JP6136326B2 - Positive electrode material for lithium ion secondary battery and manufacturing method thereof - Google Patents

Description

  The present invention particularly relates to a lithium manganese composite oxide having a carbon film useful as a positive electrode material of a lithium ion secondary battery and a method for producing the same.

  In recent years, the development of various devices and systems is expected to improve the performance of storage batteries as a power source. In particular, lithium-ion batteries are widely used as secondary batteries that serve as power sources for electronic devices such as portable communication devices and laptop computers. In addition, from the viewpoint of reducing the environmental burden, motor drive batteries and stationary storage batteries for automobiles are also expected rapidly, and further increases in capacity are required.

In lithium ion batteries, lithium cobalt oxide (LiCoO ₂ ) is mainly used as a positive electrode material, but it contains a large amount of rare metal cobalt, which is one of the factors that increase the cost of lithium ion batteries. Yes. In particular, the use of LiCoO ₂ with high cost is difficult because the size of the battery is increased for use in vehicles and the like.

As an alternative material for lithium cobalt oxide, lithium nickel oxide (LiNiO ₂ ), lithium manganese oxide (LiMn ₂ O ₄ ), or the like, which is an inexpensive and resource-rich material, may be used. However, LiNiO ₂ has the problem of reducing the safety of the battery during charging. In addition, LiMn ₂ O ₄ may cause trivalent Mn to elute into the electrolyte during charge / discharge at a high temperature, thereby deteriorating battery characteristics.

In order to solve the problems of increasing the capacity and reducing the cost of lithium ion secondary batteries, a Li ₂ MnO ₃ -based layered Li-rich positive electrode has been studied. Patent Document 1 describes a lithium manganese composite oxide containing Ti in order to prevent elution of Mn. Patent Document 2 describes a lithium ferrite composite oxide containing Fe for further cost reduction. Patent Document 3 describes a method for producing a lithium ferrite composite oxide produced using a manganese compound, an iron compound, and a nickel compound. Patent Document 4 describes a method of coating the surface of particles of electrode material with carbon using an organic compound composed of four benzene rings such as pyrene.

Japanese Patent No. 4963059 Japanese Patent No. 3940788 JP 2006-036621 A JP 2009-245762 A

  However, the methods described in the above-mentioned patent documents are insufficient to overcome the problems of low discharge characteristics and low durability, which tend to be a problem with a layered Li-excess positive electrode, and there is room for improvement. An object of this invention is to provide the positive electrode material which can improve these problems.

One of the embodiments is represented by the composition formula Li _{1 + x} (Fe _y Ni _z Mn _1-yz ) _1-x O ₂ (0 <x <1/3, 0 ≦ y, z <0.6). The present invention relates to a lithium manganese composite oxide having a carbon film, wherein at least a part of the surface of the lithium manganese composite oxide is coated with a carbon film.

  When the lithium manganese composite oxide having a carbon film of this embodiment is used as a positive electrode material, a lithium ion secondary battery having high discharge rate characteristics and high cycle characteristics can be provided.

It is a figure which shows an example of the outline | summary of the manufacturing method of the lithium manganese type complex oxide which has a carbon film of this embodiment.

The lithium manganese composite oxide of the present embodiment has the following formula (1):
_{Li 1 + x (Fe y Ni} z Mn 1-y-z) 1-x O 2 Formula (1)
(In formula (1), 0 <x <1/3, 0 ≦ y, z <0.6)
At least a part of the surface of the lithium manganese composite oxide represented by is covered with a carbon film.

  The compound represented by the formula (1) is a Li-rich lithium manganese composite oxide. In formula (1), y is 0 ≦ y, preferably 0.1 <y, and more preferably 0.1 <y ≦ 0.5. Z is z <0.6, preferably z <0.2, and may be 0.

