A spherical graphite negative electrode material modified by asphalt and molybdenum disulfide and its preparation method and application

Abstract

The present invention discloses a spherical graphite negative electrode material modified by asphalt and molybdenum disulfide, as well as its preparation method and application, belonging to the technical field of preparation of negative electrode materials for lithium-ion batteries. The preparation method comprises the following steps: oxidizing spherical graphite to obtain a first precursor; ball-milling asphalt, a pore-forming agent, and the first precursor to obtain a second precursor; calcining the second precursor to obtain a third precursor; immersing the third precursor in a mixed aqueous solution of sodium molybdate and thiourea to carry out a hydrothermal reaction, filtering, and drying to obtain a spherical graphite negative electrode material modified by asphalt and molybdenum disulfide. The present invention can solve the problems of low specific capacity and unstable cycle faced by graphite negative electrodes, and obtain a negative electrode material with high capacity and excellent cycle performance. It shows significant advantages in terms of electrochemical performance, stability, safety, and cost-effectiveness, and provides new ideas and methods for the development of high-performance negative electrode materials for lithium-ion batteries.

Description

Technical Field

[0001] The present invention belongs to the technical field of new energy material preparation, and specifically relates to a spherical graphite negative electrode material modified by asphalt and molybdenum disulfide, and a preparation method and application thereof. Background Art

[0002] At present, the negative electrode of lithium-ion batteries mainly uses spherical graphite, which has a theoretical specific capacity of 372mAh g -1 Due to the limitation of theoretical specific capacity, if the battery energy density is to be further improved, it must be compounded with other high specific capacity materials. Molybdenum disulfide material has a very high theoretical specific capacity (670mAh g -1 ), high electrical conductivity and excellent cycle stability. Compounding it with graphite could provide strong support for the development of future high-performance lithium-ion battery anode materials. However, molybdenum disulfide easily agglomerates, and if it cannot be evenly dispersed, it will have the opposite effect.

[0003] Modifying the surface of spherical graphite, such as introducing porous carbon materials, and then using related technologies to grow molybdenum disulfide in the porous carbon materials can achieve effective dispersion of molybdenum disulfide and improve the electrochemical performance of the material. From an industrial perspective, asphalt has the advantages of a wide range of sources and a high carbon yield during pyrolysis. If asphalt is used to coat spherical graphite, it will greatly reduce production costs. However, due to the conjugation effect of polycyclic aromatic hydrocarbons in asphalt, asphalt is prone to accumulation and agglomeration during pyrolysis, which is not conducive to complete coating on the surface of spherical graphite, let alone the formation of a porous network structure. In addition, the surface of spherical graphite is highly hydrophobic. Even if it is directly calcined with asphalt, its surface tension is not sufficient for the asphalt to completely infiltrate it. Therefore, the problem of uniformity of material coating has always been difficult to solve.

[0004] When preparing high-performance lithium-ion battery negative electrode materials by combining molybdenum disulfide and spherical graphite, molybdenum disulfide is easy to agglomerate, porous carbon materials are difficult to modify, asphalt coating is easy to stack and agglomerate, the surface is difficult to completely infiltrate, and the uniformity of material coating is difficult to control. It is urgent to find new modification methods and coating technologies to achieve uniform dispersion and efficient utilization of molybdenum disulfide in graphite. Summary of the Invention

[0005] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide a spherical graphite negative electrode material modified by asphalt and molybdenum disulfide, and its preparation method and application, so as to solve the technical problems in lithium-ion battery negative electrode materials, such as easy agglomeration, uneven coating and limited improvement of electrochemical performance when molybdenum disulfide and spherical graphite are compounded.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] The present invention discloses a method for preparing a spherical graphite negative electrode material modified by asphalt and molybdenum disulfide, comprising the following steps:

[0008] S1: oxidizing spherical graphite to obtain a first precursor;

[0009] S2: ball-milling the asphalt, the pore-forming agent, and the first precursor obtained in step S1 to obtain a second precursor;

[0010] S3: calcining the second precursor obtained in step S2 to obtain a third precursor;

[0011] S4: Immerse the third precursor obtained in step S3 in a mixed aqueous solution of sodium molybdate and thiourea to carry out a hydrothermal reaction, filter, and dry to obtain a spherical graphite negative electrode material modified by asphalt and molybdenum disulfide.

