JP4043853B2 - Method for producing electrode material - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing an electrode material, and more particularly to a method for producing an electrode material suitable for use as an electrode material for a battery and further as a positive electrode material for a lithium ion battery.
[0002]
[Prior art]
In recent years, non-aqueous electrolyte secondary batteries such as lithium ion batteries have been proposed and put into practical use as batteries that are expected to be reduced in size, weight, and capacity.
This lithium ion battery uses a positive electrode active material such as lithium cobaltate (LiCoO ₂ ), lithium nickelate (LiNiO ₂ ), or lithium manganate (LiMn ₂ O ₄ ) as a positive electrode material. There is an excellent feature that the electric power exceeds 4V.
On the other hand, Fe, which is abundant in resources and inexpensive, has attracted attention as a positive electrode material for lithium ion batteries. For example, a phosphoric acid compound represented by LiFePO ₄ has a potential of about 3.3 V with respect to metal Li, and thus can be used as a chargeable / dischargeable positive electrode material.
[0003]
[Problems to be solved by the invention]
However, the conventional lithium ion battery has various problems in the positive electrode material used.
For example, LiCoO ₂ has been pointed out to have problems such as Co toxicity and the like, in addition to the problem that Co reserves are small and expensive.
In addition, LiNiO ₂ has excellent charge / discharge characteristics, but is never cheap, and has many problems such as stability at high temperatures and a sudden deterioration in characteristics due to composition deviation from a constant ratio.
In addition, LiMn ₂ O ₄ has been pointed out to have problems such as elution of Mn at high temperatures and problems of cycle deterioration due to Mn ³⁺ yarn-teller strain.
[0004]
On the other hand, LiFePO ₄ has an excellent point that there is no problem of toxicity to the human body and the environment, but is still insufficient in terms of electromotive force and high capacity compared to lithium compounds such as LiCoO ₂ .
As described above, the conventional positive electrode materials have various problems as described above, and also have a common problem that the current density that can be flowed at the time of charging and discharging of the battery is low, so that it is difficult to increase the output. Yes, it is one of the factors that hinder its practical application.
[0005]
The present invention has been made to solve the above-described problems, and uses low-priced and resource-rich elements to achieve high discharge capacity, stable charge / discharge cycle performance, high fillability, high output, etc. An object of the present invention is to provide a method for producing an electrode material that can be used .
[0006]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present inventors have conducted extensive research, and as a result, the lithium compound used as the positive electrode material has a low electronic conductivity. In order to increase the electronic conductivity of the lithium compound used as the positive electrode material, a plurality of primary particles made of lithium compounds are aggregated to form secondary particles. It has been found that a composite positive electrode material having excellent electronic conductivity can be obtained by interposing an electron conductive material such as carbon between the primary particles.
[0007]
This technical idea will be described further. Li compounds such as LiCoO ₂ , LiNiO ₂ , LiMn ₂ O ₄ , LiFe _1-x M _x PO ₄ (where M is Co, Mn, Ni) are used as positive electrode materials for lithium ion batteries. When Li ⁺ is used, Li ⁺ is desorbed from the positive electrode material by charging the battery, and conversely, Li ⁺ is added to the positive electrode material during discharging. The desorption and addition of Li ⁺ occur from the surface of the particle, but at the same time, reduction and oxidation of transition metal ions such as Co, Ni, Mn, and Fe occur in the electrode material.
[0008]
That is, at the reaction point on the surface of the positive electrode material, the presence of the three components of the positive electrode material, Li ⁺ from the electrolyte, and electrons is necessary. However, in the conventional lithium ion battery, the electron conductivity of the material itself is low, and the electron If the supply capacity of electrons can be increased by adding a substance having electronic conductivity inside the material, the high output of the battery can be achieved. Can be realized.
In particular, in the case of a LiFe _1-x M _x PO ₄ -based material, since the electronic conductivity of the material itself is low, the effect of the present invention is extremely high.
[0009]
Next, features of the method for producing the electrode material of the present invention will be described.
