Preparation method of fast-charging lithium ion battery negative electrode material coated asphalt

Abstract

The invention belongs to the technical field of lithium ion battery negative electrode materials and coated asphalt, and discloses a preparation method of rapidly-charged lithium ion battery negative electrode material coated asphalt. The coated asphalt is prepared by taking any one or more than two of petroleum residual oil, ethylene tar, medium and low temperature coal tar and coal-series asphalt as raw materials, adding a thermoplastic resin compounding agent, and co-doping with a modifying solvent and a doping modifier; the used raw materials are low in value and easy to obtain; after the prepared coated asphalt is carbonized, the optical structure is highly inlaid and isotropic, and the interlayer spacing is relatively large; and after the negative electrode material is coated, the coating effect is uniform, the electrochemical performance is obviously improved, and the high-added-value utilization of the asphalt is realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of anode materials for lithium-ion batteries and coating pitch, and relates to a preparation method of coating pitch for anode materials of fast-charging lithium-ion batteries. Background Art

[0002] With the increasing demand in the consumer electronics market and the electric vehicle industry for shortening the charging time, the development of fast-charging technology has become an important trend in the development of lithium-ion battery technology in recent years. As an important component of lithium-ion batteries, the performance of the anode material itself directly affects the entire battery system. The inherent structure of graphite anode materials limits the rapid transmission of lithium ions, showing slow kinetics and lithium deposition phenomena under fast-charging conditions. Coating graphite anodes with disordered carbon layers can effectively improve this phenomenon and enhance their fast-charging performance.

[0003] Coating graphite anode materials with traditional pitch can cover the active sites on the graphite surface, reduce the occurrence of irreversible side reactions, and increase the cycling stability. However, the tendency of pitch to transform into ordered carbon layers after carbonization is not conducive to the rapid shuttling of lithium ions, and develops into anisotropic flaky and fibrous microstructures under a polarized light microscope.

[0004] At the same carbonization temperature, the carbon material layer spacing with a fine mosaic structure and isotropic structure is larger than that of flaky and fibrous structures, with more carbon layer defects, which is conducive to the passage of lithium ions from all directions and has stronger rate performance. The formation of some mosaic structures is due to the fact that asphaltenes containing higher porphyrin compounds have a disordered carbon layer structure similar to that after carbonization of biomass-based raw materials after carbonization. However, the content of porphyrin compounds in asphalt-based raw materials is low, and the consistency of raw materials cannot be well guaranteed. There is an urgent need to develop a material and preparation process that can solve the above problems. Summary of the Invention

[0005] In order to overcome the deficiencies of the prior art, the present invention provides a preparation method of coating pitch for anode materials of fast-charging lithium-ion batteries. The coating pitch is prepared by using any one or more of petroleum residue oil, ethylene tar, medium and low temperature coal tar, and coal-based pitch as raw materials, adding a thermoplastic resin-based compounding agent, and co-doping with a modified solvent and a doping modifier; the carbonized coating pitch has a highly mosaic structure and a large layer spacing, which is conducive to the rapid shuttling of lithium ions.

[0006] The above object of the present invention is achieved by the following technical solutions:

[0007] A preparation method of pitch-coated anode material for fast-charging lithium-ion batteries, using any one or more of petroleum residue oil, ethylene tar, medium and low-temperature coal tar, and coal pitch as raw materials, adding a thermoplastic resin-based compounding agent to obtain a fast-charging coated pitch precursor, using a nitrogen-containing heterocyclic liquid as a modifying solvent, adding a doping modifier, and successively undergoing doping modification, high-temperature polymerization, oxidative crosslinking, and vacuum distillation or molecular distillation processes to obtain a fast-charging coated pitch with a highly intercalated or isotropic structure after carbonization.

[0008] The thermoplastic resin-based compounding agent is any one or more of phenolic resin, polyamide, polyphenylene sulfide, polyvinylpyrrolidone, and polyimide.

[0009] The modifying solvent is any one of wash oil, cracked naphthalene fraction, and NMP.

[0010] The doping modifier is thiourea.