  In the present embodiment, at least a part (including all) of the surface of the lithium manganese composite oxide represented by the formula (1) is covered with a carbon film. When the lithium manganese based composite oxide has a carbon film, when this is used as an electrode material of a lithium ion secondary battery, the discharge capacity and cycle characteristics are improved. This is presumably because the carbon coating imparts conductivity and improves the discharge characteristics, and further, the elution of metals and the like is suppressed, thereby improving the durability.

  In the present specification, the “lithium manganese composite oxide represented by the formula (1)” may be simply referred to as “lithium manganese composite oxide”. In addition, “porphyrin compound and / or phthalocyanine compound” may be simply referred to as “porphyrin compound and the like”.

  In FIG. 1, an example of the manufacturing method of the lithium manganese type complex oxide which has the carbon film of this embodiment is shown.

  In FIG. 1, first, after a porphyrin compound and / or a phthalocyanine compound is dispersed in a solvent to produce a solution of a polyfin compound or the like, a Li-excess lithium manganese composite oxide represented by the formula (1) is added. ((A) of FIG. 1). Then, the lithium manganese composite oxide is dispersed in the solution with ultrasonic waves and then filtered by suction to obtain a lithium manganese composite oxide in which the porphyrin compound or the like is adsorbed on a part or all of the surface (FIG. 1 (b) (adsorption process)). Since the porphyrin compound is a planar molecule and contains nitrogen, the nitrogen molecule can be efficiently adsorbed on the surface of the lithium manganese composite oxide.

  Subsequently, a heat treatment at, for example, 600 ° C. in an inert atmosphere causes the porphyrin compound adsorbed on the lithium manganese composite oxide to be thermally decomposed and fused with the lithium manganese composite oxide to form a fusion product. ((C) of FIG. 1 (heat treatment process)). In this fusion, a carbide (first carbon film) is formed on the surface of the lithium manganese composite oxide.

  In the present embodiment, a second carbon film may be formed on the lithium manganese composite oxide by a chemical vapor deposition method (CVD method) or the like using a carbon source ((d) in FIG. 1). (CVD process)). In this case, the carbide that is the first carbon film formed on the surface of the lithium manganese composite oxide is used as a starting point, and the second carbon film is efficiently laminated.

  Each of the porphyrin compound and the phthalocyanine compound used in the adsorption step may be a compound having no metal or a complex containing a metal. In the present specification, “metal-free porphyrin compound” and “metal-free phthalocyanine compound” may be simply referred to as “porphyrin complex” and “phthalocyanine complex”, respectively. In the metal-containing porphyrin complex or metal-containing phthalocyanine complex (hereinafter sometimes referred to as “metal-containing complex”), examples of the coordinated metal include Fe, Co, Ni, Cu, and Mg. . In this embodiment, it is preferable to use at least one selected from a porphyrin complex not containing a metal, a phthalocyanine complex not containing a metal, a porphyrin complex containing a metal, and a phthalocyanine complex containing a metal. More than one species may be used in combination. Moreover, the porphyrin compound and the phthalocyanine compound may have a substituent. Although it does not specifically limit as a substituent, A carboxyl group, a carbonyl group, a hydroxyl group, a methyl group, an ethyl group etc. are mentioned.

  Examples of the method for adsorbing the porphyrin compound and / or phthalocyanine compound on the surface of the lithium manganese composite oxide include a liquid phase method and a gas phase method. A method of adsorbing on the surface of the manganese-based composite oxide is preferable. For example, a lithium manganese complex oxide may be dispersed and mixed in a solution in which a porphyrin compound or the like is dissolved, or a porphyrin compound and a lithium manganese complex oxide are added together in a solvent and mixed. Also good. Moreover, after mixing a porphyrin compound etc. and lithium manganese type complex oxide, methods, such as a concentration-drying method and an impregnation method, may be used, and a solvent may be removed by suction filtration. As the solvent used for the adsorption of the porphyrin compound and the like, an aqueous solvent, an organic solvent system and the like can be used. As the organic solvent system, tetrahydrofuran (THF), acetonitrile, dichloromethane and the like are preferable. As the aqueous solvent, sulfuric acid, nitric acid, hydrochloric acid and the like are preferable.

