CN113161518A - Lithium ion secondary battery cathode, preparation method thereof and lithium ion secondary battery - Google Patents

Lithium ion secondary battery cathode, preparation method thereof and lithium ion secondary battery Download PDF

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CN113161518A
CN113161518A CN202010014686.5A CN202010014686A CN113161518A CN 113161518 A CN113161518 A CN 113161518A CN 202010014686 A CN202010014686 A CN 202010014686A CN 113161518 A CN113161518 A CN 113161518A
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secondary battery
ion secondary
lithium ion
negative electrode
cobalt
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洪晔
胡倩倩
董海勇
吴春宇
长世勇
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Guangzhou Automobile Group Co Ltd
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/139—Processes of manufacture
    • H01M4/1397—Processes of manufacture of electrodes based on inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy
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    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
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    • H01M4/00—Electrodes
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    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
    • H01M4/581—Chalcogenides or intercalation compounds thereof
    • H01M4/5815—Sulfides
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
    • H01M4/583—Carbonaceous material, e.g. graphite-intercalation compounds or CFx
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    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
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Abstract

The invention provides a lithium ion secondary battery cathode, a preparation method thereof and a lithium ion secondary battery cathode. The lithium ion secondary battery cathode consists of three parts: the copper-doped carbon nano-particle comprises a copper current collector, nine cobalt octasulfide nano-particles loaded on the copper current collector and a nitrogen-doped carbon thin layer wrapped on the surfaces of the nine cobalt octasulfide nano-particles. The preparation process of the cathode realizes the organic combination of composite material synthesis and electrode preparation, and the cobalt octasulfide nonacobalt/carbon compound is obtained through the synchronous heat treatment of a cobalt disulfide template and polyacrylonitrile on a copper foil. The cathode effectively improves the conductivity of the composite electrode by utilizing the synergistic effect of the nano-scale cobalt octasulfide nanoparticles and the carbon coating layer, can relieve the volume expansion of the cobalt octasulfide nanoparticles in circulation, and can realize high specific capacity and excellent cycle performance when applied to a lithium ion secondary battery.

Description

Lithium ion secondary battery cathode, preparation method thereof and lithium ion secondary battery
Technical Field
The invention is applied to the field of lithium ion secondary batteries, and particularly relates to a battery cathode, a preparation method thereof and a lithium ion secondary battery.
Background
The negative electrode of a lithium ion secondary battery is an important component of the battery, and the structure and the performance of the negative electrode directly influence the capacity and the cycle performance of the battery. At present, most of commercial lithium ion secondary batteries adopt graphite materials as negative electrodes, the theoretical specific capacity is only 372mAh/g, and the development requirements of the lithium ion secondary batteries are difficult to meet. Cobalt sulfide (CoS )2、Co3S4、Co9S8Etc.) has the advantages of high specific capacity, high conductivity, good thermal stability, etc., and is considered to be a potential negative electrode material for lithium ion secondary batteries. However, cobalt sulfide is accompanied by huge volume expansion during cycling, easily causes electrode pulverization and shedding, and has low battery gram capacity and poor cycling stability. The design of composite structures for cobalt sulfide materials is considered to be one of the main approaches to improving their electrochemical performance.
The invention patent CN109360973A 'a preparation method of cobalt sulfide/three-dimensional nitrogen-doped macroporous graphene and a lithium ion secondary battery cathode material' discloses a CoS/three-dimensional graphene composite material, wherein CoS is uniformly loaded on the holes and the surface of the three-dimensional macroporous graphene. However, cobalt sulfide is directly exposed in the electrolyte in the circulation process, side reaction is easy to occur with the electrolyte, and repeated volume expansion in the circulation process easily causes the cobalt sulfide particles to fall off and lose activity. In addition, the graphene is adopted as the composite material, so that the cost is high and the synthesis process is complex.