That is, the first electrode material manufacturing method of the present invention has the formula Li _x A _y B _z PO ₄ (where A is at least one selected from Mn, Fe and Ni, and B is Mg, Ca, Sr, Ba, Ti, Zn, B, Al, Ga, In, Si, Ge, Sc, Y, at least one selected from rare earth elements, 0 ≦ x <2, 0 <y <1.5, 0 <z < A method for producing an electrode material in which a plurality of primary particles made of 1.5) are aggregated to form secondary particles, and an electronic conductive material is interposed between the primary particles, and includes Li salt or LiOH FeCl ₂ , FeBr ₂ , Fe (CH ₃ COO) ₂ , MnCl ₂ , Mn (CH ₃ COO) ₂ or NiCl ₂ , B salt, H ₃ PO ₄ , NH ₄ H ₂ PO ₄ or (NH ₄ ) and ₂ HPO _4, electronically conductive material or an electron conductive The precursor of the active substance is reacted in a solution or suspension to obtain a precursor slurry, and then the obtained precursor slurry is spray-dried and granulated. Heat treatment is performed in an inert atmosphere at a temperature of from 1000C to 1000C.
[0010]
It is preferable that the electronic conductive material is simple carbon.
The precursor of the electronic conductive material is preferably an organic compound.
[0011]
The method for producing the second electrode material of the present invention has the formula Li _x A _y PO ₄ (where A is at least one selected from Mn, Fe and Ni, 0 ≦ x <2, 0 <y <1. 5) A method for producing an electrode material in which a plurality of primary particles composed of 5) are aggregated into secondary particles, and an electron conductive substance is interposed between the primary particles, and Li salt or LiOH; and _{FeCl 2, FeBr 2, Fe (} CH 3 COO) 2, MnCl 2, Mn (CH 3 COO) 2 , or NiCl _2, and _{H 3 PO 4, NH 4 H} 2 PO 4 or _{(NH 4)} 2 HPO _4, An electron conductive substance or a precursor of an electron conductive substance is reacted in a solution or suspension to obtain a precursor slurry, and then the obtained precursor slurry is spray-dried and granulated to obtain a precursor slurry. The granulated product obtained is heated to 500 ° C to 1000 ° C. Wherein the heat treatment under inert atmosphere.
It is preferable that the electronic conductive material is simple carbon.
The precursor of the electronic conductive material is preferably an organic compound.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of a method for producing an electrode material of the present invention will be described.
The manufacturing method of the electrode material of this embodiment includes Li, A (where A is at least one selected from Mn, Fe, and Ni ) and B (where B is Mg, Ca, Sr, Ba, Ti). , Zn, B, Al, Ga, In, Si, Ge, Sc, Y, a rare earth element), P, and an electron conductive substance or a precursor of an electron conductive substance Synthesize by reacting in medium or suspension.
[0013]
For A, Mn, Fe, Co, and Ni are preferable, and for B, Mg, Ca, Sr, Ti, Zn, and Al are preferable in terms of high discharge potential, abundant resources, safety, and the like.
Here, examples of the rare earth element include La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu.
[0014]
As A and B, for example, a salt of A, a salt of B, or the like can be used.
The Li, for _example, LiCl, LiCH 3 COO, can be used Li salts such as LiOH. As the Fe, for _example, it can be used _{FeCl 2, FeBr 2, Fe (} CH 3 COO) 2 Fe salt such. Further, Mn, Co, As the Ni or the like, for _example, can be used _{MnCl 2, Mn (CH 3 COO} ) 2, a salt such as NiCl _2. As Al, for example, a salt such as AlCl ₃ can be used. Further, as P, for example, H ₃ PO ₄ , NH ₄ H ₂ PO ₄ , (NH ₄ ) ₂ HPO _4, or the like can be used.
[0015]
In particular, for uniform reaction and coprecipitation after mixing, it is preferable to mix LiOH and H ₃ PO ₄ and then react with a solution containing a salt such as FeCl ₂ or MnCl ₂ . At this time, it is preferable to add an electron conductive substance or a precursor of the electron conductive substance to any solution.
[0016]
As the electronic conductive material, carbon is most preferable from the viewpoint of chemical stability, safety and cost, but metals other than carbon are preferable, and in particular, noble metals such as Au, Pt, Ag, Pd, Ru, Rh, and Ir. Is preferred. Among these, Ag is preferable.
Here, the precursor of the electron conductive substance is an electron conductive substance that is heated by heating in an inert atmosphere or a reducing atmosphere. Metal salts, metal alkoxides, metal complexes and the like are preferably used.
[0017]
As carbon, carbon simple substance or a carbon compound is used.
As the carbon simple substance, for example, carbon black, acetylene black, graphite or the like can be used, and either carbon black or acetylene black is preferable. The primary particle diameter of these carbon simple particles is preferably 1-1000 nm, more preferably 10-200 nm.
