Hard carbon material doped with heteroatoms and methods of making and using same

Abstract

The present application relates to a kind of hard carbon materials of heteroatom doping and its preparation method and application, belong to hard carbon material field.The preparation method of the hard carbon material of heteroatom doping of the present application includes the following steps: commercial hard carbon is mixed with the compound containing heteroatom in solvent, and first mixture is prepared;The first mixture is sintered by joule heating technology, and the hard carbon material is prepared.The present application uses joule heating technology to have the advantages such as fast temperature rise, high heat efficiency, rapid cooling etc., and commercial hard carbon is doped with heteroatom, can greatly reduce energy consumption, shorten preparation time, effectively improve heteroatom doping content, realize high content heteroatom doping and controllable graphitization on hard carbon surface, improve the electrochemical performance of hard carbon material for sodium ion battery negative electrode material.

Description

Technical Field

[0001] This invention belongs to the field of hard carbon materials technology, and relates to a heteroatom-doped hard carbon material, its preparation method and application. Background Technology

[0002] Hard carbon materials are considered promising anode materials for alkali metal ion energy storage systems such as sodium-ion and potassium-ion batteries due to their advantages of low cost, large interlayer spacing, and abundant active sites. However, their practical application still faces problems such as low initial coulombic efficiency, poor rate performance, and insufficient cycle stability. Traditional methods of heteroatom doping of hard carbon materials using high-temperature pyrolysis suffer from issues such as easy agglomeration of doped atoms, severe heteroatom loss, uneven doping, imprecise microstructure control, high energy consumption, and long cycle time during high-temperature pyrolysis. Summary of the Invention

[0003] In view of this, the purpose of the present invention is to provide a heteroatom-doped hard carbon material, a method for preparing the same, and its application in sodium-ion batteries.

[0004] To achieve the above objectives, the present invention provides the following technical solution: A method for preparing a heteroatom-doped hard carbon material includes the following steps: mixing commercial hard carbon with a compound containing heteroatoms in a solvent to prepare a first mixture; The first mixture was sintered using Joule heating technology to prepare the hard carbon anode material.

[0005] In some embodiments, the Joule heating reaction conditions are: a heating rate of 50℃ / s to 100℃ / s, a holding temperature of 800℃ to 1800℃, and a holding time of 5s to 60s.

[0006] In some embodiments, the Joule heating reaction conditions are: a heating rate of 80℃ / s to 100℃ / s, a holding temperature of 1200℃ to 1500℃, and a holding time of 5s to 20s.

[0007] In some embodiments, the mass ratio of the heteroatom-containing compound to commercial hard carbon is (0.1~4):20.

[0008] In some embodiments, the source of the heteroatom-containing compound includes one or more of boron, phosphorus, nitrogen, sulfur, fluorine, and nickel sources.

[0009] In some embodiments, the boron source includes one or more of boric acid, trimethyl borate, and triphenylboron.

[0010] In some embodiments, the phosphorus source includes one or more of phosphoric acid, polyphosphoric acid, ammonium phosphate, diammonium hydrogen phosphate, triphenyl phosphate, and triethyl phosphate.

[0011] In some embodiments, the nitrogen source includes one or more of urea, melamine, dicyandiamide, ethylenediamine, polyethyleneimine, polyacrylonitrile, polyaniline, imidazole, pyridine, and ethylenediaminetetraacetic acid.

[0012] In some embodiments, the sulfur source includes one or more of dimethyl sulfoxide, thiourea, aminosulfonic acid, p-toluenesulfonic acid, ferric ammonium sulfate, and thiophene.

[0013] In some embodiments, the fluorine source includes one or more of polytetrafluoroethylene, ammonium fluoride, sodium tetrafluoroborate, and polyvinylidene fluoride.

[0014] In some embodiments, the nickel source includes one or more of nickel acetate, nickel oxalate, nickel citrate, nickel acetylacetone, nickel nitrate, nickel chloride, and nickel sulfate.