The invention patent CN108017094A 'a hexagonal cobalt sulfide/carbon composite material and a preparation method thereof' discloses a hexagonal cobalt sulfide micron sheet, wherein the surface of the micron sheet is coated with a carbon layer. The composite material is synthesized by a method of calcining a hexagonal Co-Al LDHs/polydopamine composite material and sublimed sulfur powder at high temperature. The cobalt sulfide is prepared by a high-temperature calcination method, and polydopamine is used as a carbon coating source, so that the cost is high, and the synthesis process is complex.
In addition, the composite material synthesized by the prior art needs to be mixed with a certain amount of binder to form slurry subsequently, and the slurry is coated on a copper foil to manufacture a negative plate, so that the process is complicated, and the introduced non-conductive binder (such as polyvinylidene fluoride (PVDF) and the like) is not beneficial to improving the overall conductivity of the electrode.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: aiming at the defects that the pole piece pulverization is caused by the volume expansion of cobalt sulfide as a negative active material in the charging and discharging processes, the cost is high, the synthesis process is complex and the like which are not beneficial to the overall electrical performance of the battery in the prior art, the negative electrode of the lithium ion secondary battery with a new structure is provided, the cost of the negative electrode is low, the process is simple, and the comprehensive electrical performance of the battery can be improved.
In order to solve the technical problem, the invention provides a lithium ion secondary battery cathode, which comprises a current collector and a cathode material loaded on the current collector, wherein the cathode material comprises cobalt nonaoctasulfide (Co)9S8) And the surface of the cobalt nonaoctasulfide nano-particles is coated with a nitrogen-doped carbon layer.
Optionally, the particle size of the cobalt nonaoctasulfide nanoparticles is 50-500 nm, more preferably 100-300 nm, and the thickness of the nitrogen-doped carbon layer is 1-40 nm, more preferably 3-15 nm.
In order to solve the technical problem, the invention also provides a preparation method of the lithium ion secondary battery cathode, which comprises the following steps:
(1) adding cobalt disulfide powder and polyacrylonitrile powder into an organic solvent, and stirring and mixing to obtain slurry;
(2) coating the slurry on a current collector and drying to obtain a negative electrode coated with cobalt disulfide and polyacrylonitrile;
(3) and carrying out heat treatment on the cathode in an inert atmosphere, wherein the heat treatment enables cobalt disulfide to react to generate nonacobalt octasulfide nanoparticles, and meanwhile, the polyacrylonitrile is pyrolyzed to form a nitrogen-doped carbon layer coating the nonacobalt octasulfide nanoparticles.
Optionally, in the step (1), the mass ratio of the cobalt disulfide to the polyacrylonitrile is 95: 5-60: 40.
optionally, the organic solvent in step (1) is dimethylformamide or dimethylacetamide.
Optionally, the drying temperature in the step (2) is 60-100 ℃.
Optionally, in the step (3), the temperature is raised to a specific temperature at a rate of 2-10 ℃/min, and then the temperature is kept constant, wherein the specific temperature is 350-650 ℃, more preferably 400-.
The invention also provides a secondary battery which comprises a positive electrode, a negative electrode and electrolyte, wherein the negative electrode comprises the negative electrode of the lithium ion secondary battery or the negative electrode of the lithium ion secondary battery prepared by the preparation method of the negative electrode of the lithium ion secondary battery.
