A lithium-ion battery anode, its preparation method and applications

Abstract

This invention provides a lithium-ion battery anode, its preparation method, and its uses. The lithium-ion battery anode includes a current collector and a slurry film coating the current collector. The slurry film includes an N-type conductive organic material. The N-type conductive organic material includes any one or a combination of at least two of polyaniline, polyaniline derivatives, perylene tetrahydric anhydride, perylene tetrahydric anhydride derivatives, aromatic diimides, or aromatic diimide derivatives. By coating the current collector with a slurry containing mixed N-type conductive organic materials, the N-type conductive organic material is added to the lithium-ion battery anode, which can improve the fast charging capability of the lithium-ion battery, accelerate the diffusion of lithium ions to the anode, reduce concentration polarization, and effectively improve the charging speed of the lithium-ion battery.

Description

Technical Field

[0001] This invention relates to the field of lithium-ion battery technology, and in particular to a lithium-ion battery anode, its preparation method, and its applications. Background Technology

[0002] With the development of mobile electronic devices and electric vehicles, the charging speed of lithium-ion batteries has become increasingly important. Improving the fast-charging capability of lithium-ion batteries requires ensuring a rapid diffusion rate of lithium ions within the electrode. The diffusion rate of lithium ions within the electrode is affected by the electrode's formulation, pore structure, and thickness. Therefore, the lithium battery industry typically focuses on improving these three aspects. Reducing electrode thickness is an effective method to improve the fast-charging performance of the cell, but it inevitably leads to a decrease in battery energy density. The electrode pore structure can be improved by adding pore-forming agents and through physical pore creation. However, pore-forming agents are prone to remaining in the electrode, harming battery performance, while physical pore creation methods generate dust, posing a safety hazard. Multilayer coating methods can achieve optimized pore distribution within the electrode, but the process is more complex and increases costs. Furthermore, the formulation of conductive agents and binders also affects lithium-ion transport, but there is limited room for further optimization and improvement.

[0003] CN110148708A discloses a negative electrode sheet and a lithium-ion battery. The negative electrode sheet includes a negative electrode current collector and a film layer coated on the negative electrode current collector. The film layer consists of two layers: a first coating layer is a bottom graphite coating close to the negative electrode current collector; and a second coating layer is a top silicon-containing coating away from the copper foil. A double-layer coating technique is used, in which two slurries are simultaneously coated onto the negative electrode current collector. After forming a double-layer paste structure on the same side of the negative electrode current collector, a double-layer coated negative electrode sheet is obtained with a silicon-containing coating on the top layer and a silicon-free pure graphite layer on the bottom layer. However, the structure and preparation method of the negative electrode sheet are relatively complex.

[0004] CN106941167A discloses a porous composite anode material for lithium-ion batteries and its preparation method. The preparation method includes the following steps: mixing porous graphite material, conductive agent, polymer, and pore-forming agent uniformly in a solvent to obtain an electrospinning solution; electrospinning the electrospinning solution to obtain composite fibers; under inert gas protection, first keeping the composite fibers at 300℃ for 1 hour, then calcining them at a temperature range of 1000-1500℃ for 0.5-15 hours, and then cooling to room temperature to obtain the final product; or first keeping the composite fibers at 300-320℃ for 1-2 hours, then calcining them at 1000-1500℃ for 0.5-15 hours, cooling, adding a chemical etchant to remove the pore-forming agent, drying, and then cooling to obtain the final product. However, the preparation method of the anode material is relatively complex.

[0005] CN112864351A discloses a negative electrode and a lithium secondary battery containing the negative electrode. The negative electrode includes a current collector, a first negative electrode active material layer, and a second negative electrode active material layer. The first negative electrode active material layer is formed on at least one surface of the current collector and includes a mixture of natural graphite and artificial graphite as negative electrode active materials and a first binder. The second negative electrode active material layer is formed on the first negative electrode active material layer and includes a phosphorus-carbon composite as a negative electrode active material and a second binder. However, the structure and preparation method of the negative electrode sheet are relatively complex.