  The mixing ratio of the porphyrin compound or the like and the lithium manganese composite oxide in the adsorption step is not particularly limited, but is preferably 0.1: 99.9 to 20:80, and preferably 1:99 to 10:90 in terms of mass ratio. More preferred. Although the usage-amount of a solvent is not specifically limited, It is preferable to use so that mass concentration of a porphyrin compound etc. may become 1-20 mass% with respect to the total mass of a porphyrin compound etc. and a solvent.

  A first carbon film is formed on at least a part of the surface of the lithium manganese composite oxide by a heat treatment step performed after the adsorption step. The heat treatment step can be performed in an inert gas atmosphere such as argon gas, a nitrogen atmosphere, a hydrogen atmosphere, an atmosphere in which two or more of these gases are combined, or a vacuum atmosphere. In this case, the heat treatment temperature is preferably in the range of 400 to 900 ° C, more preferably in the range of 500 to 650 ° C. If the heating temperature is too low, the porphyrin may not be decomposed. If the heating temperature is too high, the lithium manganese composite oxide may melt and become enlarged. The heat treatment time is not particularly limited, but is preferably 20 minutes or more, preferably 30 minutes or more, more preferably 60 minutes or more, and preferably 3 hours or less.

  In the present embodiment, a second carbon film may be further formed on the lithium manganese composite oxide after the heat treatment. When the lithium manganese composite oxide having the second carbon film is used as the positive electrode material, a lithium ion secondary battery with higher discharge characteristics and cycle characteristics can be produced. The formation of the second carbon film can be performed, for example, by sputtering, arc vapor deposition, chemical vapor deposition, or the like. In particular, the chemical vapor deposition method (CVD method) which is chemical vapor deposition is preferable because the vapor deposition temperature and vapor deposition atmosphere can be easily controlled.

  When using the CVD method, for example, a sample obtained by heat-treating a lithium manganese composite oxide having porphyrin adsorbed as described above (that is, a lithium manganese composite oxide having a first carbon film) is used as an alumina or quartz boat, etc. Or a method of floating or transporting in a gas.

  The carbon source compound in the CVD reaction can be appropriately selected as long as it generates carbon by thermal decomposition. Examples of the carbon source compound that can be used include hydrocarbon compounds such as methane, ethane, ethylene, and acetylene, organic solvents such as methanol, ethanol, benzene, and toluene, and CO. As the atmospheric gas, an inert gas such as argon, nitrogen gas, or a mixed gas of these with hydrogen can be used. The temperature in the CVD reaction is preferably 400 to 900 ° C. The time for performing the CVD treatment is not particularly limited, but is preferably 5 minutes or more, more preferably 20 minutes or more, and preferably 3 hours or less.

  The flow rates of the carbon source and the atmospheric gas during the CVD reaction are not particularly limited, but are preferably in the range of 1 mL / min to 10 L / min. It is preferable that the flow rate of the carbon source is 10 mL / min to 500 mL / min because a more uniform film can be formed. The flow rate of the atmospheric gas is more preferably in the range of 100 mL / min to 1000 mL / min. The pressure is preferably in the range of 10 to 10000 Torr, and more preferably 400 to 850 Torr.

  In the lithium manganese composite oxide having a carbon film obtained according to the present embodiment, the carbon content (the total content of carbon constituting the first carbon film and the second carbon film in the case of having the second carbon film) ) Is preferably more than 0 wt% and 10 wt% or less with respect to the total mass of the lithium manganese composite oxide having a carbon film. If the carbon content is too high, the capacity decreases, which is not practical. The carbon content can be calculated, for example, by measuring the weight of a sample by burning the carbon component in the vicinity of 400 to 500 ° C. in an oxygen atmosphere and reducing the weight.