Compared with the prior art, the lithium ion secondary battery cathode provided by the invention has the beneficial effects that the active material of the cathode is nonacobalt octasulfide (Co)9S8) The surface of the nano-particles is coated with a nitrogen-doped carbon layer structure, so that the electrochemical performance of the composite cathode is obviously improved. Co9S8Has the advantages of high specific capacity, high conductivity, good thermal stability and the like, and adopts nanoscale Co9S8Particles of Co as small as possible9S8Volume changes during charging and discharging; co9S8The nanoparticles and the nitrogen-doped carbon coating have a synergistic effect, the carbon layer being not only Co9S8Electron transport channels between the particles, also Co9S8The electron transmission channel between the particles and the current collector ensures that the overall conductivity of the electrode can still reach a better level under the condition of not additionally adding a conductive agent; theCoating of nitrogen-doped carbon layer on Co9S8The protective layer is formed on the surface of the particles, so that the side reaction between the particles and the electrolyte is inhibited, and high specific capacity and excellent cycle performance can be realized. In addition, the invention simplifies the preparation process and realizes the organic combination of composite material synthesis and electrode preparation. In the preparation stage of the pole piece, CoS is added2Coating the mixture with polyacrylonitrile on a copper current collector, CoS2As Co9S8The polyacrylonitrile is simultaneously used as a binder for preparing the electrode and an organic carbon source of nitrogen-doped carbon. In the heat treatment stage, Co is synchronously realized9S8The obtained pole piece can be directly applied to subsequent battery assembly by synthesizing the particles and the nitrogen-doped carbon coating, and the electrode preparation process is greatly simplified. In addition, the preparation method disclosed by the invention realizes organic combination of composite material synthesis and electrode preparation, and the used raw materials are all commercial materials, so that the preparation method has the advantages of low cost, simple process, strong controllability and the like, and has a large-scale industrial application prospect.
Drawings
Fig. 1 is a schematic view of the structure of a negative electrode of a lithium ion secondary battery according to an embodiment of the present invention.
FIG. 2 shows Co in an embodiment of the present invention9S8Schematic structure of the/C complex.
FIG. 3 is a diagram of a commercially available CoS used in example 1 of the present invention2XRD pattern of powder.
FIG. 4 is a diagram of commercially available CoS used in example 1 of the present invention2SEM photograph of the powder.
Fig. 5 is an XRD spectrum of the negative electrode prepared in example 1 of the present invention.
FIG. 6 shows Co in the negative electrode prepared in example 1 of the present invention9S8SEM photograph of/C complex.
FIG. 7 shows Co in the negative electrode prepared in example 1 of the present invention9S8TEM image of the/C complex.
Fig. 8 is a graph showing cycle characteristics of the negative electrodes prepared in example 1 of the present invention and comparative example 1 at a current density of 0.1A/g.
Fig. 9 is a graph of the cycle performance of the negative electrode prepared in example 1 of the present invention at different current densities.
Wherein, in FIG. 1, reference numeral 1 is Cu foil, and 2 is Co9S8a/C complex. Reference numeral 21 in FIG. 2 denotes Co9S8Particle, 22, is a nitrogen doped carbon coating.
Detailed Description
In order to make the technical problems, technical solutions and advantageous effects solved by the present invention more clearly apparent, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
The invention provides a lithium ion secondary battery cathode, which comprises a current collector and a cathode material loaded on the current collector, wherein the cathode material comprises nine cobalt octasulfide (Co)9S8) And the surface of the cobalt nonaoctasulfide nano-particles is coated with a nitrogen-doped carbon layer. Co9S8Has the advantages of high specific capacity, high conductivity, good thermal stability and the like, and adopts nanoscale Co9S8Particles of Co as small as possible9S8Volume changes during charging and discharging; co9S8The nanoparticles and the nitrogen-doped carbon coating have a synergistic effect, the carbon coating being not only Co9S8Electron transport channels between the particles, also Co9S8The electron transmission channel between the particles and the current collector ensures that the overall conductivity of the electrode can still reach a better level under the condition of not additionally adding a conductive agent; the nitrogen-doped carbon layer is coated on Co9S8The protective layer is formed on the surface of the particles, so that the side reaction between the particles and the electrolyte is inhibited, and high specific capacity and excellent cycle performance can be realized.