[0015] In some embodiments, the solvent includes one or more of water, anhydrous ethanol, N-methylpyrrolidone, tetrahydrofuran, N,N-dimethylformamide, acetone, and acetonitrile.

[0016] The present invention also provides a heteroatom-doped hard carbon material, which is prepared by the above-described preparation method.

[0017] The present invention also provides a negative electrode material, wherein the negative electrode material comprises the above-mentioned heteroatom-doped hard carbon material.

[0018] The present invention also provides a sodium-ion battery, wherein the negative electrode of the sodium-ion battery comprises the above-mentioned negative electrode material.

[0019] The beneficial effects of this invention are as follows: This invention utilizes Joule heating technology to rapidly dope commercial hard carbon with heteroatoms, thus preparing a heteroatom-doped hard carbon material. The Joule heating technology, with its advantages of extremely rapid heating, high thermal efficiency, and rapid cooling, significantly reduces energy consumption, shortens preparation time, and effectively increases the heteroatom doping content. This achieves high-content heteroatom doping and controllable graphitization on the hard carbon surface, improving the electrochemical performance of the hard carbon material as a sodium-ion battery anode material.

[0020] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0021] To make the objectives, technical solutions, and advantages of the present invention clearer, the preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein: Figure 1 X-ray diffraction patterns of the hard carbon materials prepared in Examples 1, 9, 10 and Comparative Example 1; Figure 2 The first charge-discharge curves of the hard carbon materials prepared in Examples 1, 4, 5 and 6 in sodium battery testing are shown. Figure 3 The results of rate performance tests of the hard carbon materials prepared in Examples 1, 9, 10 and Comparative Example 1 in sodium batteries are shown. Figure 4 The hard carbon materials prepared in Examples 1, 9, 10 and Comparative Example 1 were applied to sodium batteries, and the constant current charge-discharge cycle test results were obtained at a current density of 1C. Figure 5 The first charge-discharge curves of Example 1 and Comparative Example 1 at a current density of 100 mA / g are shown. Figure 6 The first charge-discharge curves of Example 2 and Comparative Example 2 at a current density of 100 mA / g are shown. Figure 7 The first charge-discharge curves of Example 3 and Comparative Example 3 at a current density of 100 mA / g are shown. Detailed Implementation

[0022] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0023] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual pictures. They should not be construed as limiting the invention. To better illustrate the embodiments of the invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0024] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "front," and "rear" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0025] In alkali metal ion energy storage systems, hard carbon materials are promising anode materials. To improve their electrochemical performance, heteroatom doping is widely used to modulate the electronic structure, interlayer spacing, and surface activity of hard carbon, thereby enhancing ion adsorption, accelerating diffusion kinetics, and optimizing interfacial behavior. Currently, the preparation of heteroatom-doped hard carbon mainly relies on the traditional high-temperature pyrolysis method, which typically involves long-term (several hours to tens of hours) high-temperature treatment in a tube furnace. However, this method has the following significant drawbacks: (1) High energy consumption and long cycle: The traditional pyrolysis process needs to be maintained at high temperature (usually >1000°C) for a long time, resulting in high energy consumption and low preparation efficiency, which is not conducive to large-scale production; (2) Severe loss of heteroatoms: Long-term high-temperature treatment will cause a large number of light heteroatoms such as nitrogen to escape, resulting in low doping content and difficulty in precise control, which affects the regulation effect on the electronic structure of the material; (3) Inaccurate microstructure regulation: In the traditional pyrolysis process, the carbon skeleton is prone to excessive graphitization or structural collapse, making it difficult to maintain appropriate interlayer spacing and porous structure while increasing the degree of graphitization, which affects the ion storage capacity and kinetic performance; (4) Uneven heteroatom doping: Existing heteroatom-doped hard carbon mainly adopts the addition of heteroatom compounds in the process of synthesizing hard carbon to achieve heteroatom doping, which may lead to uneven distribution of doped elements.