  In the present embodiment, the lithium manganese composite oxide having the carbon film obtained above can be used as an electrode material of a lithium ion secondary battery, preferably a positive electrode material (positive electrode active material). In the present embodiment, the positive electrode can be produced by forming a positive electrode active material layer including the positive electrode material obtained above, a binder, and, if necessary, a conductive additive on the positive electrode current collector. .

  Examples of the conductive additive include graphite, acetylene black, ketjen black, carbon fiber, carbon nanotube, carbon nanohorn, graphene sheet, etc., one kind may be used alone, or a mixture of two or more kinds of these may be used. May be.

  Examples of the binder include polyvinylidene fluoride (PVdF), vinylidene fluoride-hexafluoropropylene copolymer, vinylidene fluoride-tetrafluoroethylene copolymer, styrene-butadiene copolymer rubber, polytetrafluoroethylene, polypropylene, and polyethylene. , Polyimide, and polyamideimide. As for the quantity of the binder used for a positive electrode, 2-10 mass parts is preferable with respect to 100 mass parts of positive electrode materials (positive electrode active material).

  In this embodiment, a lithium ion secondary battery can be produced by using a negative electrode, a positive electrode including the positive electrode material of the present invention, an electrolyte, a separator, and the like.

  As one aspect of the lithium ion secondary battery of this embodiment, it is formed from a positive electrode current collector made of a metal such as aluminum foil, and a positive electrode active material layer including the positive electrode material of this embodiment provided thereon. And a negative electrode current collector made of a metal such as copper foil and a negative electrode active material layer containing a negative electrode active material provided thereon. The positive electrode and the negative electrode are laminated via a separator made of a nonwoven fabric or a polypropylene microporous film so that the positive electrode active material layer and the negative electrode active material layer face each other. This electrode pair is accommodated in a container formed of an exterior body such as an aluminum laminate film. A positive electrode tab is connected to the positive electrode current collector, a negative electrode tab is connected to the negative electrode current collector, and these tabs are drawn out of the container. An electrolytic solution is injected into the container and sealed. It can also be set as the structure where the electrode group by which the several electrode pair was laminated | stacked was accommodated in the container.

As the electrolytic solution, a nonaqueous solution containing an electrolyte of a lithium salt such as LiPF ₆ , LiClO ₄ , LiBF ₄ , LiAlO ₄ , LiAlCl ₄ , LiSbF ₆ , LiSCN, LiCl, LiCF ₃ SO ₃ is used in a non-aqueous solvent. be able to. These electrolytes may be used alone or in a mixture of two or more.

  Examples of the non-aqueous solvent for the electrolyte include propylene carbonate, ethylene carbonate, dimethyl carbonate, diethyl carbonate, and ethyl methyl carbonate. One type may be used alone, or two or more types may be used in combination.

  As the negative electrode active material, a carbon material typified by graphite, silicon, and a compound thereof can be used, and two or more of these may be mixed and used.

  Hereinafter, the present invention will be described with reference to examples. However, the present invention is not limited to the following examples.

(Production Example 1)
After dissolving a metal-free porphyrin complex (6 mg) in THF (tetrahydrofuran) (20 ml), Li _1.26 Mn _0.52 Fe _0.22 O ₂ (sample A) (400 mg) was mixed and sonicated. Dispersed. Thereafter, the sample was collected by filtering and dried at 100 ° C. under a nitrogen atmosphere for 12 hours. The sample thus obtained was put in an electric furnace and heat-treated at 600 ° C. for 30 minutes in an Ar atmosphere (500 ml / min) to obtain Sample B. As a result of thermogravimetric analysis under an oxygen atmosphere, it was found that the carbon component combusted at around 400 ° C., and from the weight reduction value, it was adsorbed to 2 wt% of carbon relative to the entire sample B.