In one embodiment of the present invention, the particle size of the cobalt nonaoctasulfide nanoparticles is 50 to 500nm, preferably 100 to 300nm, and the thickness of the nitrogen-doped carbon layer is 1 to 40nm, preferably 3 to 15 nm. The nitrogen-doped carbon coating layer in the range can increase the overall conductivity of the compound, does not cause great obstruction to the transport of lithium ions, and is more beneficial to the overall performance of the electrochemical performance of the compound.
In a specific embodiment of the invention, the current collector may be a negative current collector conventional in the art, such as a copper foil, with a thickness of 8-20 μm, preferably 16 μm.
As one embodiment of the present invention, the present invention provides a method for preparing a negative electrode material for a lithium ion secondary battery, comprising the steps of: (1) adding cobalt disulfide powder and polyacrylonitrile powder into an organic solvent, and stirring and mixing to obtain slurry; (2) coating the slurry on a current collector and drying to obtain a negative electrode coated with cobalt disulfide and polyacrylonitrile; (3) and carrying out heat treatment on the cathode in an inert atmosphere, wherein the heat treatment enables cobalt disulfide to react to generate nonacobalt octasulfide nanoparticles, and meanwhile, the polyacrylonitrile is pyrolyzed to form a nitrogen-doped carbon layer coating the nonacobalt octasulfide nanoparticles.
As one of the specific embodiments of the invention, the mass ratio of the cobalt disulfide to the polyacrylonitrile in the step (1) is 95: 5-60: 40; the preferable mass ratio is 90: 10-70: 30; the organic solvent is dimethylformamide or dimethylacetamide. In the step (2), the drying temperature is 60-100 ℃.
As one embodiment of the invention, commercial cobalt disulfide (CoS) is weighed according to a specific mass ratio2) Adding the powder and commercial polyacrylonitrile powder into a dimethylformamide solvent, stirring to prepare slurry with good fluidity, carrying out doctor-blade casting on a copper foil to form a uniform thin layer, and drying at 60-100 ℃ to obtain the cobalt disulfide/polyacrylonitrile composite negative electrode. In the process, polyacrylonitrile is used as a binder at the same time, so that good bonding between cobalt disulfide particles and between cobalt disulfide and copper foil is realized.
As one embodiment of the invention, a step of cutting the negative electrode obtained in the step (2) is further included between the step (2) and the step (3), and then the heat treatment in the step (3) is carried out on the cut negative electrode piece.
As one embodiment of the present invention, step (3)The heat treatment is carried out in an inert atmosphere, wherein the inert atmosphere can be any one of nitrogen or argon, the cobalt disulfide/polyacrylonitrile composite negative electrode is placed into a tube furnace, the temperature is raised to a specific temperature at the speed of 2-10 ℃/min, then the temperature is kept, the specific temperature is 350-650 ℃, more preferably 400-500 ℃, and the constant temperature time is 5-60 min. In this temperature range, CoS2Decomposition to Co9S8And polyacrylonitrile can be completely carbonized. Below this temperature range, polyacrylonitrile is not completely carbonized, above this temperature, sample mass changes greatly before and after heat treatment, resulting in loose material structure, easy fall-off of active substances from copper foil, and is not favorable for maintaining the overall stability of electrode structure.
As one embodiment of the present invention, there is provided a lithium ion secondary battery comprising a positive electrode, a negative electrode and an electrolyte, wherein the negative electrode comprises the above-described lithium ion secondary battery negative electrode, or a lithium ion secondary battery negative electrode prepared by the above-described method for preparing a lithium ion secondary battery negative electrode.
The positive electrode and the electrolyte are not particularly limited, and conventional positive electrodes and electrolytes of lithium ion secondary batteries can be selected and obtained by conventional technical means or commercial purchase in the field, belong to the known technology in the field, and are not described again.
