WO2013029211A1 - Negative electrode material and preparation method therefor - Google Patents

Abstract

Disclosed are a negative electrode material and a preparation method therefor, where the technical problem to be solved is to improve the safety of lithium-ion batteries and to reduce preparation costs. The negative electrode material of the present invention is a composite material consisting of a substrate and a covering layer covering same, where the substrate is a graphite-type material having a carbon content of over 99.9%, the substrate comprises nanopores or nanogaps, and where the covering layer is a carbon material. The preparation method for the negative electrode material of the present invention comprises the following steps: oxidizing/reducing the graphite-type material, and solid-phase coating or liquid-phase coating a soft carbon prone to graphitization or an organic pyrolytic carbon. Compared with the prior art, the present invention controls surface functional groups of a processing layer and/or of the covering layer on the surface of the negative electrode material, thus allowing the processing layer and the covering layer to be thin and uniform, improving the stability and thermal conductivity thereof in electrolytes, and improving the safety of lithium-ion batteries. The negative electrode material is provided with a great capacity, great efficiency, simplified preparation process, and reduced costs for preparing the negative electrode material.

Description

 Electrode anode material and preparation method thereof  Electrode anode material and preparation method thereof

Technical field

The invention relates to an electrode material for a battery and a preparation method thereof, in particular to a negative electrode material for a lithium ion battery and a preparation method thereof.

Background technique

With the rapid development of the national economy and the improvement of people's living standards, China's dependence on crude oil is increasing day by day, which has directly threatened China's energy security. In addition, the price fluctuation of crude oil also directly affects the development of the national economy, forcing people to find and develop new energy sources. The development of power batteries and electric vehicles is placed in an increasingly important position, and the important factor that restricts the large-scale application of electric vehicles is the power battery. Lithium-ion batteries are gradually becoming the first choice for electric vehicles in the next 10 to 20 years due to their high energy density, high voltage, no pollution, long cycle life of more than 500 cycles, fast charging and discharging, and increasingly low production costs. battery. But its disadvantage is that it is more expensive. In addition, the power type lithium ion battery has a large volume and the safety performance is correspondingly deteriorated. It can be seen that price and safety performance are the main bottlenecks restricting the use of lithium-ion batteries as power batteries. The negative electrode material is one of the main materials of the lithium ion battery, and its price has an important influence on the final price of the battery, and its stability and thermal conductivity in the electrolyte also have a great influence on the safety of the battery. The preparation of lithium ion battery anode materials by prior art often requires complicated modification treatment, and the production cost is high, which restricts the development of lithium ion power batteries.

Summary of the invention

The object of the present invention is to provide an electrode negative electrode material and a preparation method thereof, and the technical problem to be solved is to improve the safety of the lithium ion battery and reduce the production cost.

The invention adopts the following technical scheme: an electrode negative electrode material, which is composed of a base body and a coating layer covering the same, wherein the matrix body is a graphite material having a carbon content of 99.9% or more, and the shape is a spherical shape, a long axis and a short axis ratio. It is one or more kinds of spherical blocks and flakes of 1.0 to 4.5. The matrix contains nanopores or nanopores. The size of nanopores or nanopores is 10 to 500 nm, the porosity is 0.5 to 20%, and the true density is 2.0~2.26g/cm ³ ; the coating layer is a non-graphite carbon material, the quality of the coating layer is greater than 0 to 20% of the mass of the matrix; the average particle size D ₅₀ of the composite material is 3.0 to 50.0 μm, The surface area is 1.0 to 20.0 m ² /g, and the compact density of the composite material is 1.50 to 2.15 g/cm ³ ; the graphite material is natural crystalline graphite, natural cryptocrystalline graphite, natural crystalline vein graphite. More than one type of artificial graphite, carbon microspheres, and conductive graphite; the non-graphitic carbon material is an easily graphitized soft carbon, an organic pyrolytic carbon or a vapor deposited carbon; and the easily graphitizable soft carbon is a softening point 30 ~300 °C coal tar pitch, petroleum asphalt, coal tar, petroleum industry One or more of a quality oil and a heavy aromatic hydrocarbon; the organic substance is a high molecular polymer polyvinyl alcohol, polyvinyl chloride, polyethylene glycol, polyethylene oxide, polyvinylidene fluoride, acrylic resin, and polypropylene. One or more of the nitriles, or the polymer conductive polymer is one of polythiophene, polyaniline, polyacetylene, polypyrrole, polyacene, polyphage, polyphenylene, polyphenylene vinyl, and polydiacetylene. the above.