(Production Example 2)
Sample B produced in Production Example 1 was heated to 700 ° C. in an Ar atmosphere in an electric furnace, and bubbled with Ar gas using toluene as a carbon source, whereby CVD was performed for 15 minutes to obtain Sample C. At this time, the flow rate of Ar was 300 ml / min. Thermogravimetric analysis was performed on the sample C after CVD in an oxygen atmosphere. As a result, it was found that the carbon component burned in the vicinity of 400 ° C. to 500 ° C., and 4 wt% of carbon was adsorbed with respect to the entire sample C from the weight reduction.

(Comparative Example 1)
Using untreated Li _1.26 Mn _0.52 Fe _0.22 O ₂ (sample A) as the positive electrode material, the PVdF as the binder and the carbon black as the conductive additive have a mass ratio (positive electrode material: binder: A paste was prepared using N-methyl-2-pyrrolidinone as a solvent. The obtained paste was applied to an Al foil for a current collector with a thickness of 70 μm. Then, after drying this at 120 degreeC for 1 hour, the electrode was pressure-molded with the roller press and it punched out to ² cm2, and was set as the positive electrode. As the counter electrode, graphite was used. As the electrolyte, LiPF ₆ was mixed at a volume ratio of 1: 6 with 4: 6 ethylene carbonate and dimethyl carbonate. As the separator, a lithium ion secondary battery cell for evaluation was prepared using a polyethylene porous film having a thickness of 30 μm. The obtained lithium ion secondary battery cell was set in a charging / discharging tester, and charging / discharging was performed in a voltage range of 4.8V to 2.0V. Table 1 shows the results of discharging at a current amount of 5 mA / g, 20 mA / g, and 40 mA / g, respectively. Moreover, the capacity maintenance rate after 20 cycles (discharge capacity after 20 cycles with respect to the initial discharge capacity) is also shown in Table 1 (4.5 to 2.0 V, 30 ° C.).

Example 1
Comparative Example 1 except that instead of Sample A, Li _1.26 Mn _0.52 Fe _0.22 O ₂ (Sample B obtained in Production Example 1) heat-treated after adsorption of the porphyrin complex was used as the positive electrode material. Similarly, lithium ion secondary battery cells were produced and evaluated. The results are shown in Table 1.

(Example 2)
As the positive electrode material, Li _1.26 Mn _0.52 Fe _0.22 O ₂ (Sample C obtained in Production Example 2) in which a carbon film was further deposited by CVD after heat treatment was used instead of Sample A. A lithium ion secondary battery cell was prepared and evaluated in the same manner as in Comparative Example 1. The results are shown in Table 1.

  It was found that the use of the sample B or sample C coated with carbon as the positive electrode material improved the reduction in discharge capacity as compared with the case of using the sample A not coated with carbon. Further, the results of Example 1 and Example 2 showed that Example 2 in which carbon was coated by CVD to form a second carbon film had higher characteristics. The capacity retention rate after 20 cycles was also improved in the order of sample A <sample B <sample C. This seems to be a result of the elution of metals and the like being suppressed by the carbon film.

(Production Example 3)
After dissolving Ni-porphyrin complex (6 mg) in THF (20 ml), Li _1.26 Mn _0.52 Fe _0.22 O ₂ (sample A) (400 mg) was mixed and dispersed by ultrasonic treatment. Thereafter, the sample was collected by filtering and dried in a nitrogen atmosphere at 100 ° C. for 12 hours. The obtained sample was put in an electric furnace and heat-treated at 600 ° C. for 30 minutes in an Ar atmosphere (500 ml / min) to obtain sample B ′. As a result of thermogravimetric analysis in an oxygen atmosphere, it was found that the carbon component burned around 400 ° C., and from the weight reduction, 2 wt% of carbon was adsorbed to the entire sample B ′. Moreover, when SEM / EDX evaluated, the surface form did not have a big change by the presence or absence of Ni in a porphyrin complex from SEM observation. However, Ni was detected from the EDX results, and it was found that Ni compounds were present on the surface.