[0011] Furthermore, the specific steps of the above preparation method are as follows:

[0012] 1) Raw material compounding

[0013] Using any one or more of petroleum residue oil, ethylene tar, medium and low-temperature coal tar, and coal pitch as raw materials, adding any one or more of thermoplastic resin-based compounding agents such as phenolic resin, polyamide, polyphenylene sulfide, polyvinylpyrrolidone, and polyimide, placing them in a reaction kettle, and stirring at 100 - 300 °C for 0.5 - 2 h to obtain a precursor;

[0014] 2) Doping modification

[0015] Adding a modifying solvent and a doping modifier to the precursor for mixing, with a mixing temperature of 180 °C - 200 °C and a mixing time of 2 - 5 h to obtain a doped modified pitch;

[0016] 3) High-temperature polymerization

[0017] Placing the doped modified pitch in a reaction kettle, heating it to 250 °C - 350 °C at a heating rate of 3 °C / min - 5 °C / min, maintaining a constant temperature reaction for 0.5 h - 5 h, and then heating it to 330 °C - 400 °C again, and maintaining a constant temperature for the polymerization reaction for 1 h - 8 h to obtain a polymerized pitch;

[0018] 4) Oxidative crosslinking

[0019] Further oxidatively crosslinking the polymerized pitch, with a temperature of 330 °C - 380 °C, a gas flow rate of 3 L / min - 300 L / min, and an oxidation time of 2 h - 6 h to obtain an oxidized pitch with a softening point greater than 100 °C;

[0020] 5) Reprocessing (vacuum distillation or molecular distillation)

[0021] The oxidized asphalt is separated into light and heavy components through a vacuum distillation or molecular distillation device. The parameters used for vacuum distillation are as follows: Vacuum pressure: -0.08 to -0.1 Mpa;

[0022] Distillation temperature: 330°C to 360°C;

[0023] Stirring speed: 150 rpm to 300 rpm;

[0024] Time: 1 h to 5 h;

[0025] Under rotational conditions, the oxidized asphalt is distilled by molecular distillation to obtain the fast-charging type coated asphalt material. The parameters used are as follows:

[0026] Distillation temperature: 280°C to 330°C;

[0027] Vacuum pressure: 30 Pa to 200 Pa;

[0028] Rotational speed: 200 rpm to 400 rpm;

[0029] The fast-charging type coated asphalt material is prepared by the method of vacuum distillation or molecular distillation.

[0030] Furthermore, in the step 1), the asphalt content in the raw materials accounts for 50 wt% to 100 wt% of the blended raw materials, and the thermoplastic resin-based compounding agent accounts for 0 wt% to 50 wt% of the blended raw materials.

[0031] Furthermore, in the step 2), the addition amount of the modification solvent is 10 wt% to 200 wt% of the blended raw materials, and the addition amount of the doping modifier is 0.5 wt% to 5 wt% of the blended raw materials.

[0032] Furthermore, in the step 1) and the step 2), the stirring speed is 200 rpm to 700 rpm.

[0033] Furthermore, the softening point of the fast-charging type coated asphalt material obtained by the method of vacuum distillation or molecular distillation is 120°C to 280°C.

[0034] The present invention requests protection for the application of the coated asphalt material prepared by the above preparation method in the negative electrode material of a lithium-ion battery.

[0035] The present invention uses petroleum residue, ethylene tar, medium and low temperature coal tar, and coal pitch as raw materials. The raw materials used are of low value and easy to obtain; the optical structure of the coated asphalt obtained after carbonization is highly mosaicked and isotropic, with a relatively large layer spacing; after the negative electrode material is coated, the coating effect is uniform, and the electrochemical performance is significantly improved, realizing the high-value utilization of asphalt. The present invention introduces heteroatoms into the asphalt molecules, so that after carbonization, aromatic lamellae with more defects and a relatively large layer spacing are formed.

[0036] The beneficial effects of the present invention compared with the prior art are as follows:

[0037] 1) The present invention uses petroleum resid, ethylene tar, medium and low temperature coal tar, and coal pitch as raw materials. There is a large amount of stable output of raw materials in the market, which are easy to obtain and have low prices.

[0038] 2) The modified wash oil and cracked naphthalene fraction used in the present invention contain some nitrogen heteroaromatic compounds and are good solvents for asphalt. After mixing with thiourea, sulfur replaces pyrrole nitrogen in a thiophene-like structure, and the formed active site carbon-sulfur covalent bond is not easily cleaved and rearranged, and stably exists in the asphalt to play a synergistic doping effect. The obtained coating material shows a stable and uniform fine mosaic structure in the polarized light micrograph after carbonization, and the layer spacing is larger than that of ordinary coating materials.