A method for preparing an electrode negative electrode material comprises the following steps: 1. oxidizing/reducing a graphite material, heating the graphite material at a rate of 0.1 to 100 ° C/min, and introducing the flow rate at a rate of 0.05 to 10 m ³ /h; An oxidation/reduction gas or a mixed gas of an oxidation/reduction gas and an inert gas at a temperature of 100 to 1000 ° C; the graphite material is natural crystalline graphite, natural cryptocrystalline graphite, natural crystalline vein graphite, artificial graphite, carbon More than one type of microspheres and conductive graphite; 2. Lowering temperature below 100 ° C, stopping the introduction of an oxidation/reduction gas or a mixed gas of an oxidation/reduction gas and an inert gas; 3. The graphite material after oxidation/reduction treatment is The graphite matrix is subjected to solid phase coating or liquid phase coating of soft carbon or organic pyrocarbon which is easy to graphitize, and is pyrolyzed into non-graphite carbon material to obtain an electrode anode material. The quality of the coating layer is greater than 0 to 20 of the mass of the graphite matrix. %; soft carbon which is easy to graphitize is one or more of coal tar pitch, petroleum tar pitch, coal tar, petroleum industry heavy oil and heavy aromatic hydrocarbon having a softening point of 30 to 300 ° C; the organic matter is high One or more of the sub-polymer polyvinyl alcohol, polyvinyl chloride, polyethylene glycol, polyethylene oxide, polyvinylidene fluoride, acrylic resin, and polyacrylonitrile, or the polymer conductive polymer is polythiophene, poly More than one of aniline, polyacetylene, polypyrrole, polyacene, polyphage, polyphenylene, polyphenylene vinyl and polydiacetylene.

 In the electrode negative electrode material of the present invention, the electrode anode material has a moisture content of 0.1% or less by heating or vacuum drying at 100 ° C or lower.

The electrode negative electrode material of the invention is demagnetized, demagnetized 1 to 20 times, magnetic induction intensity is 3000 to 30000 Gs, processing temperature is 10 to 80 ° C, electromagnetic hammer strike frequency is 3 to 180 times/second, and then sieved. The electrode negative electrode material having an average particle size D ₅₀ of 3.0 to 50.0 μm was obtained.

 In the oxidation/reduction treatment of the graphite-based material of the present invention, the furnace chamber of the oxidized/reduced graphite-based material is rotated at a rotational speed of more than 0 to 20 rpm.

 In the oxidation/reduction treatment of the graphite-based material of the present invention, when the temperature reaches 100 to 1000 ° C, the heat retention is greater than 0 to 6 h.

 The cooling of the present invention adopts a method of introducing compressed air between the furnace wall and the heat conducting layer in the furnace wall or a natural cooling in the furnace.

 The solid phase coated coating material of the invention is 1-20% of the mass of the graphite matrix, and the mixing speed is 100-500. r/min, mixed coating for 5 to 180 minutes, or fusion speed of 500 to 3000 r/min, the gap is 0.01-1.0 cm, the fusion temperature is 20-80 ° C, the fusion coating is 10-200 min, and the temperature is naturally lowered to room temperature.

In the liquid phase coating of the present invention, the graphite substrate is mixed with a liquid phase of a soluble organic substance having a graphite matrix mass of 0.1 to 20%, and mixed and stirred at a rate of 2000 to 8000 r/min for 10 to 120 minutes, and the solvent for mixing the liquid phase is water or The organic solvent, the mass of the solvent is 0.8 to 2.0 times the mass of the graphite matrix, the mixing temperature is 10 to 90 ° C, and the drying treatment is carried out at 80 to 300 ° C for 1 to 30 hours.