[0012] Preferably, in step S1, the atmosphere of the oxidation treatment is air or oxygen; the temperature of the oxidation treatment is 200-400° C.; and the time of the oxidation treatment is 2-8 hours.

[0013] Preferably, in step S2, the mass ratio of the first precursor: asphalt: pore-forming agent is 100: (5-15): (2-10).

[0014] Preferably, in step S2, the pore-forming agent is at least one of zinc chloride, sodium carbonate and sodium chloride.

[0015] Preferably, in step S2, the ball milling speed is 200-500 rpm; the ball-to-material ratio is (10-40):1; and the ball milling time is 0.5-2 h.

[0016] Preferably, in step S3, the calcination temperature is 800-1200° C.; the calcination time is 1-3 hours; and the calcination atmosphere is nitrogen or argon.

[0017] Preferably, in step S4, in the mixed aqueous solution of sodium molybdate and thiourea, the molar ratio of sodium molybdate to thiourea is 1:2; the mass ratio of the third precursor to sodium molybdate is 100:(5-20); and the dosage ratio of the third precursor to the total volume of the solution is 1 g:(5-20) mL.

[0018] Preferably, in step S4, the temperature of the hydrothermal reaction is 160-220° C.; and the time of the hydrothermal reaction is 5-12 h.

[0019] The invention also discloses a spherical graphite negative electrode material prepared by the above-mentioned preparation method and modified by asphalt and molybdenum disulfide.

[0020] The present invention also discloses the use of the asphalt prepared by the above preparation method in conjunction with molybdenum disulfide modified spherical graphite negative electrode material in the preparation of lithium ion battery negative electrode materials.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The present invention discloses a preparation method of a spherical graphite negative electrode material modified by asphalt and molybdenum disulfide. First, the spherical graphite is oxidized to improve its surface roughness and wettability to asphalt, so that the asphalt can be more evenly coated on the graphite surface. Then, ball milling is used to uniformly disperse it with the asphalt, avoiding the uneven coating problem caused by insufficient surface tension of asphalt in traditional methods. By adding a pore-forming agent, a porous carbon material coating is generated on the surface of the spherical graphite during the calcination process. These porous structures not only provide abundant sites for the growth of molybdenum disulfide, but also promote the uniform dispersion of molybdenum disulfide on the graphite surface, effectively preventing the agglomeration of molybdenum disulfide, thereby improving the overall electrochemical performance of the composite material. In order to further improve the performance of spherical graphite, molybdenum disulfide is grown in the porous carbon material by an impregnation process and a hydrothermal method. Molybdenum disulfide grows in the highly conductive porous carbon material, and its high theoretical specific capacity is fully utilized, complementing the spherical graphite, significantly improving the overall capacity of the negative electrode material. At the same time, the porous carbon material and the asphalt coating work together to improve the material's electron transfer efficiency and ion diffusion rate, thereby improving the battery's rate performance and cycle stability. Furthermore, the hydrothermal process can remove functional groups such as hydroxyl and carboxyl groups generated during the oxidation of the spherical graphite, ultimately significantly improving the material's capacity and stability. The asphalt-modified spherical graphite negative electrode material obtained by the preparation method disclosed in the present invention can address the problems of low specific capacity and unstable cycling faced by graphite negative electrodes, resulting in a negative electrode material with high capacity and excellent cycle performance.