[0039] 3) Some resin solvents such as NMP can dissolve both asphalt and resin at the same time, modify and compound the raw materials in a specific ratio, and introduce sulfur elements in a doping manner before polymerization, which improves the overall disorder degree of the coating material, expands the layer spacing after carbonization of the material, and shows a fine mosaic structure or an isotropic structure similar to that of hard carbon after carbonization.

[0040] 4) Through the raw material mixing and polymerization process, the raw materials undergo a polycondensation reaction, and some aromatic light components containing porphyrin-like compounds are polymerized into gum and asphaltene, regulating the raw material structure and simultaneously increasing the raw material yield; in addition, ammonia gas produced by the cracking of the doping modifier is discharged during the high-temperature polymerization process, avoiding the phenomenon of increased specific surface area caused by the rapid escape of gas during the carbonization process of the coating material. Description of the Drawings

[0041] Figure 1 Polarized light micrograph of the carbonized coating asphalt material prepared in Example 1. Among them, Figures (a), (b), and (c) are all partial polarized light pictures after carbonization in Example 1.

[0042] Figure 2 Polarized light micrograph of the carbonized coating asphalt material prepared in Example 2. Among them, Figures (a), (b), and (c) are all partial polarized light pictures after carbonization in Example 2.

[0043] Figure 3 Polarized light micrograph of the carbonized coating asphalt material prepared in Example 3. Among them, Figures (a), (b), and (c) are all partial polarized light pictures after carbonization in Example 3.

[0044] Figure 4 Polarized light micrograph of the carbonized coating asphalt material prepared in Example 4. Among them, Figures (a), (b), and (c) are all partial polarized light pictures after carbonization in Example 4.

[0045] Figure 5Cross-sectional scanning electron micrograph of the coated asphalt material prepared in Example 1 after carbonization with the negative electrode material. Detailed implementation manners

[0046] The present invention will be described in detail below through specific implementation manners, but the protection scope of the present invention is not limited. Unless otherwise specified, the experimental methods used in the present invention are all conventional methods, and the experimental equipment, materials, reagents, etc. used can be obtained from commercial channels.

[0047] The present invention provides a preparation method for coating asphalt on the negative electrode material of a fast-charging lithium-ion battery. This method uses any one or two or more of petroleum residue oil, ethylene tar, medium and low temperature coal tar, and coal pitch as raw materials, and adds phenolic resin, polyphenylene sulfide, polyimide thermoplastic resin-based compounding agents to obtain a fast-charging coated asphalt precursor. Using wash oil, cracked naphthalene fraction, NMP-containing nitrogen heterocyclic liquid as a modified solvent and thiourea as a doping modifier, through doping modification, high-temperature polymerization, oxidative cross-linking, vacuum distillation or molecular distillation processes in sequence, a fast-charging coated asphalt with a highly inlaid or isotropic structure after carbonization is obtained; it includes the following steps:

[0048] 1) Raw material compounding

[0049] Using one or more of petroleum residue oil, ethylene tar, medium and low temperature coal tar, and coal pitch as raw materials, adding one or more of phenolic resin, polyphenylene sulfide, polyimide and other thermoplastic resin-based compounding agents, placing them in a reaction kettle and stirring at 100 - 300 °C for 0.5 - 2 h to obtain a precursor;

[0050] 2) Doping modification

[0051] Adding a modified solvent and a doping modifier to the precursor for mixing, with a mixing temperature of 180 °C - 200 °C and a mixing time of 2 - 5 h to obtain a doped modified asphalt;

[0052] 3) High-temperature polymerization

[0053] Placing the doped modified asphalt in a reaction kettle, heating it to 250 °C - 350 °C at a heating rate of 3 °C / min - 5 °C / min, maintaining a constant temperature reaction for 0.5 h - 5 h, and then heating it to 330 °C - 400 °C again, and maintaining a constant temperature for the polymerization reaction for 1 h - 8 h to obtain a polymerized asphalt;

[0054] 4) Oxidative cross-linking

[0055] Further performing oxidative cross-linking on the polymerized asphalt, with a temperature of 330 °C - 380 °C, an air flow rate of 3 L / min - 300 L / min, and an oxidation time of 2 h - 6 h to obtain an oxidized asphalt with a softening point greater than 100 °C;

[0056] 5) Reprocessing (vacuum distillation or molecular distillation)

[0057] The oxidized asphalt is separated into light and heavy components through a vacuum distillation or molecular distillation device. The parameters used for vacuum distillation are as follows: Vacuum pressure: -0.08 to -0.1 Mpa;