[0018]
These raw materials are dissolved or dispersed in a solvent, and the resulting solution or suspension is mixed and reacted and coprecipitated. The obtained precipitate is heat-treated (fired) in an inert atmosphere or a reducing atmosphere to obtain an electrode material.
As the solvent, for example, water, alcohols, ketones and the like can be used, but water is preferable from the viewpoint of ease of use and safety.
The concentration of the raw material components in the solution or suspension is not particularly limited, but is preferably 1 to 30% by weight in order to uniformly react and obtain a good mixed state.
[0019]
Moreover, as a drying method of a deposit, it is preferable to use a spray drying method in order to prevent aggregation and to make spherical particles. Moreover, although heat processing temperature (baking temperature) changes with raw materials to be used, 500-1000 degreeC is preferable, More preferably, it is 600-900 degreeC. The reason is that if the heat treatment temperature (firing temperature) is lower than 500 ° C., the reaction does not proceed sufficiently, unreacted substances remain, the crystallinity also decreases, and it may become amorphous. Moreover, it is because there exists a possibility that a product may fuse | melt and vitrify when it is higher than 1000 degreeC.
[0020]
As the atmosphere for the heat treatment (firing), in particular, when A is Fe, an inert atmosphere such as N ₂ or Ar is preferable, and when it is desired to suppress oxidation more, an inert gas such as N ₂ or Ar is used. A reducing atmosphere obtained by mixing a reducing gas such as H ₂ is preferable.
[0021]
In the production method of the present embodiment, the raw materials of the respective components are mixed in a state of being uniformly dispersed in a solution or suspension, and the reaction occurs. Therefore, the formula Li _x A _y B _z PO ₄ (where A is At least one selected from Cr, Mn, Fe, Co, Ni, Cu, B is Mg, Ca, Sr, Ba, Ti, Zn, B, Al, Ga, In, Si, Ge, Sc, Y, rare earth Primary particles having high uniformity represented by at least one selected from elements, 0 ≦ x <2, 0 <y <1.5, 0 ≦ z <1.5) are obtained.
[0022]
At this time, the electron conductive material or the precursor of the electron conductive material that was uniformly dispersed in the solution or suspension was also taken in during the reaction and was uniformly present in the precipitate of the primary particle precursor. Secondary particles that are incorporated in a state and have an electron conductive substance interposed between the primary particles are obtained. Further, the primary particles are bonded to each other through the electronic conductive material, and each primary particle is covered with the electronic conductive material, and the outside of the secondary particles is also covered with the electronic conductive material.
[0023]
In addition, since the electronic conductive material or the precursor of the electronic conductive material that is taken in attracts each other, the precipitate of the precursor of the primary particles forms a network structure and exists. Therefore, even in the particulate matter obtained by heat-treating (sintering) this precursor precipitate, the electron-conductive material remains in the same structure, and the precursor of the electron-conductive material is heat-treated. Since it sometimes changes to an electronically conductive material, the electronically conductive material still exists in a similar structure.
[0024]
In this case, as long as each raw material component is uniformly dispersed and mixed in a solvent before the reaction to form a uniform reaction system, each component may not be dissolved in the solvent. About a raw material component, it is more preferable that it is what melt | dissolves in a solvent. In addition, if the electron conductive substance or the precursor of the electron conductive substance is also soluble in the solvent, the components are uniformly mixed at the molecular level by dissolving in the solvent, so there is no compositional deviation or variation. Particulate matter is obtained and preferred.
[0025]
When carbon simple substance is used as the electron conductive substance, for example, carbon black, acetylene black, graphite or the like can be used, and in particular, either carbon black or acetylene black is preferable.
[0026]
Moreover, when using a carbon compound as a precursor of an electronically conductive substance, an organic compound can be used. The organic compound is not particularly limited as long as it does not volatilize when heated. For example, polyethylene glycol, polypropylene glycol, polyethyleneimine, polyvinyl alcohol, polyacrylic acid (salt), polyvinyl butyral, polyvinyl pyrrolidone, or a copolymer thereof is preferably used.
In addition, for example, sugars such as sugar alcohol, sugar ester, and cellulose, polyglycerin, polyglycerin ester, sorbitan ester, polyoxyethylene sorbitan, various water-soluble organic surfactants, and the like can be used.
Moreover, if phosphoric acid ester, phosphoric acid ester salt, etc. are used, it can be used as a phosphorus component simultaneously with a carbon component.