[0023] The present invention also discloses a spherical graphite negative electrode material modified with asphalt and molybdenum disulfide obtained by the above-mentioned preparation method, which has high specific capacity and energy density, can store more electrical energy, and thus improve the overall energy density of the battery. The combination of the asphalt coating layer and the porous carbon material provides an additional protective barrier for the graphite negative electrode, effectively reducing the volume change of the graphite during the charge and discharge process, and preventing the occurrence of structural damage and pulverization. At the same time, molybdenum disulfide itself also has good structural stability and can maintain a high capacity retention rate over multiple charge and discharge cycles. The introduction of porous carbon material and molybdenum polysulfide improves the transmission path of lithium ions and increases the ionic conductivity of the material. This enables the battery to absorb and release lithium ions more quickly, thereby improving the battery's fast charging performance and meeting the demand for fast charging in modern electronic devices. The asphalt coating helps stabilize the structure of the negative electrode material, reduces internal stress changes caused by overcharging or over-discharging, and thus reduces the risk of battery damage due to overcharging or over-discharging. This improves the safety performance of the battery and extends the battery's service life. The asphalt coating prevents direct contact between the electrolyte and the graphite anode, reducing electrolyte co-embedding on the graphite surface and thus reducing irreversible capacity loss. This helps improve the battery's cycle efficiency and energy utilization. The asphalt-coated spherical graphite anode material, in combination with molybdenum disulfide, demonstrates significant advantages in specific capacity, cycle stability, fast-charging performance, safety, and cost, offering a new solution for improving lithium-ion battery performance.

[0024] The present invention also discloses the use of asphalt prepared by the above-mentioned preparation method in conjunction with molybdenum disulfide-modified spherical graphite negative electrode materials in the preparation of lithium-ion battery negative electrode materials. The introduction of molybdenum disulfide brings additional specific capacity contribution to the negative electrode material. Its high theoretical specific capacity significantly improves the overall specific capacity of the composite material, thereby increasing the energy density of the lithium-ion battery. The presence of the porous carbon material not only provides more active sites for the insertion and deinsertion of lithium ions, but also shortens the transmission path of lithium ions, further increasing the energy density of the battery. The synergistic effect of the asphalt coating layer and the porous carbon material effectively reduces the volume change of the graphite negative electrode during the charge and discharge process, prevents structural damage and pulverization, and thus improves the cycle stability of the battery. The introduction of porous carbon material and molybdenum polysulfide improves the ionic conductivity of the negative electrode material, allowing the battery to absorb and release lithium ions more quickly, thereby improving the fast charging performance of the battery. During the fast charging process, the negative electrode material is prone to polarization, resulting in a decrease in charging efficiency. The asphalt-coated molybdenum disulfide-modified spherical graphite negative electrode material can effectively reduce the occurrence of polarization and improve fast charging efficiency. Both molybdenum disulfide and asphalt maintain good stability at high temperatures, which helps improve battery safety in high-temperature environments. The preparation process for asphalt-modified spherical graphite anode materials with molybdenum disulfide is relatively simple and easy, making it suitable for large-scale industrial production, helping to improve production efficiency and reduce production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The composite material 0.2A g was prepared in Example 1 of the present invention -1 Cycle performance diagram;

[0026] Figure 2 The composite material 0.3A g was prepared in Example 2 of the present invention. -1 Cycle performance diagram. DETAILED DESCRIPTION

[0027] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0028] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0029] The theories or mechanisms described and disclosed herein, whether correct or incorrect, should not limit the scope of the present invention in any way, that is, the present invention can be implemented without being limited by any specific theory or mechanism.

[0030] Herein, all features such as values, amounts, amounts, and concentrations defined in numerical ranges or percentage ranges are for brevity and convenience only. Accordingly, the description of numerical ranges or percentage ranges should be considered to include and specifically disclose all possible subranges and individual values ​​within the range (including integers and fractions).

[0031] In this document, unless otherwise specified, “include,” “including,” “contains,” “has” or similar terms cover the meanings of “consisting of” and “mainly consisting of,” for example, “A includes a” covers the meanings of “A includes a and other” and “A only includes a.”

[0032] In this document, for the sake of brevity, not all possible combinations of the various technical features in each embodiment or example are described. Therefore, as long as there are no contradictions in the combination of these technical features, the various technical features in each embodiment or example can be combined in any way, and all possible combinations should be considered to be within the scope of this specification.