A method for preparing an electrode negative electrode material comprises the following steps: 1. oxidizing/reducing a graphite material, heating the graphite material at a rate of 0.1 to 100 ° C/min, and introducing the flow rate at a rate of 0.05 to 10 m ³ /h; Oxidation/reduction gas or a mixed gas of an oxidizing/reducing gas and an inert gas, the temperature reaches 100-1000 ° C, and the heat preservation is greater than 0 to 6 h; 2. The gas phase is coated, and a carbon-containing gas is introduced, and the amount of the gas is 0.05-15 m. ³ / h, after 0.1-5h, the furnace is cooled to below 100 ° C, and the mixed gas of oxidation/reduction gas or oxidation/reduction gas and inert gas is stopped; the carbon-containing gas is methane, acetylene, ethylene, One or more of CO ₂ , natural gas, liquefied petroleum gas, benzene and thiophene.

Compared with the prior art, the surface of the electrode negative electrode material does not adopt a conventional surface coating process, but the surface functional groups of the surface treatment layer and/or the coating layer are controlled, and the treatment layer and the coating layer are thin and uniform. The stability and thermal conductivity in the electrolyte are improved, and the safety of the lithium ion battery is improved. The electrode anode material also has the characteristics of high capacity and high efficiency, and the preparation process is simple, and the cost of the anode material is reduced.

DRAWINGS

1 is an SEM image of an electrode negative electrode material of Example 1.

Fig. 2 is a graph showing charge-discharge ratio capacity-voltage of the electrode negative electrode material of Example 1.

detailed description

The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. The electrode negative electrode material of the invention comprises a composite material composed of a substrate and a coating layer covering the same, and the base material is a graphite material having a carbon content of 99.9% or more, and the spherical element having a spherical shape and a length to short axis ratio of 1.0 to 4.5 is a spherical element. More than one of the shape and the sheet shape, the matrix contains nanopores or nanopores, the size of the nanopores or nanopores is 10 to 500 nm, and the porosity (nanopore or nanopore volume / unit volume of the matrix) is 0.5 to 0.5 20%, the true density is 2.0 to 2.26 g/cm ³ . The coating layer is a non-graphitic carbon material, and the coating layer accounts for more than 0 to 20% of the mass of the substrate. The composite material has an average particle size D ₅₀ of 3.0 to 50.0 μm, a specific surface area of 1.0 to 20.0 m ² /g, and a composite material compact density of 1.85 to 2.15 g/cm ³ .

The graphite-based material is one or more of natural crystalline graphite, natural cryptocrystalline graphite, natural crystalline vein graphite, artificial graphite, carbon microspheres, and conductive graphite.

The non-graphite carbon material is an easily graphitized soft carbon, an organic pyrolytic carbon or a vapor deposited carbon.

The easily graphitizable soft carbon is one or more of coal pitch, petroleum pitch, coal tar, petroleum industry heavy oil, and heavy aromatic hydrocarbon having a softening point of 30 to 300 °C.

The organic substance is a high molecular polymer and a high molecular conductive polymer. The high molecular polymer is one or more selected from the group consisting of polyvinyl alcohol, polyvinyl chloride, polyethylene glycol, polyethylene oxide, polyvinylidene fluoride, acrylic resin, and polyacrylonitrile. The polymer conductive polymer is one or more of polythiophene, polyaniline, polyacetylene, polypyrrole, polyacene, poly pheno, polyphenylene, polyphenylene vinyl and polydiacetyl.

In the method for preparing an electrode negative electrode material of the present invention, the electrode negative electrode material is obtained by performing oxidation/reduction, modified coating, and magnetic removal screening steps on the graphite material, including the following steps:

1. Oxidation and / or reduction treatment of graphite materials, graphite materials with a particle size of 2.8 ~ 45.0μm are placed in the furnace cavity of the rotary furnace, and the furnace cavity is rotated at 0 to 20 rpm, at a speed of 0.1 to 100 ° C / min. At the same time, the oxidation/reduction gas or the mixed gas of the oxidation/reduction gas and the inert gas is introduced at a flow rate of 0.05 to 10 m ³ /h, and when the temperature reaches 100 to 1000 ° C, the temperature is maintained for 0 to 6 hours to oxidize the graphite-based material. /Restore processing.