[0006] Therefore, it is necessary to develop a lithium-ion battery anode with a simple structure, a simple preparation method, and the ability to effectively improve the charging speed of lithium-ion batteries. Summary of the Invention

[0007] To address the aforementioned technical problems, this invention provides a lithium-ion battery anode, its preparation method, and its applications. The lithium-ion battery anode includes a current collector and a slurry film coating the current collector. The slurry film includes an N-type conductive organic material. This invention, through a preparation method that mixes the N-type conductive organic material, the anode material itself, a conductive agent, a binder, and a solvent, and then coats it onto the current collector, adds the N-type conductive organic material to the lithium-ion battery anode. This enhances the fast-charging capability of the lithium-ion battery. When applied to lithium-ion batteries, the electron-rich groups in the N-type conductive organic material can strongly adsorb lithium ions in the electrolyte, accelerating the diffusion of lithium ions to the anode, reducing concentration polarization, and effectively improving the charging speed of the lithium-ion battery.

[0008] To achieve this objective, the present invention adopts the following technical solution:

[0009] In a first aspect, the present invention provides a lithium-ion battery negative electrode, the lithium-ion battery negative electrode comprising a current collector and a slurry film coating the current collector; the slurry film comprising an N-type conductive organic material; the N-type conductive organic material comprising any one or a combination of at least two of polyaniline, polyaniline derivatives, perylene tetrahydric anhydride, perylene tetrahydric anhydride derivatives, aromatic diimides, or aromatic diimide derivatives, wherein typical but non-limiting combinations are: a combination of polyaniline and polyaniline derivatives, a combination of perylene tetrahydric anhydride and perylene tetrahydric anhydride derivatives, a combination of aromatic diimides and aromatic diimide derivatives, or a combination of polyaniline, perylene tetrahydric anhydride, and aromatic diimides, etc.

[0010] Among them, N-type conductive organics refer to conductive organics with electron-rich groups, including halogen atoms, nitrogen atoms, hydroxyl groups, carbonyl groups, cyano groups, amino groups, ester groups, aminoacyl groups, amide groups, or aminoacyl groups.

[0011] This invention effectively enhances the fast-charging capability of lithium-ion batteries by adding an N-type conductive polymer to the negative electrode. The electron-rich groups in the N-type conductive polymer contain lone pairs of electrons, which can generate a strong electrostatic adsorption effect on lithium ions in the electrolyte. During fast charging, lithium ions diffuse from the positive electrode to the negative electrode, and the lithium ion concentration in the electrolyte in the positive electrode region is higher than that in the negative electrode region. The adsorption effect of the N-type conductive polymer on lithium ions can accelerate this diffusion process and increase the lithium ion concentration in the electrolyte in the negative electrode region. Therefore, concentration polarization can be reduced, and the fast-charging performance of the battery can be improved.

[0012] Preferably, the polyaniline derivative includes polydiphenylamine, polytriphenylamine, a polymeric organic compound with polydiphenylamine as the main structure, or a polymeric organic compound with polytriphenylamine as the main structure.

[0013] Preferably, the perylene tetrahydric anhydride derivative comprises a high molecular weight organic compound with perylene tetrahydric anhydride as the main structure.

[0014] Preferably, the aromatic diimide derivative includes naphthalimide, perylene diimide, a high molecular weight organic compound with naphthalimide as the main structure, or a high molecular weight organic compound with perylene diimide as the main structure.

[0015] Preferably, the slurry membrane further includes a negative electrode material, a conductive agent, and a binder.

[0016] Preferably, the negative electrode material includes any one or a combination of at least two of natural graphite, artificial graphite, hard carbon, silicon, or silicon suboxide. Typical but non-limiting combinations include: a combination of natural graphite and artificial graphite, a combination of artificial graphite and hard carbon, a combination of hard carbon and silicon, silicon and silicon suboxide, or a combination of hard carbon, silicon, and silicon suboxide, etc.

[0017] Preferably, the conductive agent comprises any one or a combination of at least two of carbon black, graphite, or carbon nanotubes, wherein typical but non-limiting combinations include: a combination of carbon black and graphite, a combination of graphite and carbon nanotubes, a combination of carbon black and carbon nanotubes, or a combination of carbon black, graphite, and carbon nanotubes, etc.

[0018] Preferably, the adhesive comprises any one or a combination of at least two of sodium carboxymethyl cellulose, lithium carboxymethyl cellulose, styrene-butadiene rubber, polyvinylidene fluoride, or polymethyl methacrylate, wherein typical but non-limiting combinations are: a combination of sodium carboxymethyl cellulose and lithium carboxymethyl cellulose, a combination of lithium carboxymethyl cellulose and styrene-butadiene rubber, a combination of polyvinylidene fluoride and polymethyl methacrylate, or a combination of styrene-butadiene rubber, polyvinylidene fluoride, and polymethyl methacrylate.