[0033] Below in conjunction with specific embodiment, further set forth the present invention.Should be understood that these embodiments are only used to illustrate the present invention and are not used in limiting the scope of the present invention.In addition, should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall equally within the scope limited by the appended claims of the application.

[0034] The following examples were prepared using conventional instruments and equipment in the art. Experimental methods in the following examples, where specific conditions are not specified, were generally performed under conventional conditions or according to the conditions recommended by the manufacturer. The various raw materials used in the following examples, unless otherwise specified, were conventional commercially available products, with specifications conventional in the art. In the present specification and the following examples, unless otherwise specified, "%" indicates percentage by weight, "part" indicates parts by weight, and "ratio" indicates weight ratio.

[0035] The present invention is described in further detail below with reference to the accompanying drawings:

[0036] The present invention discloses a method for preparing a spherical graphite negative electrode material modified by asphalt and molybdenum disulfide, comprising the following steps:

[0037] The spherical graphite is oxidized in an oxidizing atmosphere to obtain a first precursor;

[0038] The first precursor, asphalt and pore-forming agent are mixed by ball milling to obtain a second precursor;

[0039] calcining the second precursor at a set temperature and atmosphere to obtain a third precursor;

[0040] The third precursor is immersed in a mixed aqueous solution of sodium molybdate and thiourea to undergo a hydrothermal reaction, and the product is filtered and dried to obtain a spherical graphite negative electrode material modified by asphalt and molybdenum disulfide.

[0041] Preferably, the pre-oxidation atmosphere of graphite is air or oxygen, the pre-oxidation temperature is 200-400°C, and the pre-oxidation time is 2-8h;

[0042] Preferably, the mass ratio of the first precursor, asphalt and pore-forming agent is 100:(5-15):(2-10);

[0043] Preferably, the pore-forming agent is at least one of zinc chloride, sodium carbonate and sodium chloride;

[0044] Preferably, the ball milling speed is between 200 and 500 rpm, the ball-to-material ratio is (10-40):1, and the ball milling time is 0.5-2 h;

[0045] Preferably, the calcination temperature is 800-1200°C, the time is 1-3 hours, and the calcination atmosphere is nitrogen or argon;

[0046] Preferably, the molar ratio of sodium molybdate to thiourea is 1:2, the mass ratio of spherical graphite to sodium molybdate is 100:(5-20), and the mass volume ratio of spherical graphite to the total volume of the solution is 1 g:(5-20) mL;

[0047] Preferably, the hydrothermal reaction temperature is 160-220°C and the hydrothermal time is 5-12h;

[0048] The final composite material is mainly used in the negative electrode of lithium-ion batteries.

[0049] The present invention also discloses the asphalt prepared by the above preparation method and the modified spherical graphite negative electrode material of molybdenum disulfide. -1 At a current density of 1.5 GHz, the initial specific capacity is 589 mAh g -1 , which is much higher than the theoretical specific capacity of traditional spherical graphite negative electrode materials (372mAh g -1 This indicates that the modification of asphalt and molybdenum disulfide significantly improves the lithium storage capacity of the negative electrode material. The specific capacity is 476 mAh g after 300 cycles. -1 , the capacity retention rate was 80.8%. At a slightly higher current density of 0.3A g -1 The initial specific capacity is 521 mAh g -1 The initial specific capacity remains at 521 mAh g -1 , indicating that the material can maintain high lithium storage performance under different current conditions. The specific capacity is 417 mAh g after 300 cycles. -1 Although the specific capacity retention rate is slightly lower, it still shows good cycle stability. This shows that the modified negative electrode material has a stable structure during multiple charge and discharge processes and can effectively resist volume change and structural damage.

[0050] The present invention also discloses the use of the asphalt synergistic molybdenum disulfide modified spherical graphite negative electrode material prepared by the above preparation method in the preparation of lithium-ion battery negative electrode materials. The introduction of molybdenum disulfide brings additional specific capacity contribution to the negative electrode material. The presence of porous carbon material not only provides more active sites for the embedding and deintercalation of lithium ions, but also shortens the transmission path of lithium ions, further improving the energy density of the battery. The synergistic effect of the asphalt coating layer and the porous carbon material effectively reduces the volume change of the graphite negative electrode during the charge and discharge process, prevents the occurrence of structural damage and pulverization, and thus improves the cycle stability of the battery. The preparation process of the asphalt synergistic molybdenum disulfide modified spherical graphite negative electrode material is relatively simple and easy, suitable for large-scale industrial production, and helps to improve production efficiency and reduce production costs.