[0027]
When an organic compound is used as a precursor when a carbon component is used as an electronic conductive material, when an organic compound soluble in a solvent is used, not only other components but also carbon components are Since the particles are uniformly dispersed and mixed at the level, when the primary particles are aggregated to form secondary particles, three-dimensional network carbon is uniformly present between the primary particles, and a better network is obtained. The above structure is formed. Therefore, as the organic compound, those soluble in a solvent are preferable. In particular, when the solvent is water, a water-soluble organic compound is preferable.
[0028]
According to the electrode material manufacturing method of the present embodiment, Li, A (where A is at least one selected from Cr, Mn, Fe, Co, Ni, Cu), and B (where B is Mg). , Ca, Sr, Ba, Ti, Zn, B, Al, Ga, In, Si, Ge, Sc, Y, at least one selected from rare earth elements), P, and an electron conductive substance or an electron conductivity Since the precursor of the substance is synthesized by reacting in a solution or suspension, the reaction can be performed in a homogeneous reaction system, and the aggregation of the product is prevented by using a spray drying method. Secondary particles obtained by joining primary particles via a three-dimensional network-like electron conductive substance can be easily generated, and spherical particles can be formed.
[0029]
The electrode material obtained by the manufacturing method of the present embodiment has the formula Li _x A _y B _z PO ₄ (where A is at least one selected from Cr, Mn, Fe, Co, Ni, Cu, B is Mg, Ca, Sr, Ba, Ti, Zn, B, Al, Ga, In, Si, Ge, Sc, Y, at least one selected from rare earth elements, 0 ≦ x <2, 0 <y <1.5, A plurality of primary particles of 0 ≦ z <1.5) are aggregated to form secondary particles, and an electron conductive substance is interposed between the primary particles.
[0030]
This electrode material is preferably a secondary particle formed by aggregating a plurality of primary particles coated with an electron conductive substance, and is exposed to the outside of the primary particles constituting the secondary particle. It is preferable that the portion to be covered is also covered with an electronic conductive material. Moreover, it is preferable that primary particles are joined via an electronically conductive substance.
The term “bonded” means that the primary particles are not merely secondary particles in the form of aggregates but at least one secondary particle is formed when the electrode is formed using this material. It means that it is firmly connected to the extent that it behaves as a particle. In the secondary particles, the electron conductive material is preferably in a three-dimensional network.
[0031]
For A, Mn, Fe, Co, and Ni are preferable, and for B, Mg, Ca, Sr, Ti, Zn, and Al are preferable in terms of high discharge potential, abundant resources, safety, and the like.
Here, examples of the rare earth element include La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu.
As the electronic conductive material, carbon is most preferable from the viewpoints of chemical stability, safety and cost, but metals other than carbon are preferable, and in particular, Au, Pt, Ag, Pd, Ru, Rh, Ir, etc. The noble metals are preferred. Among these, Ag is preferable.
[0032]
FIG. 1 is a cross-sectional view showing an example of an electrode material obtained by the method for producing an electrode material according to the present embodiment, in which a plurality of primary particles 1 having the above formula are assembled, and these primary particles 1, 1... Are joined together by a thin-layered electronic conductive material layer 2 having a three-dimensional network shape, and secondary particles 3 having an overall shape such as a spherical shape or a polygonal shape are formed.
[0033]
Here, the average particle diameter of the primary particles is preferably 0.001 to 20 μm, more preferably 0.05 to 2 μm.
The reason is that if the average particle size is smaller than 0.001 μm, the crystal structure may be destroyed due to the volume change due to charge / discharge, and if the average particle size is larger than 20 μm, the electrons inside the particles may be destroyed. This is because there is a shortage of supply amount and the utilization efficiency is lowered.
[0034]
Moreover, it is preferable that the thickness of the electronic conductive material layer 2 is 0.001-1 micrometer, More preferably, it is 0.01-0.2 micrometer.
The reason is that if the thickness is less than 0.001 μm, the electron conductivity is not sufficient, and the amount of electrons supplied is insufficient. If the thickness is more than 1 μm, the ratio of the active material in the electrode material is small. This is because the active material is not effectively used.
[0035]
Moreover, it is preferable that the average particle diameter of a secondary particle is 0.01-200 micrometers, More preferably, it is 0.1-50 micrometers.
The reason is that when the average particle size is smaller than 0.01 μm, a large amount of binder is required when preparing the electrode material mixture, and as a result, the ratio of the active material in the electrode material mixture is reduced, This is because the conductivity of the electrode material mixture also decreases, and when the average particle size is larger than 200 μm, voids are likely to occur in the electrode material mixture.