[0019] Preferably, the mass ratio of the negative electrode material, conductive agent, and binder is (90-98):(1-3):(1-3), for example, it can be 90:1:1, 90:1:2, 90:1:3, 95:1:1, 95:1:2, 95:1:3, 98:1:1, 98:1:2, 98:1:3, 90:1:1, 95:2:1, or 98:3:1, etc.

[0020] Preferably, the amount of the N-type conductive organic material added accounts for 0.5 to 5 wt% of the weight of the slurry film, for example, it can be 0.5 wt%, 1 wt%, 1.5 wt%, 2 wt%, 2.5 wt%, 3 wt%, 3.5 wt%, 4 wt%, 4.5 wt%, or 5 wt%.

[0021] The present invention further optimizes the addition of N-type conductive organic matter within the above-mentioned range, which is more conducive to improving the fast charging performance and maximum lithium plating rate of the battery.

[0022] Preferably, the secondary particles D50 of the N-type conductive organic material have a particle size ≤20μm, such as 20μm, 19μm, 18μm, 17μm, 16μm, 15μm, 14μm, 13μm, 12μm, 11μm or 10μm, etc.

[0023] The control of the secondary particle D50 of the N-type conductive organic material described in this invention has a significant impact on the performance of the final negative electrode material. Controlling D50 within the above-mentioned range is more conducive to reducing liquid phase resistance.

[0024] Preferably, the thickness of the slurry film is 50 to 150 μm, for example, it can be 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm or 150 μm.

[0025] The present invention preferably controls the thickness of the slurry film within the above-mentioned range, which can further improve fast charging performance and maximum lithium plating rate while ensuring battery stability.

[0026] In a second aspect, the present invention provides a method for preparing the lithium-ion battery negative electrode described in the first aspect, the method comprising the following steps:

[0027] (1) Mix N-type conductive organic material, negative electrode material, conductive agent, binder and solvent to obtain slurry, wherein the N-type conductive organic material includes any one or a combination of at least two of polyaniline, polyaniline derivative, perylene tetrahydric anhydride, perylene tetrahydric anhydride derivative, aromatic diimide or aromatic diimide derivative.

[0028] (2) The slurry described in step (1) is coated onto the current collector and dried to form a slurry film, thereby obtaining the negative electrode of the lithium-ion battery.

[0029] The method for preparing the negative electrode of a lithium-ion battery of the present invention involves mixing an N-type conductive organic material, a negative electrode main material, a conductive agent, a binder, and a solvent, and then coating the resulting slurry onto a current collector. The preparation method is simple and convenient, does not require modification of existing lithium battery production lines, and has the advantages of easy implementation, low cost, and significant improvement in fast charging performance.

[0030] In this invention, the addition of N-type conductive organic materials is not limited to liquid-phase mixing; other electrode fabrication methods, such as dry electrode processes, can also achieve the same purpose. Any lithium-ion anode containing N-type conductive organic powder particles can be used.

[0031] Preferably, the solvent in step (1) comprises water and / or N-methylpyrrolidone.

[0032] Preferably, the amount of solvent added in step (1) accounts for 40 to 60 wt% of the slurry by weight, for example, it can be 40 wt%, 42 wt%, 44 wt%, 46 wt%, 48 wt%, 50 wt%, 52 wt%, 54 wt%, 56 wt%, 58 wt%, or 60 wt%.

[0033] Thirdly, the present invention provides the use of the lithium-ion battery negative electrode as described in the first aspect in a lithium-ion battery.

[0034] When the lithium-ion battery negative electrode described in this invention is applied to a lithium-ion battery, the electron-rich groups in the N-type conductive organic material can strongly adsorb lithium ions in the electrolyte, which can accelerate the diffusion of lithium ions to the negative electrode, reduce concentration polarization, and effectively improve the charging speed of the lithium-ion battery.

[0035] Compared with the prior art, the present invention has at least the following beneficial effects:

[0036] (1) The present invention provides a lithium-ion battery negative electrode, wherein the lithium-ion battery negative electrode includes a current collector and a slurry film covering the current collector; the slurry film includes N-type conductive organic material, wherein the electron-rich groups in the N-type conductive organic material can strongly adsorb lithium ions in the electrolyte, thereby accelerating the diffusion of lithium ions to the negative electrode, reducing concentration polarization, effectively improving the charging speed of the lithium-ion battery, and the liquid phase resistance of the lithium-ion battery negative electrode is small, preferably below 5.3mΩ, with good fast charging performance and a maximum lithium plating rate preferably above 3.8C;

[0037] (2) The present invention provides a method for preparing a lithium-ion battery negative electrode by mixing N-type conductive organic matter, negative electrode main material, conductive agent, binder and solvent, and coating the obtained slurry onto the current collector. The preparation method is simple and convenient, does not require modification of existing lithium battery production lines, and has the advantages of easy implementation, low cost and significant improvement in fast charging performance. Detailed Implementation

[0038] To facilitate understanding of the present invention, the following embodiments are provided. Those skilled in the art should understand that these embodiments are merely illustrative and should not be construed as limiting the scope of the invention.