[0051] Example 1

[0052] A method for preparing a spherical graphite negative electrode material modified by asphalt and molybdenum disulfide, comprising the following steps:

[0053] 100g of spherical graphite was oxidized in air at 200°C for 8h, then placed in a ball mill along with 5g of pitch and 10g of zinc chloride. Milling was performed at 500rpm for 0.5h at a ball-to-material ratio of 10:1. The resulting product was calcined at 800°C for 1h under nitrogen. The resulting powder was then immersed in a mixed solution of sodium molybdate and thiourea (5g sodium molybdate, a 1:2 molar ratio of sodium molybdate to thiourea, and a total volume of 500ml). The solution was hydrothermally treated at 160°C for 12h. The resulting material was filtered, washed, and dried to obtain a pitch-coated molybdenum disulfide-modified spherical graphite anode material.

[0054] See also Figure 1 The composite material 0.2Ag was prepared in Example 1 of the present invention -1 Cycle performance diagram; As can be seen from the figure, the negative electrode material prepared in Example 1 was coated on copper foil to prepare the negative electrode, PP was used as the separator, 1 mol / L LiPF6 (the solvent was a mixture of ethylene carbonate and dimethyl carbonate with a volume ratio of 1:1) was used as the electrolyte and the lithium sheet was assembled into a button cell for electrochemical performance testing. -1 The initial specific capacity is 589 mAh g -1 The specific capacity is 476 mAh g after 300 cycles. -1 .

[0055] Example 2

[0056] A method for preparing a spherical graphite negative electrode material modified by asphalt and molybdenum disulfide, comprising the following steps:

[0057] 100g of spherical graphite was oxidized in air at 400°C for 2h, then placed in a ball mill along with 15g of pitch and 2g of sodium carbonate. Milling was performed at 200rpm for 2h at a ball-to-material ratio of 40:1. The resulting product was calcined at 1200°C for 3h under argon. The resulting powder was then immersed in a mixed solution of sodium molybdate (20g) and thiourea (1:2) in a total volume of 2000ml. The solution was hydrothermally treated at 220°C for 5h. The resulting material was filtered, washed, and dried to obtain a pitch-coated, molybdenum disulfide-modified spherical graphite anode material.

[0058] See also Figure 2 The composite material 0.3Ag was prepared in Example 2 of the present invention -1 Cycle performance diagram; As can be seen from the figure, the negative electrode material prepared in Example 2 was coated on copper foil to prepare the negative electrode, PP was used as the separator, 1 mol / L LiPF6 (the solvent was a mixture of ethylene carbonate and dimethyl carbonate with a volume ratio of 1:1) was used as the electrolyte and the lithium sheet was assembled into a button cell for electrochemical performance testing, 0.3A g -1 The initial specific capacity is 521 mAh g -1 The specific capacity is 417 mAh g after 300 cycles. -1 .

[0059] Example 3

[0060] A method for preparing a spherical graphite negative electrode material modified by asphalt and molybdenum disulfide, comprising the following steps:

[0061] 100g of spherical graphite was oxidized in oxygen at 250°C for 8h, then placed in a ball mill along with 10g of pitch and 5g of sodium chloride. Milling was performed at 300rpm for 1h at a ball-to-material ratio of 20:1. The resulting product was calcined at 900°C for 1.5h under nitrogen. The resulting powder was then immersed in a mixed solution of sodium molybdate (10g), thiourea (1:2 molar ratio), and 1000ml of solution. The solution was then hydrothermally treated at 180°C for 12h. The resulting material was filtered, washed, and dried to obtain a pitch-coated, molybdenum disulfide-modified spherical graphite anode material.