(Production Example 4)
Sample B ′ produced in Production Example 3 was heated to 700 ° C. in an Ar atmosphere under an Ar atmosphere, and CVD was performed for 15 minutes by bubbling with Ar gas using toluene as a carbon source to obtain Sample C ′. At this time, the flow rate of Ar was 300 ml / min. Thermogravimetric analysis in an oxygen atmosphere was performed on the sample C ′ after CVD. As a result, the carbon component burned at around 400 ° C. to 500 ° C., and it was found that 4 wt% of carbon was adsorbed with respect to the entire sample C ′ from the weight reduction.

As a positive electrode material, untreated Li _1.26 Mn _0.52 Fe _0.22 O ₂ (Sample A), Li _1.26 Mn _0.52 Fe _0.22 O ₂ (Sample heat-treated after adsorption of Ni-porphyrin complex) B ′), using Li _1.26 Mn _0.52 Fe _0.22 O ₂ (sample C ′), on which a second carbon film was further deposited by CVD after heat treatment, for evaluation as in Comparative Example 1 above A lithium ion secondary battery cell was prepared and evaluated. When Sample B ′ and Sample C ′ were used, the same results as in Example 1 and Example 2 were obtained, respectively. Therefore, it has been found that the effect of improving the battery characteristics can be obtained even when the positive electrode material in which the carbon film is formed using the Ni-porphyrin complex is used compared with the case of using the positive electrode material having no carbon film. .

(Production Example 5)
Except that Li _1.2 Mn _0.5 Ni _0.3 O ₂ (Sample D) was used in place of Sample A, Sample E was subjected to heat treatment by adsorbing the porphyrin complex to Sample D in the same manner as in Production Example 1. Obtained.

(Production Example 6)
A sample F obtained by coating the sample E with a carbon film by CVD was obtained in the same manner as in the manufacture example 2 except that the sample E obtained in the manufacture example 5 was used instead of the sample B.

(Comparative Example 2)
A lithium ion secondary battery cell was produced and evaluated in the same manner as in Comparative Example 1 except that instead of sample A, sample D was used as the positive electrode material. The results are shown in Table 2.

(Example 3)
A lithium ion secondary battery cell was produced and evaluated in the same manner as in Comparative Example 1 except that instead of sample A, sample E was used as the positive electrode material. The results are shown in Table 2.

Example 4
A lithium ion secondary battery cell was produced and evaluated in the same manner as in Comparative Example 1 except that the sample F was used instead of the sample A as the positive electrode material. The results are shown in Table 2.

  As the lithium manganese-based composite oxide, sample A contains Fe, but sample D contains Ni. Therefore, Comparative Example 2, Example 3 and Example 4 are Comparative Example 1, Although both capacities increased compared to Example 1 and Example 2, it was shown that the relationship between the rate characteristics and the capacity retention rate had the same tendency.

(Supplementary Note) In the present embodiment, the following aspects are also preferable.

(Supplementary Note 1) the composition formula _{Li 1 + x (Fe y Ni} z Mn 1-y-z) 1-x O 2 (0 <x <1 / 3,0 ≦ y, z <0.6) lithium manganese represented by System composite oxide and porphyrin compound and / or phthalocyanine compound are mixed in a solvent, and the temperature is adjusted in an inert atmosphere, a nitrogen atmosphere, a hydrogen atmosphere and a mixed atmosphere of two or more thereof, or in a vacuum atmosphere. The manufacturing method of the lithium manganese type complex oxide which has a carbon film characterized by including the process of heating at 400 degreeC or more and 900 degrees C or less to form a 1st carbon film.

  (Additional remark 2) The manufacturing method of the lithium manganese type complex oxide which has a carbon film of Additional remark 1 characterized by including the process of forming a 2nd carbon film by chemical vapor deposition.

  (Supplementary note 3) A positive electrode for a lithium ion secondary battery including a step of mixing a lithium manganese composite oxide having a carbon film produced by the production method according to Supplementary note 1 or 2, a binder, and a conductive additive. Production method.