The present invention will be described in further detail with reference to examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Example 1
The embodiment provides a lithium ion secondary battery cathode, the structure of which comprises a copper foil and Co uniformly distributed on the copper foil9S8the/C complex, as shown in FIG. 1. The thickness of the copper foil was 16 μm. Co9S8the/C complex is made of Co9S8The particles and the carbon coating layer are composed together as shown in fig. 2. Co9S8The particle size of the particles is 100-300 nm. Is uniformly wrapped in Co9S8A nitrogen-doped carbon layer on the surface of the particles, the thickness of the nitrogen-doped carbon layer is about 5-15 nm, and C is realized by the carbon layero9S8Good electrical contact between the particles and the copper foil.
The embodiment also provides a preparation method of the lithium ion secondary battery cathode, which comprises the following steps:
weighing cobalt disulfide (CoS) according to the mass ratio of 8:22) Adding the powder and polyacrylonitrile powder into a dimethylformamide solvent, stirring to prepare slurry with good fluidity, carrying out doctor blade casting on a copper foil to form a uniform thin layer, and drying at 80 ℃ to obtain the cobalt disulfide/polyacrylonitrile composite negative electrode. Cutting the prepared cobalt disulfide/polyacrylonitrile composite negative electrode into small round pieces with the diameter of 12mm, putting the small round pieces into a tubular furnace, heating the small round pieces to 400 ℃ at the speed of 5 DEG/min in the nitrogen atmosphere, and carbonizing the small round pieces at constant temperature for 10min to obtain Co9S8a/C composite negative electrode.
Characterization of commercial CoS Using multiple test methods2Powder and Co9S8The phase and morphology of the/C composite negative electrode are shown in FIGS. 3-7. XRD pattern (FIG. 3) shows commercial CoS2The powder is single CoS2Crystalline phase, no other impurities present. As can be seen from the SEM image (FIG. 4), commercial CoS2The powder is granular in shape, the particle size is 100-300 nm, and larger clusters are formed by stacking. The XRD pattern (fig. 5) shows that the composite negative electrode comprises copper foil (Cu) and nonacobalt octasulfide (Co)9S8) In addition, there are some minor impurity peaks corresponding to Cu2And the S phase is a byproduct of the reaction of S steam generated in the heat treatment process and the copper foil. As can be seen from the SEM image (FIG. 6), Co9S8The particle size of the particles is about 100-300 nm, and the morphology is similar to that of the originally adopted CoS2Substantially consistent. As can be seen from the TEM image (FIG. 7), Co9S8The outer layer of the particles is distributed with a carbon coating thin layer, and the thickness is about 5-15 nm. The above characterization results show that the nanoscale Co can be synthesized by the above preparation method by using commercial raw materials9S8Particles of and Co9S8The surface of the particle is distributed with a nitrogen-doped carbon coating layer with high conductivity.
Co prepared in example 19S8Application of/C composite cathode to lithium ionThe secondary battery exhibits excellent electrochemical properties. The first discharge specific capacity and the second discharge specific capacity of the composite cathode under the current density of 0.1A/g are 1253mAh/g and 1060mAh/g respectively, the specific capacity is stabilized at 1015mAh/g after 25 times of circulation, and the specific capacity retention rate of the composite cathode and the second discharge specific capacity reaches 95.7% (figure 8). Fig. 9 is a graph of cycling performance of the composite negative electrode at different current densities. The figure shows that the composite negative electrode can provide higher specific capacity when circulating under different current densities, and can still be stably tested after high-current charging and discharging, and the composite negative electrode shows excellent circulating stability.
To illustrate the advantages of the composite electrode structure design of the present invention, the inventors also conducted the following comparative experiments: comparative example 1
The present comparative example differs structurally from example 1 in that the final electrode is composed of copper foil and cobalt disulfide/polyacrylonitrile composite. Wherein, the surface of the cobalt disulfide particles is distributed with a polyacrylonitrile coating layer which is not carbonized.