[0058] Distillation temperature: 330°C to 360°C;

[0059] Stirring speed: 150 rpm to 300 rpm;

[0060] Time: 1 h to 5 h;

[0061] Under rotational conditions, the oxidized asphalt is distilled by molecular distillation to obtain the fast-charging type coated asphalt material. The parameters used are as follows:

[0062] Distillation temperature: 280°C to 330°C;

[0063] Vacuum pressure: 30 Pa to 200 Pa;

[0064] Rotation speed: 200 rpm to 400 rpm;

[0065] The fast-charging type coated asphalt material is prepared by vacuum distillation or molecular distillation.

[0066] In the raw material compounding step, the asphalt content in the raw materials accounts for 50 wt% to 100 wt% of the blended raw materials, and the thermoplastic resin-based compounding agent accounts for 0 wt% to 50 wt% of the blended raw materials.

[0067] In the doping modification step, the addition amount of the modification solvent is 10 wt% to 200 wt% of the blended raw materials, and the addition amount of the doping modifier is 0.5 wt% to 5 wt% of the blended raw materials.

[0068] In the raw material compounding and doping modification steps, the stirring speed is 200 rpm to 700 rpm.

[0069] The softening point of the fast-charging type coated asphalt material obtained by the vacuum distillation or molecular distillation method is 120°C to 280°C.

[0070] The present invention will be further described below by way of examples, but the present invention is not limited to the scope of the examples described herein. Based on the examples of the present invention, any simple modification, equivalent change or modification made by those of ordinary skill in the art without creative efforts still falls within the scope of the present invention.

[0071] Example 1:

[0072] Take a certain mass of petroleum residue and mix it evenly with ethylene tar accounting for 20 wt% of the blend raw materials. Place it in a reaction kettle, stir at 150 °C for 1 h to ensure thorough mixing of the two raw materials. Add wash oil accounting for 50 wt% of the mixed raw materials to the compounded raw materials for mixing. The mixing temperature is 180 °C and the mixing time is 0.5 h. After mixing evenly, add thiourea accounting for 2 wt% of the mixed raw materials for blending. The mixing temperature is 220 °C and the mixing time is 3 h to obtain doped modified asphalt. Polymerize the doped modified asphalt in the reaction kettle, heat it up to 330 °C at a rate of 5 °C / min for polymerization for 1 h, and then heat it up to 360 °C at a rate of 5 °C / min for polymerization for 4 h to obtain polymerized asphalt. Oxidatively crosslink the polymerized asphalt. The oxidative crosslinking temperature is 360 °C and keep it at a constant temperature for 3 h to obtain oxidized asphalt. Add the oxidized asphalt into a short-path molecular distillation apparatus, set the temperature at 280 °C, control the vacuum pressure of the short-path molecular distillation apparatus at 100 Pa, the rotation speed at 200 rpm, and the distillation time at 3 h to obtain a fast-charging type coated asphalt material with a highly intercalated structure. The performance indicators are shown in Table 1, and the polarized light microscope pictures after carbonization are shown in Figure 1 ; After coating the asphalt with the anode material and carbonizing it, the cross-sectional scanning electron microscope pictures are shown in Figure 5 ; Assemble it into a coin-type lithium-ion battery for electrochemical testing. The battery test results are shown in Table 2.

[0073] Example 2:

[0074] Take a certain mass of petroleum residue and mix it evenly with medium and low temperature coal tar accounting for 20 wt% of the blend raw materials. Place it in a reaction kettle, stir at 150 °C for 1 h. After ensuring thorough mixing of the two raw materials, stir phenolic resin accounting for 20 wt% of the blend raw materials at 150 °C for 1 h to obtain compounded raw materials. Add cracked naphthalene fraction accounting for 20 wt% of the mixed raw materials to the compounded raw materials for mixing. The mixing temperature is 180 °C and the mixing time is 0.5 h. After mixing evenly, add thiourea accounting for 2 wt% of the mixed raw materials for blending. The mixing temperature is 220 °C and the mixing time is 3 h to obtain doped modified asphalt. Polymerize the doped modified asphalt in the reaction kettle, heat it up to 330 °C at a rate of 5 °C / min for polymerization for 1 h, and then heat it up to 360 °C at a rate of 2 °C / min for polymerization for 4 h to obtain polymerized asphalt. Oxidatively crosslink the polymerized asphalt. The oxidative crosslinking temperature is 360 °C and keep it at a constant temperature for 3 h to obtain oxidized asphalt. Carry out vacuum distillation on the oxidized asphalt, heat it up to 330 °C at a rate of 5 °C / min for distillation for 1 h, and then heat it up to 350 °C at a rate of 1 °C / min for vacuum distillation for 3 h to obtain a fast-charging type coated asphalt material with a highly intercalated structure. The performance indicators are shown in Table 1, and the polarized light microscope pictures after carbonization are shown in Figure 2 ; Assemble it into a coin-type lithium-ion battery for electrochemical testing. The battery test results are shown in Table 2.