The graphite-based material is one or more of natural crystalline graphite, natural cryptocrystalline graphite, natural crystalline vein graphite, artificial graphite, carbon microspheres, and conductive graphite.

The oxidizing and/or reducing gas is oxygen, air, chlorine Cl ₂ , bromine Br ₂ or fluorine gas F ₂ , and the inert gas is nitrogen or argon.

2. Adopting a method of cooling air between the furnace wall and the heat conducting layer in the furnace wall to reduce the temperature or the natural cooling in the furnace to below 100 ° C, stopping the introduction of the oxidation/reduction gas or the oxidation/reduction gas and the inert gas. The mixed gas gives a graphite matrix.

3. The graphite substrate after oxidation and/or reduction treatment is coated in a solid phase, a liquid phase or a gas phase to obtain a composite material. The quality of the coating material precursor is greater than 0 to 20% of the mass of the graphite matrix, and the moisture content of the anode material is controlled to be less than 0.1% by heating below 100 ° C, vacuum drying or other prior art techniques.

1. Solid phase coating, the precursor of the coating material is 1% to 20% of the mass of the graphite matrix, and the mixing speed of the prior art is 100-500. r/min, mixed coating for 5 to 180 minutes, or put the mixture into the prior art fusion machine, the fusion speed is 500-3000 r/min, the gap is 0.01-1.0 cm, the fusion temperature is 20-80 ° C, the fusion coating is 10-200 min, and the temperature is naturally lowered to room temperature. It is heat-treated at 100 to 3000 ° C according to the prior art and pyrolyzed into a non-graphitic carbon material. The precursor of the coating material is soft carbon which is easy to graphitize, and the soft carbon which is easy to graphitize is one of coal pitch, petroleum pitch, coal tar, heavy oil of heavy petroleum industry and heavy aromatic hydrocarbon with softening point of 30-300 °C. the above.

2. Liquid phase coating, mixing the graphite matrix with the soluble organic matter of the graphite matrix mass of 0.1-20%, mixing and stirring at a speed of 2000-8000r/min for 10 to 120 minutes using a high-speed mixing barrel of the prior art to obtain a mixture. . The solvent used is water or an organic solvent. The mass of the solvent is 0.8 to 2.0 times the mass of the graphite matrix, and the mixing temperature is 10 to 90 ° C. The drying process is carried out at 80 to 300 ° C for 1 to 30 hours. It is heat-treated at 100 to 3000 ° C according to the prior art and pyrolyzed into a non-graphitic carbon material. The coating material is an organic polymer and a polymer conductive polymer. The high molecular polymer is one or more selected from the group consisting of polyvinyl alcohol, polyvinyl chloride, polyethylene glycol, polyethylene oxide, polyvinylidene fluoride, acrylic resin, and polyacrylonitrile. The polymer conductive polymer is one or more of polythiophene, polyaniline, polyacetylene, polypyrrole, polyacene, poly pheno, polyphenylene, polyphenylene vinyl and polydiacetyl.

3. Gas phase coating is to directly pass carbon-containing gas after oxidation/reduction treatment of graphite materials. The amount of gas is 0.05-15m3/h and the temperature is naturally lowered to below 100 °C after 0.1-5h. a mixed gas of an oxidizing/reducing gas or an oxidizing/reducing gas and an inert gas, and the gas-phase-coated precursor, that is, a carbon-containing gas, is methane, acetylene, ethylene, CO ₂ , natural gas, liquefied petroleum gas, benzene, and thiophene. More than one.

