that assists in bonding the active material and the conductive agent to the current collector, and is generally added in an amount of 1 to 50 wt% based on the total weight of the mixture including the positive electrode active material. Examples of such binders include polyvinylidene fluoride, polyvinyl alcohol, carboxymethylcellulose (CMC), starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, polyethylene , Polypropylene, ethylene-propylene-diene terpolymer (EPDM), sulfonated EPDM, styrene butylene rubber, fluorine rubber, and various copolymers.

The filler is optionally used as a component for inhibiting expansion of the positive electrode, and is not particularly limited as long as it is a fibrous material without causing chemical change in the battery. Examples of the filler include olefinic polymers such as polyethylene and polypropylene; Fibrous materials such as glass fibers and carbon fibers are used.

The present invention also provides a positive electrode for a secondary battery in which the positive electrode mixture is coated on a current collector.

The positive electrode for a secondary battery can be produced, for example, by applying a slurry prepared by mixing the positive electrode mixture to a solvent such as NMP, coating the negative electrode collector, followed by drying and rolling.

The cathode current collector is generally made to have a thickness of 3 to 500 mu m. Such a positive electrode current collector is not particularly limited as long as it has conductivity without causing chemical change in the battery. For example, the positive electrode current collector may be formed on a surface of stainless steel, aluminum, nickel, titanium, calcined carbon, or aluminum or stainless steel. The surface-treated with carbon, nickel, titanium, silver, etc. can be used.

The current collector may have fine irregularities on the surface thereof to increase the adhesive force of the cathode active material, and various forms such as a film, a sheet, a foil, a net, a porous body, a foam, and a nonwoven fabric are possible.

The present invention also provides a lithium secondary battery composed of the positive electrode, the negative electrode, the separator, and a lithium salt-containing nonaqueous electrolyte. Lithium secondary battery according to the present invention has the advantage of excellent capacity and cycle characteristics even at 2.5 to 3.5V by including by amorphizing Li _{(1 + x)} Mn ₂ O ₄ by wet milling.

For example, the negative electrode is manufactured by applying a negative electrode mixture including a negative electrode active material on a negative electrode current collector and then drying the negative electrode mixture. The negative electrode mixture may include components as described above, as necessary.

The negative electrode collector is generally made to have a thickness of 3 to 500 mu m. Such an anode current collector is not particularly limited as long as it has high conductivity without causing chemical changes in the battery, and examples thereof include copper, stainless steel, aluminum, nickel, titanium, sintered carbon, copper or stainless steel Surface-treated with carbon, nickel, titanium, silver or the like, aluminum-cadmium alloy, or the like can be used. In addition, like the positive electrode collector, fine unevenness can be formed on the surface to enhance the bonding force of the negative electrode active material, and it can be used in various forms such as films, sheets, foils, nets, porous bodies, foams and nonwoven fabrics.

The separation membrane is interposed between the anode and the cathode, and an insulating thin film having high ion permeability and mechanical strength is used. The pore diameter of the separator is generally 0.01 to 10 mu m and the thickness is generally 5 to 300 mu m. Such separation membranes include, for example, olefinic polymers such as polypropylene, which are chemically resistant and hydrophobic; A sheet or nonwoven fabric made of glass fiber, polyethylene or the like is used. When a solid electrolyte such as a polymer is used as an electrolyte, the solid electrolyte may also serve as a separation membrane.

The lithium salt-containing nonaqueous electrolyte solution is composed of an electrolyte solution and a lithium salt. As the electrolyte solution, a nonaqueous organic solvent, an organic solid electrolyte, and an inorganic solid electrolyte may be used.

Examples of the non-aqueous organic solvent include N-methyl-2-pyrrolidinone, propylene carbonate, ethylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, gamma -Butyrolactone, 1,2-dimethoxyethane, tetrahydroxyfuran, 2-methyltetrahydrofuran, dimethylsulfoxide, 1,3-dioxolane, formamide, dimethylformamide, dioxolane , Acetonitrile, nitromethane, methyl formate, methyl acetate, triester phosphate, trimethoxymethane, dioxolane derivatives, sulfolane, methylsulfolane, 1,3-dimethyl-2-imidazolidinone, propylene carbonate Nonionic organic solvents such as tetrahydrofuran derivatives, ethers, methyl pyrophosphate, ethyl propionate and the like can be used.

Examples of the organic solid electrolyte include a polymer electrolyte such as a polyethylene derivative, a polyethylene oxide derivative, a polypropylene oxide derivative, a phosphate ester polymer, an agitation lysine, a polyester sulfide, a polyvinyl alcohol, a polyvinylidene fluoride, A polymer containing an ionic dissociation group and the like may be used.

As the inorganic solid electrolyte, for example, Li ₃ N, LiI, Li ₅ NI ₂ , Li ₃ N-LiI-LiOH, LiSiO ₄ , LiSiO ₄ -LiI-LiOH, Li ₂ SiS ₃ , Li ₄ SiO ₄ , Nitrides, halides, sulfates, and the like of Li, such as Li ₄ SiO ₄ -LiI-LiOH, Li ₃ PO ₄ -Li ₂ S-SiS ₂ , and the like, may be used.

The lithium salt is a material that is readily soluble in the non-aqueous electrolyte, for example, LiCl, LiBr, LiI, LiClO 4, LiBF 4, LiB 10 Cl 10, LiPF 6, LiCF 3 SO 3, LiCF 3 CO 2, LiAsF _{6, LiSbF 6, LiAlCl 4,} CH 3 SO 3 Li, CF 3 SO 3 Li, (CF 3 SO 2) 2 NLi, chloroborane lithium, lower aliphatic carboxylic acid lithium, lithium tetraphenyl borate and imide have.