[0039] I. Implementation Examples

[0040] Example 1

[0041] This embodiment provides a lithium-ion battery negative electrode, which includes a current collector and a slurry film coating the current collector. The slurry film includes an N-type conductive organic material. The N-type conductive organic material includes polyaniline (molecular weight 2000) and polydiphenylamine (molecular weight 3000) in a mass ratio of 1:1. The slurry film also includes a negative electrode main material, a conductive agent, and a binder. The negative electrode main material is natural graphite, the conductive agent is carbon black, and the binder is sodium carboxymethyl cellulose. The mass ratio of the negative electrode main material, the conductive agent, and the binder is 95:2:3. The amount of N-type conductive organic material added accounts for 3 wt% of the weight of the slurry film. The secondary particle D50 particle size of the N-type conductive organic material is 15 μm, and the thickness of the slurry film is 100 μm.

[0042] This embodiment also provides a method for preparing a lithium-ion battery negative electrode, the method comprising the following steps:

[0043] (1) A slurry is obtained by mixing N-type conductive organic material, negative electrode material, conductive agent, binder and solvent. The N-type conductive organic material includes polyaniline and polydiphenylamine. The negative electrode material is natural graphite. The conductive agent is carbon black. The binder is sodium carboxymethyl cellulose. The solvent is water. The mass ratio of negative electrode material, conductive agent and binder is 95:2:3. The amount of N-type conductive organic material added accounts for 3 wt% of the weight of the slurry film. The amount of solvent added accounts for 50 wt% of the weight of the slurry. The secondary particle D50 particle size of the N-type conductive organic material is 15 μm.

[0044] (2) The slurry described in step (1) is coated onto the current collector and dried to form a slurry film with a thickness of 100 μm to obtain the negative electrode of the lithium-ion battery.

[0045] Example 2

[0046] This embodiment provides a lithium-ion battery negative electrode, which includes a current collector and a slurry film coating the current collector; the slurry film includes an N-type conductive organic material; the N-type conductive organic material includes perylene tetracarboxylic anhydride and perylene tetracarboxylic dianhydride (mass ratio 1:1); the slurry film also includes a negative electrode main material, a conductive agent, and a binder, wherein the negative electrode main material is hard carbon, the conductive agent is graphite, the binder is lithium carboxymethyl cellulose, the mass ratio of the negative electrode main material, the conductive agent, and the binder is 90:3:2, the amount of N-type conductive organic material added accounts for 0.5 wt% of the weight of the slurry film, the secondary particle D50 particle size of the N-type conductive organic material is 10 μm, and the thickness of the slurry film is 50 μm.

[0047] This embodiment also provides a method for preparing a lithium-ion battery negative electrode, the method comprising the following steps:

[0048] (1) A slurry is obtained by mixing N-type conductive organic material, negative electrode material, conductive agent, binder and solvent. The N-type conductive organic material includes perylene tetracarboxylic anhydride and perylene tetracarboxylic dianhydride. The negative electrode material is hard carbon. The conductive agent is graphite. The binder is lithium carboxymethyl cellulose. The solvent is water. The mass ratio of the negative electrode material, conductive agent and binder is 90:3:2. The amount of N-type conductive organic material added accounts for 0.5 wt% of the weight of the slurry film. The amount of solvent added accounts for 40 wt% of the weight of the slurry. The secondary particle D50 particle size of the N-type conductive organic material is 10 μm.

[0049] (2) The slurry described in step (1) is coated onto the current collector and dried to form a slurry film with a thickness of 50 μm to obtain the negative electrode of the lithium-ion battery.

[0050] Example 3

[0051] This embodiment provides a lithium-ion battery negative electrode, which includes a current collector and a slurry film coating the current collector. The slurry film includes an N-type conductive organic material. The N-type conductive organic material includes phthalimide and naphthalimide (mass ratio 1:1). The slurry film also includes a negative electrode main material, a conductive agent, and a binder. The negative electrode main material is silicon suboxide, the conductive agent is carbon nanotubes, and the binder is styrene-butadiene rubber. The mass ratio of the negative electrode main material, the conductive agent, and the binder is 98:1:1. The amount of N-type conductive organic material added accounts for 5 wt% of the weight of the slurry film. The secondary particle D50 particle size of the N-type conductive organic material is 20 μm, and the thickness of the slurry film is 150 μm.