4. Demagnetization of the composite material, demagnetization 1 to 20 times, magnetic induction intensity of 3000 to 30000 Gs, processing temperature of 10 to 80 ° C, electromagnetic hammer strike frequency of 3 to 180 times / sec, and then screening to obtain an average The particle size D ₅₀ was 3.0 to 50.0 μm to obtain an electrode negative electrode material.

When the graphite material is subjected to oxidation/reduction treatment, when the temperature reaches 100 to 1000 ° C and the temperature is maintained for 0 to 6 hours, nanopores or nanopores are formed in the matrix material, and the micropores or pores can improve the conductivity of the electrode material.

 The electrode negative electrode material obtained in the examples was observed using a Hitachi Hitachi S4800 scanning electron microscope SEM.

The anode of the experimental battery is prepared by using the electrode anode material prepared by the invention, and the electrode anode material and the polyvinylidene fluoride and the conductive carbon black are dissolved in N-methylpyrrolidone according to a mass ratio of 98:2, and the mass concentration is 10%. The mixed slurry was uniformly coated on a 10 μm thick copper foil, pressed into a sheet, and then formed into a carbon film having a diameter of 1 cm, and dried in a drying oven at 120 ° C for 12 hours. The pole piece prepared above is used as a working electrode, and the lithium metal piece is used as an auxiliary electrode and a reference electrode, and LiPF _{6 having} a concentration of 1 mol/L made of EC, DMC, and EMC solvent mixed in a volume ratio of 1:1:1 is used. Electrolyte, an analog battery having an inner diameter of Ф12 mm was prepared in an argon-filled glove box. The battery charge and discharge test was carried out on the blue battery test system CT2001C of Wuhan Jinnuo Electronics Co., Ltd. The charge and discharge voltage range was 0.01V~2.0V, the current was 0.2C, and the lithium ion battery graphite according to GB/T 24533-2009 The anode material test method tests capacity and efficiency.

 The thermal stability of the battery was examined by the capacity retention rate of 1 C charge and discharge at a high temperature of 45 ° C. The higher the capacity retention rate, the better the thermal stability.

The process parameters of Examples 1-6 and Comparative Example 1 are listed in Table 1. For convenience of comparison, the demagnetization process parameters of Examples 1-6 and Comparative Example 1 were the same. The electrical property test results of Examples 1-6 and Comparative Example 1 are shown in Table 2.

As shown in Fig. 1, the graphite substrate D ₅₀ = 19.2 um material was subjected to surface oxidation/reduction treatment, and then liquid phase coated with 0.5% polypyrrole, and the specific surface area of the material obtained after heat treatment at 150 ° C was 5.26 m ² /g, powder. The compaction is 1.90 g/cm ³ , and the SEM shows that the graphite matrix particles are spherical and spheroidal in shape, the surface oxidation and/or reduction treatment layer and the coating layer are uniform, and the surface groups are reduced due to oxidation and/or reduction treatment on the surface. , the reaction at a low potential is reduced, the thermal stability in the electrolyte is good, the side reaction of the electrolyte and the oxidation and/or reduction treatment layer and the surface of the coating layer is small, the SEI film is stable, and the temperature of the solid battery is high. The cycle is good. The capacity retention at 100 ° C for 100 weeks was 95%.

 As shown in Fig. 2, the graphite-based material treated in Example 1 had a capacity of 364.69 mAh/g and an efficiency of 90.18%.

The method of the invention not only has the advantage of simple processing process, but it can be seen from Table 2 that the electrode anode material prepared by the method of the invention has the characteristics of high capacity and high efficiency.