[0026] Based on this, the present invention first provides a method for preparing heteroatom-doped hard carbon materials, comprising the following steps: S1: A first mixture is prepared by mixing commercial hard carbon with a compound containing heteroatoms in a solvent.

[0027] In some examples, the mass ratio of the heteroatom-containing compound to commercial hard carbon is (0.1~4):20; preferably, the mass ratio of the heteroatom-containing compound to commercial hard carbon is (1~2):20; more preferably, the mass ratio of the heteroatom-containing compound to commercial hard carbon is 1:10.

[0028] The commercial hard carbon fiber of this invention is applicable to all commercially available hard carbon fiber manufactured by various companies, including but not limited to Kuraray hard carbon fiber (Type 2) and Nagao hard carbon fiber.

[0029] In some of these examples, the source of the heteroatom-containing compound includes one or more of boron, phosphorus, nitrogen, sulfur, fluorine, and nickel sources.

[0030] In some of these examples, the boron source includes one or more of boric acid, trimethyl borate, and triphenylboron.

[0031] In some of these examples, the phosphorus source includes one or more of phosphoric acid, polyphosphoric acid, ammonium phosphate, diammonium hydrogen phosphate, triphenyl phosphate, and triethyl phosphate.

[0032] In some of these examples, the nitrogen source includes one or more of urea, melamine, dicyandiamide, ethylenediamine, polyethyleneimine, polyacrylonitrile, polyaniline, imidazole, pyridine, and ethylenediaminetetraacetic acid.

[0033] In some of these examples, the sulfur source includes one or more of dimethyl sulfoxide, thiourea, aminosulfonic acid, p-toluenesulfonic acid, ferric ammonium sulfate, and thiophene.

[0034] In some of these examples, the fluorine source includes one or more of polytetrafluoroethylene, ammonium fluoride, sodium tetrafluoroborate, and polyvinylidene fluoride.

[0035] In some of these examples, the nickel source includes one or more of nickel acetate, nickel oxalate, nickel citrate, nickel acetylacetone, nickel nitrate, nickel chloride, and nickel sulfate.

[0036] In some examples, the solvent includes one or more of water, anhydrous ethanol, N-methylpyrrolidone, tetrahydrofuran, N,N-dimethylformamide, acetone, and acetonitrile. In some specific examples, the solvent includes water and anhydrous ethanol in a volume ratio of 3:(0.8~1.5).

[0037] In some of these examples, step S1 is followed by a drying and grinding step; in some specific examples, the drying temperature is 50°C to 70°C.

[0038] S2: The first mixture is sintered using Joule heating technology to prepare the hard carbon material.

[0039] In some of these examples, the Joule heating reaction conditions are: a heating rate of 50℃ / s to 100℃ / s, a holding temperature of 800℃ to 1800℃, and a holding time of 5s to 60s.

[0040] In some preferred examples, the Joule heating reaction conditions are: a heating rate of 80℃ / s to 100℃ / s, a holding temperature of 1200℃ to 1500℃, and a holding time of 5s to 20s.

[0041] In some of these examples, the mixture described in this invention is sintered in a Joule-heated reactor.

[0042] This invention utilizes the advantages of Joule heating technology, such as extremely rapid heating, high thermal efficiency, and rapid cooling, to dope commercial hard carbon with heteroatoms. This can significantly reduce energy consumption, shorten reaction time, avoid heteroatom loss, and simultaneously inhibit excessive graphitization of hard carbon.

[0043] The present invention also provides a heteroatom-doped hard carbon material, which is prepared by the above-described preparation method.

[0044] The present invention also provides a negative electrode material, wherein the negative electrode material comprises the above-mentioned heteroatom-doped hard carbon material.

[0045] The present invention also provides a sodium-ion battery, wherein the negative electrode of the sodium-ion battery comprises the above-described negative electrode material.