[0052] This embodiment also provides a method for preparing a lithium-ion battery negative electrode, the method comprising the following steps:

[0053] (1) A slurry is obtained by mixing N-type conductive organic material, negative electrode material, conductive agent, binder and solvent. The N-type conductive organic material includes phthalimide and naphthalimide. The negative electrode material is silicon suboxide. The conductive agent is carbon nanotube. The binder is styrene-butadiene rubber. The solvent is N-methylpyrrolidone. The mass ratio of negative electrode material, conductive agent and binder is 98:1:1. The amount of N-type conductive organic material added accounts for 5 wt% of the weight of the slurry film. The amount of solvent added accounts for 60 wt% of the weight of the slurry. The secondary particle D50 particle size of the N-type conductive organic material is 20 μm.

[0054] (2) The slurry described in step (1) is coated onto the current collector and dried to form a slurry film with a thickness of 150 μm to obtain the negative electrode of the lithium-ion battery.

[0055] Example 4

[0056] This embodiment provides a lithium-ion battery anode, wherein the amount of N-type conductive organic matter added to the lithium-ion battery anode accounts for 0.25 wt% of the weight of the slurry film, and the rest is the same as in Example 1.

[0057] Example 5

[0058] This embodiment provides a lithium-ion battery anode, wherein the amount of N-type conductive organic matter added to the lithium-ion battery anode accounts for 5.5 wt% of the weight of the slurry film, and the rest is the same as in Embodiment 1.

[0059] Example 6

[0060] This embodiment provides a lithium-ion battery anode, wherein the secondary particles D50 of the N-type conductive organic matter in the lithium-ion battery anode have a particle size of 25 μm, and the rest are the same as in Example 1.

[0061] Example 7

[0062] This embodiment provides a lithium-ion battery anode, wherein the thickness of the slurry film in the lithium-ion battery anode is 30 μm, and the rest is the same as in Embodiment 1.

[0063] Example 8

[0064] This embodiment provides a lithium-ion battery anode, wherein the thickness of the slurry film in the lithium-ion battery anode is 180 μm, and the rest is the same as in Embodiment 1.

[0065] II. Comparative Example

[0066] Comparative Example 1

[0067] This comparative example provides a lithium-ion battery anode, which does not contain N-type conductive organic matter, and is otherwise the same as in Example 1.

[0068] III. Tests and Results

[0069] The prepared negative electrode was assembled into a symmetrical cell, and the EIS of the symmetrical cell was tested in the frequency range of 1 mHz to 10 MHz to calculate the liquid phase resistance of the negative electrode. In addition, the prepared negative electrode was assembled into a lithium-ion battery with the same positive electrode, separator and electrolyte, and the maximum lithium plating current (rate) of the negative electrode was tested in the voltage range of 2.5 to 4.2 V.

[0070] The test results of the above embodiments and comparative examples are shown in Table 1.

[0071] Table 1

[0072] Liquid phase resistance (mΩ) Maximum lithium plating rate Example 1 4.9 4.3C Example 2 4.4 5.4C Example 3 5.3 3.8C Example 4 6.5 3.2C Example 5 5.7 3.6C Example 6 6.1 3.4C Example 7 4.0 5.5C Example 8 7.8 2.0C Comparative Example 1 9.7 1.3C

[0073] The following points can be observed from Table 1:

[0074] (1) As can be seen from the comprehensive examples 1 to 3, the liquid phase resistance of the lithium-ion battery anode provided by the present invention is small, less than 5.3mΩ, with good fast charging performance and a maximum lithium plating rate of more than 3.8C, which improves the performance of the lithium-ion battery anode.

[0075] (2) It can be seen from the combined examples 1 and 4-5 that in example 1, the amount of N-type conductive organic material added is controlled within a specific range. Compared with examples 4-5, the liquid phase resistance is only 4.9mΩ. However, in examples 4-5, the amount of added material is too high or too low, and the liquid phase resistance is as high as 6.5mΩ and 5.7mΩ, respectively. The maximum lithium plating rate also decreases. This shows that the present invention improves the fast charging performance of the negative electrode of lithium-ion battery by controlling the amount of N-type conductive organic material added within a specific range.