[0036]
The shape of the secondary particles is preferably spherical. This is because close packing is easy, so that the amount of positive electrode material charged per unit volume increases, and the battery volume can be reduced even with the same capacity.
Moreover, 0.1-30 weight% is preferable and, as for content of the electronic conductive substance contained in one secondary particle, More preferably, it is 1-20 weight%. If the content of the electron conductive material is less than 0.1% by weight, the electron conductivity may not be sufficiently developed. If the content is more than 30% by weight, the amount of the electron conductive material is more than the required amount. This is because the weight and volume density of the positive electrode active material in the particles are reduced.
[0037]
The electronic conductive material contained in the secondary particles does not form a compound with other components. In addition, this electronic conductive substance has the formula Li _x A _y B _z PO ₄ (where A is at least one selected from Cr, Mn, Fe, Co, Ni, Cu, and B is Mg, Ca, Sr, Ba, Ti, Zn, B, Al, Ga, In, Si, Ge, Sc, Y, at least one selected from rare earth elements, 0 ≦ x <2, 0 <y <1.5, 0 ≦ z < 1.5), which is present outside the primary particles, and is greatly different from the one obtained by simply mixing the primary particles of the above formula and the electron conductive substance.
The electronic conductive material is preferably present uniformly in the secondary particles, and is preferably present in a network form between the primary particles.
[0038]
According to the electrode material of the present embodiment, high discharge capacity, stable charge / discharge cycle performance, high fillability, high output, and the like can be realized.
Moreover, if this electrode material is used as a positive electrode material of a lithium ion battery, the obtained lithium ion battery has a high discharge capacity, a stable charge / discharge cycle performance, a high filling property, a high output, and the like.
[0039]
【Example】
EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention concretely, this invention is not limited by these Examples.
For example, in this embodiment, metal Li is used for the negative electrode in order to reflect the behavior of the electrode material itself in the data. However, a negative electrode material such as a carbon material, a Li alloy, or Li ₄ Ti ₅ O ₁₂ may be used. . A solid electrolyte may be used instead of the electrolytic solution and the separator.
[0040]
Example 1
LiOH.H ₂ O and H ₃ PO ₄ are dissolved in pure water so that the substance amount ratio thereof is 1: 1 and the concentration is 0.1 mol / kg (as LiH ₂ PO ₄ ). It was. Further, the concentration of FeCl ₂ · 4H ₂ O was prepared an aqueous solution B of 0.1 mol / kg. Next, a solution in which 2.4 g of acetylene black was dispersed in 1 kg of aqueous solution B and 1 kg of aqueous solution A were mixed to obtain a precursor slurry.
[0041]
Next, the obtained precursor slurry is spray-dried and granulated, and then heat-treated (fired) at 700 ° C. for 24 hours in an N ₂ gas atmosphere, whereby a spherical particle diameter of 0.5 to 2.0 μm. Electrode material powder (A: secondary particles) was obtained.
The electrode material powder (A) had a LiFePO ₄ / C ratio of 80/12 by weight.
[0042]
(Example 2)
A spherical electrode material powder (B: secondary particles) having a particle size of 0.5 to 2.0 μm was used in the same manner as in Example 1 except that 5.7 g of sucrose was dissolved and used instead of acetylene black. Obtained.
Here, when sucrose (C ₁₂ H ₂₂ O ₁₁ ) was regarded as 12C, the LiFePO ₄ / C ratio of the electrode material powder (B) was 80/12 by weight.
[0043]
(Comparative example)
An electrode material powder (C) was obtained in the same manner as in Example 1 except that acetylene black or sucrose was not added to the raw material solution.
[0044]
(Production of lithium ion battery)
92 mg of the obtained powder (A) and 8 mg of polytetrafluoroethylene (PTFE) as a binder were kneaded and rolled to obtain an electrode material mixture film (A). Similarly, 92 mg of the obtained powder (B) and 8 mg of polytetrafluoroethylene (PTFE) as a binder were kneaded and rolled to obtain an electrode material mixture film (B).
Further, 80 mg of the obtained powder (C), 12 mg of acetylene black as a conductive auxiliary agent, and 8 mg of polytetrafluoroethylene (PTFE) as a binder were kneaded and rolled to obtain an electrode material mixture film (C).
[0045]
These films (A) to (C) were pressure-bonded onto a stainless mesh current collector, and then punched into a disk shape having an area of 2 cm ² to obtain positive electrodes of Examples 1 and 2 and a comparative example.