The preparation method is different from the example 1 in that the heat treatment is not continued after the preparation of the cobalt disulfide/polyacrylonitrile composite electrode. The other process steps are the same as in example 1. The cycle performance of the composite anode at 0.1A/g is shown in FIG. 8. As can be seen from the figure, the first discharge specific capacity of the composite negative electrode is 491mAh/g, but the 2 nd discharge specific capacity is attenuated to 34 mAh/g. The reason is that polyacrylonitrile is not carbonized, a nitrogen-doped carbon coating layer with high conductivity cannot be formed, the whole conductivity of the electrode is poor, and the specific capacity of active substances is rapidly attenuated.
Co prepared according to the invention, compared to the comparative examples described above9S8the/C composite negative electrode can realize higher specific capacity and more excellent cycle performance, which is caused by Co9S8The nitrogen-doped carbon coating thin layer on the surface of the particle is beneficial to inhibiting Co9S8And the side reaction with the electrolyte improves the overall conductivity of the electrode, and greatly contributes to the improvement of the capacity of the composite cathode.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims (10)

1. The lithium ion secondary battery negative electrode comprises a current collector and a negative electrode material loaded on the current collector, and is characterized in that the negative electrode material comprises nine cobalt octasulfide nanoparticles, and the surfaces of the nine cobalt octasulfide nanoparticles are coated with nitrogen-doped carbon layers.
2. The negative electrode for a lithium ion secondary battery according to claim 1, wherein the particle size of the nonacobalt octasulfide nanoparticles is 50 to 500nm, and the thickness of the nitrogen-doped carbon layer is 1 to 40 nm.
3. The negative electrode for a lithium ion secondary battery according to claim 2, wherein the particle size of the nonacobalt octasulfide nanoparticles is 100 to 300nm, and the thickness of the nitrogen-doped carbon layer is 3 to 15 nm.
4. A preparation method of a lithium ion secondary battery cathode is characterized by comprising the following steps:
(1) adding cobalt disulfide powder and polyacrylonitrile powder into an organic solvent, and stirring and mixing to obtain slurry;
(2) coating the slurry on a current collector and drying to obtain a negative electrode coated with cobalt disulfide and polyacrylonitrile;
(3) and carrying out heat treatment on the cathode in an inert atmosphere, wherein the heat treatment enables cobalt disulfide to react to generate nonacobalt octasulfide nanoparticles, and meanwhile, the polyacrylonitrile is pyrolyzed to form a nitrogen-doped carbon layer coating the nonacobalt octasulfide nanoparticles.
5. The method for preparing the negative electrode of the lithium-ion secondary battery according to claim 4, wherein the mass ratio of the cobalt disulfide to the polyacrylonitrile in the step (1) is 95: 5-60: 40.
6. the method of manufacturing a negative electrode for a lithium ion secondary battery according to claim 4, wherein the organic solvent in the step (1) is dimethylformamide or dimethylacetamide.
7. The method for preparing a negative electrode for a lithium ion secondary battery according to claim 4, wherein the drying temperature in the step (2) is 60 to 100 ℃.
8. The method for preparing the negative electrode of the lithium ion secondary battery according to claim 4, wherein the heat treatment in the step (3) is performed by raising the temperature to a specific temperature at a rate of 2-10 ℃/min, and then keeping the temperature, wherein the specific temperature is 350-650 ℃, and the constant temperature time is 5-60 min.
9. The method for preparing a negative electrode for a lithium ion secondary battery according to claim 8, wherein the specific temperature is 400-500 ℃.
10. A lithium ion secondary battery comprising a positive electrode, a negative electrode and an electrolytic solution, characterized in that the negative electrode comprises the negative electrode for a lithium ion secondary battery according to any one of claims 1 to 3, or the negative electrode for a lithium ion secondary battery produced by the method for producing the negative electrode for a lithium ion secondary battery according to any one of claims 4 to 9.
CN202010014686.5A 2020-01-07 2020-01-07 Lithium ion secondary battery cathode, preparation method thereof and lithium ion secondary battery Pending CN113161518A (en)

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