[0046] This invention applies the prepared heteroatom-doped hard carbon material to the negative electrode of a sodium-ion half-cell. Tests were conducted in a voltage range of 0.01-3V, revealing a discharge specific capacity of 333.6 mAh / g after 500 cycles at a current density of 1C (1C=300 mA / g). Furthermore, discharge specific capacities of 358.17, 341.64, 323.2, 309.81, and 290.82 mAh / g were observed at current densities of 30, 60, 150, 300, and 600 mA / g, respectively, demonstrating good cycle performance and rate capability.

[0047] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0048] For experimental methods in the following examples where specific conditions are not specified, please refer to the guidelines provided in this invention, or follow experimental manuals or conventional conditions in the field, or follow the conditions recommended by the manufacturer, or refer to experimental methods known in the field. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products.

[0049] Commercial hard carbon: Kuraray (Type 2) from Japan Example 1 (1) Dissolve commercial hard carbon and boric acid in a mass ratio of 10:1 (2g hard carbon: 0.2g boric acid) in a mixed solution of 30ml deionized water and 10ml anhydrous ethanol, mix well, dry and grind evenly at 60℃.

[0050] (2) Place the evenly ground powder into a Joule heating reactor and heat it to 1400℃ at 100℃ / s and hold it for 10 s to obtain the desired hard carbon material.

[0051] Example 2 Example 2 is basically the same as Example 1, except that polyphosphoric acid is used instead of boric acid in step (1).

[0052] Example 3 Example 3 is basically the same as Example 1, except that dimethyl sulfoxide is used instead of boric acid in step (1).

[0053] Example 4 Example 4 is basically the same as Example 1, except that the mass ratio of commercial hard carbon to boric acid is 20:1.

[0054] Example 5 Example 5 is basically the same as Example 1, except that the mass ratio of commercial hard carbon to boric acid is 20:3.

[0055] Example 6 Example 6 is basically the same as Example 1, except that the mass ratio of commercial hard carbon to boric acid is 5:1.

[0056] Example 7 Example 7 is basically the same as Example 1, except that the heating rate in step (2) is 50℃ / s.

[0057] Example 8 Example 8 is basically the same as Example 1, except that the heating rate in step (2) is 80℃ / s.

[0058] Example 9 Example 9 is basically the same as Example 1, except that the heat preservation temperature is 1000℃.

[0059] Example 10 Example 10 is basically the same as Example 1, except that the heat preservation temperature is 1800℃.

[0060] Comparative Example 1 Step (1) is the same as in Example 1, but step (2) is different; (2) Place the evenly ground powder into a tube furnace and heat it to 1400℃ at a heating rate of 5℃ / min and hold for 4 hours to obtain the desired hard carbon material.

[0061] Comparative Example 2 Step (1) is the same as in Example 2, but step (2) is different; (2) Place the evenly ground powder into a tube furnace and heat it to 1400℃ at a heating rate of 5℃ / min and hold for 4 hours to obtain the desired hard carbon material.

[0062] Comparative Example 3 Step (1) is the same as in Example 3, but step (2) is different; (2) Place the evenly ground powder into a tube furnace and heat it to 1400℃ at a heating rate of 5℃ / min and hold for 4 hours to obtain the desired hard carbon material.

[0063] Test case 1. Structural testing The hard carbon materials prepared in Example 1 (1400℃, 10s), Example 9 (1000℃, 10s), Example 10 (1800℃, 10s), and Comparative Example 1 (1400℃, 4h) were subjected to XRD testing, and the results are as follows: Figure 1 As shown, from Figure 1 It can be seen that the hard carbon material prepared in Example 1 shows two obvious diffraction peaks at approximately 23° and 43°, which correspond to the (002) and (100) planes of graphite, respectively, indicating that the doping and heat treatment processes did not destroy the microstructure of hard carbon. In Example 9, due to the use of a lower doping temperature, there is still a characteristic peak of boron oxide at around 28°, indicating that heteroatoms were not completely incorporated into the hard carbon. The higher holding temperature in Example 10 corresponds to a sharper graphite peak and more significant graphitization. Comparative Example 1 was prepared by heating in a conventional tube furnace, and the long-term high-temperature heating catalyzed graphitization, causing the (002) peak to shift to a higher angle, resulting in a reduction in interlayer spacing.