The obtained positive electrode was vacuum-dried, and then batteries of Examples 1 and 2 and Comparative Example were produced using an HS standard cell (manufactured by Hosen Co., Ltd.) in a dry Ar atmosphere.
Metal Li was used for the negative electrode, a porous polypropylene film was used for the separator, and a 1M LiPF ₆ solution (solvent: ethylene carbonate / diethyl carbonate = 1/1) was used for the electrolyte.
[0046]
(Battery charge / discharge test)
A battery charge / discharge test was performed on the batteries of Examples 1 and 2 and the comparative example.
The charge / discharge test was performed at room temperature with a constant current of a cutoff voltage of 3 to 4 V and a current density of 0.5 mAcm ⁻² .
The initial charge / discharge characteristics are shown in FIG. 1, and the charge / discharge cycle test results are shown in FIG.
According to the results of this battery charge / discharge test, the electrode material of this example has a high initial capacity of about 150 mAhg ⁻¹ and excellent cycle characteristics even at a high output of current density: 0.5 mAcm ⁻² . .
[0047]
【The invention's effect】
According to the method for producing an electrode material of the present invention, Li, A (where A is at least one selected from Mn, Fe, Ni ) and B (where B is Mg, Ca, Sr, Ba, Ti, Zn, B, Al, Ga, In, Si, Ge, Sc, Y, at least one selected from rare earth elements), P, and an electron conductive substance or a precursor of an electron conductive substance, Since it is synthesized by reacting in solution or suspension, the reaction can be carried out in a homogeneous reaction system, and the average particle diameter formed by interposing an electron conductive substance between primary particles is 0.01. Secondary particles of ˜200 μm can be generated, and spherical secondary particles can be generated.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an electrode material obtained by a method for producing an electrode material according to an embodiment of the present invention.
FIG. 2 is a graph showing initial charge / discharge characteristics of Examples 1 and 2 and a comparative example of the present invention.
FIG. 3 is a diagram showing charge / discharge cycle test results of Examples 1 and 2 and a comparative example of the present invention.
[Explanation of symbols]
1 Primary particle 2 Electronic conductive material layer 3 Secondary particle

Claims (6)

Wherein _{Li x A y B z PO 4} ( where, A is Mn, Fe, at least one selected from Ni, B is Mg, Ca, Sr, Ba, Ti, Zn, B, Al, Ga, In, Si , Ge, Sc, Y, at least one selected from rare earth elements, a plurality of primary particles composed of 0 ≦ x <2, 0 <y <1.5, 0 <z <1.5) A method for producing an electrode material comprising secondary particles and interposing an electron conductive substance between the primary particles,
Li salt or LiOH, FeCl ₂ , FeBr ₂ , Fe (CH ₃ COO) ₂ , MnCl ₂ , Mn (CH ₃ COO) ₂ or NiCl ₂ , B salt, H ₃ PO ₄ , NH ₄ H ₂ PO ₄ Alternatively, (NH ₄ ) ₂ HPO ₄ and an electron conductive substance or a precursor of an electron conductive substance are reacted in a solution or suspension to obtain a precursor slurry, and then the obtained precursor A method for producing an electrode material, characterized in that the slurry is spray-dried and granulated, and the resulting granulated product is heat-treated in an inert atmosphere at 500 ° C to 1000 ° C.   The method for producing an electrode material according to claim 1, wherein the electron conductive substance is a simple carbon.   The method for producing an electrode material according to claim 1, wherein the precursor of the electron conductive substance is an organic compound. A plurality of primary particles composed of the formula Li _x A _y PO ₄ (where A is at least one selected from Mn, Fe, Ni, 0 ≦ x <2, 0 <y <1.5) A method for producing an electrode material comprising secondary particles and interposing an electron conductive substance between the primary particles,
Li salt or LiOH, FeCl ₂ , FeBr ₂ , Fe (CH ₃ COO) ₂ , MnCl ₂ , Mn (CH ₃ COO) ₂ or NiCl ₂ , H ₃ PO ₄ , NH ₄ H ₂ PO ₄ or (NH ₄ ) ₂ HPO ₄ and an electron conductive substance or a precursor of an electron conductive substance are reacted in a solution or suspension to obtain a precursor slurry, and then the obtained precursor slurry is spray-dried A method for producing an electrode material, wherein the granulated product is heat-treated in an inert atmosphere at 500 ° C to 1000 ° C.   5. The method for producing an electrode material according to claim 4, wherein the electron conductive substance is a simple carbon.   The method for producing an electrode material according to claim 4, wherein the precursor of the electron conductive substance is an organic compound.

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