For the purpose of improving the charge / discharge characteristics and the flame retardancy, the electrolytic solution is preferably mixed with an organic solvent such as pyridine, triethylphosphite, triethanolamine, cyclic ether, ethylenediamine, glyme, Benzene derivatives, sulfur, quinone imine dyes, N-substituted oxazolidinones, N, N-substituted imidazolidines, ethylene glycol dialkyl ethers, ammonium salts, pyrrole, 2-methoxyethanol, . In some cases, in order to impart nonflammability, a halogen-containing solvent such as carbon tetrachloride or ethylene trifluoride may be further included, and carbon dioxide gas may be further included to improve high temperature storage characteristics, and FEC (Fluoro-Ethylene) may be further included. carbonate), PRS (propene sultone), FEC (Fluoro-Ethlene carbonate) and the like may be further included.

The secondary battery according to the present invention may not only be used in a battery cell used as a power source for a small device, but also preferably used as a unit battery in a medium-large battery module including a plurality of battery cells.

Preferred examples of the medium and large devices include, but are not limited to, electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, power storage systems, and the like.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the following Examples are provided to illustrate the present invention, and the scope of the present invention is not limited thereto.

[Example]

After wet grinding 80 wt% of the spinel lithium manganese oxide, a cathode active material including 5 wt% graphite, 5 wt% dangka black, and 10 wt% PVDF was prepared. A coating spinel lithium manganese oxide wherein the content ratio - _{specifically, Li 1 .1 Mn 1 .805 Al} 0 .095 O 4 of spinel lithium manganese oxide and then Wet milling the graphite content in the ratio, the graphite obtained therefrom A positive electrode mixture was prepared by mixing with denka black and PVDF.

[Comparative Example]

A positive electrode mixture was prepared in the same manner as in Example, except that the spinel lithium manganese oxide of the Example was included as it was without wet grinding.

[Experimental Example]

A positive electrode mixture prepared in Examples and Comparative Examples was added to NMP to make a slurry, and the resultant was rolled and dried to apply a positive electrode current collector to prepare a secondary battery positive electrode. A coin-type lithium secondary battery was manufactured by interposing a separator of porous polyethylene between the positive electrode and the negative electrode based on lithium metal and injecting a lithium electrolyte.

The secondary battery thus produced was repeatedly charged and discharged under 0.1C conditions, and the change in capacity with each cycle was measured.

1 is a graph showing the life characteristics in the 3V voltage band of a secondary battery including a cathode active material prepared in the above Examples and Comparative Examples or by another milling method.

Referring to FIG. 1, in the case of the secondary battery including the cathode active material according to the present invention, the flat level section in the 3V band is much longer, and it can be seen that the life characteristics are the best.

Figure 2 shows a SEM picture of the lithium manganese oxide by wet milling according to the present invention, it can be seen that the effect of the primary granulation and the amorphous phase of the particles in the case of the wet milling than the other milling method. In this way, it can be seen that the greater the degree of primary and amorphous the particles, the greater the life characteristics of the lithium manganese oxide in the 3V band.

Meanwhile, referring to FIG. 3, the secondary battery according to the comparative example has an initial capacity of about 120 mAh / g, but the secondary battery according to the embodiment has an initial capacity of about 230 mAh / g, which is significantly higher than that of the secondary battery of the comparative example. As for the difference in capacity, as the cycle increases, the capacity of the secondary battery according to the embodiment of the present invention decreases slightly, but it can be confirmed that there is still a large difference from the capacity of the secondary battery according to the comparative example.

Claims (10)

A cathode active material containing lithium manganese oxide, wherein the lithium manganese oxide is amorphous and included, and has a spinel structure of a composition represented by the following formula (1):
Li _{1 + y} M _z Mn _{2 -y- z} O _{4 - x} Q _x (1)
In the above formula, 0 = x = 1, 0 = y = 0.3, 0 = z = 1, M is Al, Mg, Ni, Co, Fe, Cr, V, Ti, Cu, B, Ca, Zn, Zr, One or more elements selected from the group consisting of Nb, Mo, Sr, Sb, W, Ti and Bi, and Q is one or more elements selected from the group consisting of N, F, S and Cl. The cathode active material of claim 1, wherein the lithium manganese oxide is amorphous by wet milling. The cathode active material according to claim 1, wherein the lithium manganese oxide is composed of one or more selected from an equibic phase and a tetragonal phase. A cathode mixture comprising the cathode active material according to any one of claims 1 to 3. A positive electrode mixture for secondary batteries, characterized in that the positive electrode mixture according to claim 4 is coated on a current collector. A lithium secondary battery comprising the positive electrode for a secondary battery according to claim 5. The lithium secondary battery of claim 6, wherein the lithium secondary battery is used as a unit cell of a battery module that is a power source of a medium-large device. The lithium secondary battery of claim 7, wherein the medium-to-large device is an electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, or a system for storing power. Milling a lithium manganese oxide of a spinel structure represented by Formula 1 (S1);
Method of producing a positive electrode active material comprising the step of mixing the resultant and the conductive material, and the binder according to (S1).
Li _{1 + y} M _z Mn _{2 -y- z} O _{4 - x} Q _x (1)
In the above formula, 0 = x = 1, 0 = y = 0.3, 0 = z = 1, M is Al, Mg, Ni, Co, Fe, Cr, V, Ti, Cu, B, Ca, Zn, Zr, One or more elements selected from the group consisting of Nb, Mo, Sr, Sb, W, Ti and Bi, and Q is one or more elements selected from the group consisting of N, F, S and Cl. The method of claim 9, wherein the milling of the step (S1) is a method for producing a positive electrode active material, characterized in that the wet milling.

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