Table 1 Process parameters of Examples 1-6 and Comparative Example 1

Example, comparative example	Speed rpm	Heating rate °C/min	Gas type	Flow rate m 3 /h	Maximum temperature °C	Hold time h	cooling method	Coated material	Coating process	Coating amount
Example 1	0	30	Oxygen and nitrogen	8	1000	2	Indirect cooling	Polypyrrole	Liquid phase	0.5%
Example 2	20	0.5	Bromine gas	0.05	310	4.5	Natural cooling	Polyacrylonitrile	Liquid phase	20%
Example 3	10	0.1	Air and nitrogen	5	500	1.0	Indirect cooling	asphalt	Solid Phase	8%
Example 4	3	80	Fluorine gas	1	100	0.5	Natural cooling	Polyethylene glycol	Liquid phase	15%
Example 5	13	100	Oxygen and argon	0.5	450	6	Indirect cooling	Acetylene	Gas phase	0%
Example 6	6	15	Chlorine gas	10	620	2.8	Indirect cooling	Methane	Gas phase	0.2%
Comparative example 1	no	no	no	no	no	no	Natural cooling	asphalt	Solid Phase	5%

Table 2 Electrical performance test results of Examples 1-6 and Comparative Example 1

Example, comparative example	Average particle size D50 um	Specific surface area m 2 /g	Capacity mAh/g	effectiveness %	Powder compaction density g/cm 3	45°C, 100-week capacity retention
Example 1	19.236	5.26	364.69	90.18	1.90	95%
Example 2	10.362	15.34	355.2	85.23	1.86	91%
Example 3	23.25	2.36	362.3	92.63	1.94	93.6%
Example 4	15.57	4.64	350.2	76.53	2.01	88%
Example 5	13.65	10.36	345.2	87.29	1.95	85%
Example 6	17.22	8.65	343.6	79.40	1.97	94.5%
Comparative example 1	18.23	3.56	355.6	89.6	1.67	92%

Claims (10)