(Additional remark 4) It is a manufacturing method of the lithium ion secondary battery which has an electrode element, electrolyte solution, and an exterior body,
A step of producing an electrode element by opposingly arranging a positive electrode for a lithium ion secondary battery manufactured by the manufacturing method according to attachment 3 and a negative electrode;
Encapsulating the electrode element and an electrolyte in an outer package;
A method for producing a lithium ion secondary battery, comprising:

Claims (10)

Following formula (1):
_{Li 1 + x (Fe y Ni} z Mn 1-y-z) 1-x O 2 Formula (1)
(In the formula (1), 0 <x <1/3, 0 ≦ y ≦ 0.5 , 0 ≦ z <0.6 , 1-yz> 0 )
Characterized in that at least part of the surface of the lithium-manganese-based composite oxide is represented in is covered with a carbon-containing film containing a metal derived from a metal and / or metal-containing phthalocyanine complex derived from the metal-containing porphyrin complex lithium manganese composite oxide having a carbon-containing film for lithium-ion secondary battery positive electrode material shall be the. The lithium ion secondary battery according to claim 1, wherein the metal derived from the metal-containing porphyrin complex and / or the metal derived from the metal-containing phthalocyanine complex is at least one selected from Fe, Co, Ni, Cu, and Mg. A lithium manganese composite oxide having a carbon film for a positive electrode material. The carbon content for a lithium ion secondary battery positive electrode material according to claim 1 or 2 , wherein the carbon content is 10 wt% or less based on the total mass of the lithium manganese composite oxide having a carbon film. A lithium-manganese composite oxide having an elementary film. Porphyrin compounds and / or phthalocyanine compounds may be represented by the formula (1):
_{Li 1 + x (Fe y Ni} z Mn 1-y-z) 1-x O 2 Formula (1)
(In the formula (1), 0 <x <1/3, 0 ≦ y ≦ 0.5 , 0 ≦ z <0.6 , 1-yz> 0 )
A process of adsorbing on the surface of the lithium manganese composite oxide represented by (adsorption process),
A lithium ion secondary battery positive electrode including a step (heat treatment step) of forming a first carbon film by heating the lithium manganese composite oxide adsorbed by the porphyrin compound and / or phthalocyanine compound obtained by the adsorption step method for producing a lithium manganese-based composite oxide having a carbon-containing coatings for wood. The porphyrin compound is at least one selected from a metal-free porphyrin complex and a metal-containing porphyrin complex,
The phthalocyanine compound is lithium manganese having a carbon-containing film for lithium-ion secondary battery positive electrode material according to claim 4, characterized in that at least one selected from phthalocyanine complex and metal-containing phthalocyanine complex metal-free Method for producing a composite oxide. Further, lithium manganese having a carbon-containing film for lithium-ion secondary battery positive electrode material according to claim 4 or 5, characterized in that it comprises a step of forming a second carbon film Ri by the chemical vapor deposition method Method for producing a composite oxide . Claims wherein the heat treatment, an inert atmosphere, nitrogen atmosphere, and a hydrogen atmosphere as well as a mixture of two or more under an atmosphere of them or in a vacuum atmosphere, characterized in that the temperature is Ru carried out at 400 ° C. or higher 900 ° C. or less manufacturing method of claim 4 to the lithium-manganese-based composite oxide having a carbon-containing film for lithium-ion secondary battery positive electrode material according to any one of 6. Temperature, lithium-manganese-based composite oxide having a carbon-containing film for lithium-ion secondary battery positive electrode material according to claim 6 or 7, characterized in that at 400 ° C. or higher 900 ° C. or less in the chemical vapor deposition method Manufacturing method . Any positive electrode for a lithium ion secondary battery including a lithium manganese-based composite oxide having a carbon-containing film for lithium-ion secondary battery positive electrode material according to item 1 as a positive electrode material of claim 1 to 3. The lithium ion secondary battery which has a positive electrode for lithium ion secondary batteries of Claim 9 .

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