[0075] Example 3:

[0076] Take a certain mass of ethylene tar and mix it evenly with coal tar pitch accounting for 10wt% of the blended raw materials. Place it in a reaction kettle, stir at 150°C for 1h to ensure thorough mixing of the two raw materials. Add wash oil accounting for 30wt% of the mixed raw materials as a modifier to the compounded raw materials for mixing. The mixing temperature is 200°C and the mixing time is 0.5h. After thorough mixing, add thiourea accounting for 3wt% of the mixed raw materials for blending. The blending temperature is 220°C and the blending time is 3h to obtain doped modified asphalt. Polymerize the doped modified asphalt in the reaction kettle, heat it up to 330°C at a rate of 5°C / min for polymerization for 1h, and then heat it up to 360°C at a rate of 2°C / min for polymerization for 4h to obtain polymerized asphalt. Oxidatively crosslink the polymerized asphalt. The oxidative crosslinking temperature is 360°C and keep it at a constant temperature for 3h to obtain oxidized asphalt. Perform vacuum distillation on the oxidized asphalt, heat it up to 330°C at a rate of 5°C / min for distillation for 1h, and then heat it up to 360°C at a rate of 1°C / min for vacuum distillation for 2h to obtain a fast-charging type coated asphalt material with a highly intercalated structure. The performance indicators are shown in Table 1, and the polarized light microscope pictures after carbonization are shown in Figure 3 ; Assemble it into a button-type lithium-ion battery for electrochemical testing. The battery test results are shown in Table 2.

[0077] Example 4:

[0078] Take a certain mass of ethylene tar and phenolic resin of equal mass and place them in a reaction kettle. Stir at 180°C for 2h to ensure thorough mixing of the two materials. Add NMP accounting for 200wt% of the mixed raw materials as a modifier to the compounded raw materials for mixing. The mixing temperature is 150°C and the mixing time is 0.5h. After thorough mixing, add thiourea accounting for 3wt% of the mixed raw materials for blending. The blending temperature is 190°C and the blending time is 3h to obtain doped modified asphalt. Polymerize the doped modified asphalt in the reaction kettle, heat it up to 180°C at a rate of 5°C / min for distillation and polymerization for 5h, and then heat it up to 360°C at a rate of 2°C / min for polymerization for 4h to obtain polymerized asphalt. Oxidatively crosslink the polymerized asphalt. The oxidative crosslinking temperature is 360°C and keep it at a constant temperature for 3h to obtain oxidized asphalt. Perform vacuum distillation on the oxidized asphalt, heat it up to 330°C at a rate of 5°C / min for distillation for 1h, and then heat it up to 350°C at a rate of 1°C / min for vacuum distillation for 1h to obtain a fast-charging type coated asphalt material with a highly intercalated structure. The performance indicators are shown in Table 1, and the polarized light microscope pictures after carbonization are shown in Figure 4 ; Assemble it into a button-type lithium-ion battery for electrochemical testing. The battery test results are shown in Table 2.

[0079] Table 1 Performance indicators of the coated asphalt materials prepared in the examples

[0080] Serial number Softening point / °C QI / % CV / % Example 1 151.7 0.35 61.25％ Example 2 197.2 0.68 69.93％ Example 3 250.0 1.61 80.17％ Example 4 183.9 0.46 67.41％

[0081] Table 2 Performance indicators of the materials prepared in the examples after being applied to the negative electrode material granulation and assembled into a button battery

[0082]

[0083] The above-described embodiments are only the preferred embodiments of the present invention, and not all the feasible embodiments of the present invention. For those of ordinary skill in the art, any obvious changes made without departing from the principles and spirit of the present invention should be considered to be included within the scope of protection of the claims of the present invention.