[0076] (3) It can be seen from the combined examples of Example 1 and Example 6 that the secondary particle size D50 of the N-type conductive organic material in Example 1 is 15 μm, which is better than the 25 μm of the secondary particle size D50 of the N-type conductive organic material in Example 6. This shows that the present invention preferably controls the secondary particle size D50 of the N-type conductive organic material, which can better improve the performance of lithium-ion batteries.

[0077] (4) As can be seen from the combined examples 1 and 7-8, the thinner the slurry film is, the better its fast charging performance and maximum lithium plating rate. However, if the thickness of the slurry film is too thin, it will easily lead to a decrease in the stability of the battery. Therefore, it is preferred to control it to be 50-150 μm.

[0078] (5) As can be seen from the combined results of Example 1 and Comparative Example 1, the addition of N-type conductive organic material in Example 1 resulted in a liquid phase resistance of 4.9 mΩ and a maximum lithium plating rate of 4.3C compared to Comparative Example 1 without the addition of N-type conductive organic material. In contrast, the liquid phase resistance in Comparative Example 1 was as high as 9.7 mΩ and the maximum lithium plating rate was only 1.3C. This indicates that the present invention significantly improves fast charging performance and maximum lithium plating rate by adding N-type conductive organic material to the negative electrode of lithium-ion battery.

[0079] The applicant declares that the detailed process equipment and process flow of this invention are illustrated through the above embodiments, but this invention is not limited to the above detailed process equipment and process flow, that is, it does not mean that this invention must rely on the above detailed process equipment and process flow to be implemented. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of raw materials for the products of this invention, additions of auxiliary components, and selection of specific methods, all fall within the protection scope and disclosure scope of this invention.

Claims

1. A lithium-ion battery anode, characterized by, The lithium ion battery negative electrode comprises a current collector and a slurry film coated on the current collector; the slurry film comprises N-type conductive organic matter; the N-type conductive organic matter comprises any one or a combination of at least two of polyaniline, polyaniline derivatives, perylene tetracarboxylic dianhydride, perylene tetracarboxylic dianhydride derivatives, aromatic diimide or aromatic diimide derivatives; The N-type conductive organic matter is added in an amount of 0.5-5wt% of the slurry film; the secondary particle D50 particle size of the N-type conductive organic matter is ≤20μm; and the thickness of the slurry film is 50-150μm.

2. The lithium-ion battery anode of claim 1, wherein, The slurry film further comprises a negative electrode main material, a conductive agent and a binder.

3. The lithium-ion battery anode of claim 2, wherein, The negative electrode main material comprises any one or a combination of at least two of natural graphite, artificial graphite, hard carbon, silicon or silicon monoxide.

4. The lithium-ion battery anode of claim 2, wherein, The conductive agent comprises any one or a combination of at least two of carbon black, graphite or carbon nanotubes.

5. The lithium-ion battery anode of claim 2, wherein, The binder comprises any one or a combination of at least two of sodium carboxymethyl cellulose, lithium carboxymethyl cellulose, butadiene styrene rubber, polytetrafluoroethylene or polymethyl methacrylate.

6. The lithium-ion battery anode of claim 2, wherein, The mass ratio of the negative electrode main material, the conductive agent and the binder is (90-98):(1-3):(1-3).

7. The method for preparing a lithium-ion battery negative electrode according to claim 1, characterized in that, The preparation method comprises the following steps: (1) mixing N-type conductive organic matter, a negative electrode main material, a conductive agent, a binder and a solvent to obtain a slurry, wherein the N-type conductive organic matter comprises any one or a combination of at least two of polyaniline, polyaniline derivatives, perylene tetracarboxylic dianhydride, perylene tetracarboxylic dianhydride derivatives, aromatic diimide or aromatic diimide derivatives; (2) coating the slurry of step (1) on a current collector and drying to form a slurry film to obtain a lithium ion battery negative electrode; The N-type conductive organic matter is added in an amount of 0.5-5wt% of the slurry film; the secondary particle D50 particle size of the N-type conductive organic matter is ≤20μm; and the thickness of the slurry film is 50-150μm.

8. The preparation method according to claim 7, characterized in that, The solvent of step (1) comprises water and / or N-methyl pyrrolidone.

9. The preparation method according to claim 7, characterized in that, The amount of the solvent of step (1) added is 40-60wt% of the slurry.

10. Use of the lithium ion battery negative electrode of any one of claims 1-6 in a lithium ion battery.