1. An electrode negative electrode material comprising a matrix and a coating layer covering the same, wherein the substrate is a graphite material having a carbon content of 99.9% or more, and has a spherical shape and a length-to-minor axis ratio of 1.0 ～. 4.5 of more than one type of spherical block and sheet, the matrix contains nanopores or nanopores, the size of nanopores or nanopores is 10 to 500 nm, the porosity is 0.5 to 20%, and the true density is 2.0 to 2.26. g/cm ³ ; the coating layer is a non-graphite carbon material, the mass of the coating layer is greater than 0 to 20% of the mass of the matrix; the average particle size D ₅₀ of the composite material is 3.0 to 50.0 μm, and the specific surface area is 1.0. ~20.0 m ² /g, the composite material compact density is 1.50-2.15 g/cm ³ ; the graphite material is natural crystalline graphite, natural cryptocrystalline graphite, natural crystalline vein graphite, artificial graphite, carbon More than one type of microspheres and conductive graphite; the non-graphitic carbon material is soft carbon which is easy to graphitize, pyrolytic carbon or vapor deposited carbon; the soft carbon which is easy to graphitize is coal having a softening point of 30 to 300 ° C Asphalt, petroleum asphalt, coal tar, oil industry heavy oil and heavy One or more of the aromatic hydrocarbons; the organic substance is one of a high molecular polymer polyvinyl alcohol, polyvinyl chloride, polyethylene glycol, polyethylene oxide, polyvinylidene fluoride, acrylic resin, and polyacrylonitrile. The above or the polymer conductive polymer is at least one of polythiophene, polyaniline, polyacetylene, polypyrrole, polyacene, poly pheno, polyphenylene, polyphenylene vinyl, and polydiacetyl.
2. A method for preparing an electrode anode material comprises the steps of: first, oxidizing and/or reducing a graphite material, and heating the graphite material at a rate of 0.1 to 100 ° C/min, and at a flow rate of 0.05 to 10 m ³ /h; a mixture of an oxidation/reduction gas or an oxidation/reduction gas and an inert gas at a temperature of 100 to 1000 ° C; the graphite material is natural crystalline graphite, natural cryptocrystalline graphite, natural crystalline vein graphite, artificial graphite More than one type of carbon microspheres and conductive graphite; 2. Lowering temperature below 100 ° C, stopping the introduction of an oxidation/reduction gas or a mixed gas of an oxidizing/reducing gas and an inert gas; 3. Graphite after oxidation/reduction treatment The material is a graphite matrix, and the solid phase coating is easy to graphitize the soft carbon or the liquid phase coated organic pyrolytic carbon, and is pyrolyzed into a non-graphitic carbon material to obtain an electrode negative electrode material. The quality of the coating layer is greater than 0 to the mass of the graphite matrix. 20%; soft carbon which is easy to graphitize is one or more of coal tar pitch, petroleum tar pitch, coal tar, heavy oil of petroleum industry and heavy aromatic hydrocarbon having a softening point of 30 to 300 ° C; More than one of molecular polymer polyvinyl alcohol, polyvinyl chloride, polyethylene glycol, polyethylene oxide, polyvinylidene fluoride, acrylic resin and polyacrylonitrile, or polymer conductive polymer is polythiophene, poly More than one of aniline, polyacetylene, polypyrrole, polyacene, polyphage, polyphenylene, polyphenylene vinyl and polydiacetylene.
3. The method for preparing an electrode negative electrode material according to claim 2, wherein the electrode negative electrode material is heated to a temperature of 100 ° C or lower or vacuum dried to reduce the moisture content of the electrode negative electrode material to 0.1% or less.
4. The method for preparing an electrode negative electrode material according to claim 2, wherein the electrode negative electrode material is dried, sieved for demagnetization, demagnetized 1 to 20 times, magnetic induction intensity is 3000 to 30000 Gs, and the treatment temperature is 10 to 80 ° C, the electromagnetic hammer strike frequency is 3 to 180 times / sec, and then sieved to obtain an electrode negative electrode material having an average particle size D ₅₀ of 3.0 to 50.0 μm.
5. The method for producing an electrode negative electrode material according to claim 2, wherein in the oxidation/reduction treatment of the graphite-based material, the furnace chamber of the oxidized/reduced graphite-based material is rotated at a rotational speed of more than 0 to 20 rpm.
6. The method for preparing an electrode negative electrode material according to claim 2, wherein when the graphite material is oxidized/reduced, when the temperature reaches 100 to 1000 ° C, the heat retention is greater than 0 to 6 h.
7. The method for preparing an electrode negative electrode material according to claim 2, wherein the cooling is performed by introducing compressed air between the furnace wall and the heat conducting layer in the furnace wall or by naturally cooling the furnace.
8. The method for preparing an electrode negative electrode material according to claim 2, wherein the solid phase coated coating material is 1 to 20% of the mass of the graphite matrix, and the mixing speed is 100 to 500. r/min, mixed coating for 5 to 180 minutes, or fusion speed of 500 to 3000 r/min, the gap is 0.01-1.0 cm, the fusion temperature is 20-80 ° C, the fusion coating is 10-200 min, and the temperature is naturally lowered to room temperature.
9. The method for preparing an electrode negative electrode material according to claim 2, wherein the liquid phase coating comprises mixing the graphite substrate with a soluble organic substance having a mass of 0.1 to 20% of the graphite matrix, and is 2000 to 8000 r/min. Mixing at a speed of 10 to 120 minutes, the solvent for liquid phase mixing is water or an organic solvent, the mass of the solvent is 0.8 to 2.0 times the mass of the graphite matrix, the mixing temperature is 10 to 90 ° C, and the drying is performed at 80 to 300 ° C. Dry treatment for 1-30h.
10. A method for preparing an electrode anode material comprises the steps of: first, oxidizing and/or reducing a graphite material, and heating the graphite material at a rate of 0.1 to 100 ° C/min, and at a flow rate of 0.05 to 10 m ³ /h; An oxygen/reduction gas or a mixed gas of an oxidizing/reducing gas and an inert gas is introduced, the temperature is 100-1000 ° C, and the heat is maintained for more than 0 to 6 h; 2. The gas phase coating is carried out, and a carbon-containing gas is introduced, and the amount of the gas is 0.05. -15m ³ /h, after 0.1-5h, the furnace is cooled to below 100 °C, and the mixed gas of oxidation/reduction gas or oxidation/reduction gas and inert gas is stopped; the carbonaceous gas is methane, acetylene, One or more of ethylene, CO ₂ , natural gas, liquefied petroleum gas, benzene, and thiophene.

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