Claims

1. A method for preparing asphalt coated negative electrode material for fast-charging lithium-ion batteries, characterized in that: A fast-filling coated asphalt precursor is prepared by taking any one or more of petroleum residue, ethylene tar, medium-low temperature coal tar and coal tar as raw materials, adding a thermoplastic resin compounding agent, taking a nitrogen-containing heterocyclic liquid as a modification solvent, adding a doping modifier, and sequentially undergoing doping modification, high-temperature polymerization, oxidative cross-linking, vacuum distillation or molecular distillation processes to obtain a fast-filling coated asphalt with a highly mosaic or isotropic structure after carbonization.

2. The method for preparing a fast-charging lithium-ion battery negative electrode material coated with asphalt as claimed in claim 1, characterized in that: The thermoplastic resin compounding agent is any one or more of phenolic resin, polyamide, polyphenylene sulfide, polyvinyl pyrrolidone and polyimide.

3. The method for preparing a fast-charging lithium-ion battery negative electrode material coated with asphalt as claimed in claim 1, characterized in that: The modified solvent is any one of wash oil, cracked naphthalene fraction, and NMP.

4. The method for preparing a fast-charging lithium-ion battery negative electrode material coated with asphalt as claimed in claim 1, characterized in that: The doping modifier is thiourea.

5. The method for preparing a fast-charging lithium-ion battery negative electrode material coated with asphalt as claimed in claim 1, characterized in that: The specific steps are as follows: 1) Raw material compounding Using any one or more of petroleum residue, ethylene tar, medium-low temperature coal tar, coal tar asphalt as raw materials, adding any one or more of thermoplastic resin compounding agents such as phenolic resin, polyamide, polyphenylene sulfide, polyvinyl pyrrolidone, polyimide, etc., placing in a reaction kettle and stirring at 100-300° C. for 0.5-2h to obtain a precursor; 2) Doping modification Adding a modified solvent and a doping modifier into the precursor and mixing them, the mixing temperature is 180° C. to 200° C., and the mixing time is 2 to 5 hours to obtain a doped modified asphalt; 3) High temperature polymerization The doped modified asphalt is placed in a reactor, heated to 250°C to 350°C at a heating rate of 3°C / min to 5°C / min, reacted at a constant temperature for 0.5h to 5h, and then heated to 330°C to 400°C again, and polymerized at a constant temperature for 1h to 8h to obtain polymerized asphalt; 4) Oxidative cross-linking The polymerized asphalt is further subjected to oxidation crosslinking at a temperature of 330°C to 380°C, a gas flow rate of 3L / min to 300L / min, and an oxidation time of 2h to 6h to obtain an oxidized asphalt having a softening point greater than 100°C; 5) Reprocessing The light and heavy components of the oxidized asphalt are separated by vacuum distillation or molecular distillation, and the fast-filling coated asphalt material is prepared by vacuum distillation or molecular distillation.

6. The method for preparing a fast-chargeable lithium-ion battery negative electrode material coated with asphalt as claimed in claim 5, characterized in that: In step 5), the parameters used for vacuum distillation are as follows: vacuum pressure: -0.08 to -0.1 MPa; Distillation temperature: 330℃~360℃; Stirring speed: 150rpm~300rpm; Time: 1h~5h.

7. The method for preparing a fast-charging lithium-ion battery negative electrode material coated with asphalt as claimed in claim 5, characterized in that: In step 5), the molecular distillation is carried out under rotational conditions to obtain oxidized asphalt, and the parameters used are as follows: Distillation temperature: 280℃~330℃; Vacuum pressure: 30Pa~200Pa; Rotation speed: 200rpm~400rpm.

8. The method for preparing a fast-charging lithium-ion battery negative electrode material coated with asphalt as claimed in claim 5, characterized in that: In the step 1), the asphalt content in the raw material accounts for 50wt% to 100wt% of the blended raw material, and the thermoplastic resin compounding agent accounts for 0wt% to 50wt% of the blended raw material.

9. The method for preparing a fast-charging lithium-ion battery negative electrode material coated with asphalt as claimed in claim 5, characterized in that: In the step 2), the amount of the modified solvent added is 10 wt% to 200 wt% of the blended raw materials, and the amount of the doping modifier added is 0.5 wt% to 5 wt% of the blended raw materials.

10. Use of the coated asphalt material prepared by the preparation method according to any one of claims 1 to 9 in negative electrode materials for lithium-ion batteries.

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