[0062] Example 4

[0063] A method for preparing a spherical graphite negative electrode material modified by asphalt and molybdenum disulfide, comprising the following steps:

[0064] 100g of spherical graphite was oxidized in air at 300°C for 6h, then placed in a ball mill along with 12g of pitch and 8g of zinc chloride. Milling was performed at 400rpm for 1.5h at a ball-to-material ratio of 30:1. The resulting product was calcined at 1000°C for 2h under argon. The resulting powder was then immersed in a mixed solution of sodium molybdate (15g) and thiourea (1:2) in a total volume of 1500ml. The solution was hydrothermally treated at 200°C for 10h. The resulting material was filtered, washed, and dried to obtain a pitch-coated, molybdenum disulfide-modified spherical graphite anode material.

[0065] Example 5

[0066] A method for preparing a spherical graphite negative electrode material modified by asphalt and molybdenum disulfide, comprising the following steps:

[0067] 100g of spherical graphite was oxidized in air at 350°C for 4h, then placed in a ball mill along with 14g of pitch and 10g of sodium carbonate. Milling was performed at 500rpm for 2h at a ball-to-material ratio of 40:1. The resulting product was calcined at 1100°C for 2.5h under nitrogen. The resulting powder was then immersed in a mixed solution of sodium molybdate and thiourea (20g sodium molybdate, a 1:2 molar ratio of sodium molybdate to thiourea, and a total volume of 2000ml). The solution was hydrothermally treated at 220°C for 8h. The resulting material was filtered, washed, and dried to obtain a pitch-coated molybdenum disulfide-modified spherical graphite anode material.

[0068] The above content is only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A method for preparing a spherical graphite negative electrode material modified by asphalt and molybdenum disulfide, characterized in that: The following steps are involved: S1: oxidizing spherical graphite to obtain a first precursor; the oxidation treatment atmosphere is air or oxygen; the oxidation treatment temperature is 200-400° C.; the oxidation treatment time is 2-8 hours; S2: ball-milling the asphalt, the pore-forming agent, and the first precursor obtained in step S1 to obtain a second precursor; the pore-forming agent is at least one of zinc chloride, sodium carbonate, and sodium chloride; the ball-milling speed is 200-500 rpm; the ball-to-material ratio is (10-40):1; and the ball-milling time is 0.5-2 hours; S3: calcining the second precursor obtained in step S2 to obtain a third precursor; the calcination temperature is 800-1200° C.; the calcination time is 1-3 hours; the calcination atmosphere is nitrogen or argon; S4: Immerse the third precursor obtained in step S3 in a mixed aqueous solution of sodium molybdate and thiourea to carry out a hydrothermal reaction, filter, and dry to obtain a spherical graphite negative electrode material modified by asphalt and molybdenum disulfide.

2. The method for preparing the asphalt-coordinated molybdenum disulfide-modified spherical graphite negative electrode material according to claim 1, characterized in that: In step S2, the mass ratio of the first precursor: asphalt: pore-forming agent is 100: (5-15): (2-10).

3. The method for preparing the asphalt-coordinated molybdenum disulfide-modified spherical graphite negative electrode material according to claim 1, characterized in that: In step S4, in the mixed aqueous solution of sodium molybdate and thiourea, the molar ratio of sodium molybdate to thiourea is 1:2; the mass ratio of the third precursor to sodium molybdate is 100:(5-20); and the usage ratio of the third precursor to the total volume of the solution is 1 g:(5-20) mL.

4. The method for preparing the asphalt-coordinated molybdenum disulfide-modified spherical graphite negative electrode material according to claim 1, characterized in that: In step S4, the temperature of the hydrothermal reaction is 160-220° C.; and the time of the hydrothermal reaction is 5-12 hours.

5. The asphalt-modified spherical graphite negative electrode material prepared by the preparation method according to any one of claims 1 to 4.

6. Use of the asphalt prepared by the preparation method according to any one of claims 1 to 4 in conjunction with molybdenum disulfide modified spherical graphite negative electrode material in the preparation of lithium ion battery negative electrode materials.

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