[0064] Examples 1 to 3 and Comparative Examples 1 to 3 were subjected to inductively coupled plasma spectroscopy and X-ray photoelectron spectroscopy to measure their heteroatom doping content and surface heteroatom content. The results are shown in Table 1.

[0065] Table 1

[0066] As shown in Table 1, the examples all exhibit higher heteroatom content compared to the comparative examples, indicating that Joule heating can effectively promote heteroatom doping and increase the heteroatom doping content. X-ray photoelectron spectroscopy (XPS) tests show that Joule heating can achieve higher heteroatom doping on the hard carbon surface compared to tube furnace heating, providing more sodium storage sites.

[0067] 2. Electrochemical performance testing The hard carbon materials prepared in the above examples and comparative examples were mixed with acetylene black and polyvinylidene fluoride (PVDF) at a mass ratio of 8:1:1. An appropriate amount of N-methylpyrrolidone (NMP) was then added and mixed thoroughly before being coated onto copper foil and dried in a vacuum drying oven at 60°C. Using a sodium sheet as the counter electrode, a 1M NaPF6 / DME mixture as the electrolyte, and a glass fiber membrane as the separator, CR2032 button cells were assembled in a glove box filled with argon gas and where the water and oxygen levels were both less than 0.01 ppm.

[0068] Test methods and conditions: After the assembled button half-cells were left to stand for 10 hours, the electrochemical performance of the samples was tested using a NEWARE battery testing system (BTS8.0). The voltage range for the half-cell test was 0.01-3.0 V vs. Na / Na. + The current ranges from 30 to 600 mA / g.

[0069] The hard carbon materials prepared in Examples 1, 4, 5, and 6 were applied to sodium battery tests, and the first charge-discharge curves are shown below. Figure 2 As shown, from Figure 2 It can be seen that the charge / discharge specific capacities are 491.73 / 346.59 mAh g, respectively. -1 413.78 / 300.12 mAh g -1 369.74 / 286.77 mAh g -1 286.14 / 232.38 mAh g -1 It is evident that the prepared hard carbon material exhibits optimal electrochemical performance when the mass ratio of commercial hard carbon to boric acid is 10:1.

[0070] Figure 3 The results of rate performance tests of the hard carbon materials used in Examples 1, 9, 10, and Comparative Example 1 in sodium batteries are as follows: Figure 3It can be seen that the hard carbon materials prepared in Examples 1, 9 and 10 have better electrochemical performance than Comparative Example 1 at current densities of 30 mA / g, 60 mA / g, 150 mA / g, 300 mA / g and 600 mA / g. Example 1 has better rate performance compared with Joule heating at low temperature and high temperature and tube furnace heating. Under high current, Example 10 and Comparative Example 1 have a greater decrease in specific capacity due to smaller interlayer spacing.

[0071] Figure 4 The results of constant current charge-discharge cycle tests at a current density of 1C were obtained for the application of hard carbon materials in Examples 1, 9, 10, and Comparative Example 1 in sodium batteries. Figure 4 It can be seen that Example 1 has the best long-cycle performance, while Example 10 and Comparative Example 1 are severely graphitized, and their specific capacity decreases significantly under high current density.

[0072] Figure 5 The first charge-discharge curves for Example 1 and Comparative Example 1 are shown below at a current density of 100 mA / g, with charge-discharge capacities of 491.73 / 346.59 mAh / g and 471.55 / 281.12 mAh / g, respectively. It can be seen that the Joule heating method has a higher reversible charge-discharge capacity and a higher initial coulombic efficiency compared to traditional tube furnace heating.

[0073] Figure 6 The first charge-discharge curves for Example 2 and Comparative Example 2 are shown below at a current density of 100 mA / g, with charge-discharge capacities of 443.13 / 368.24 mAh / g and 433.58 / 319.15 mAh / g, respectively. It can be seen that the Joule heating method has a higher reversible charge-discharge capacity and a higher initial coulombic efficiency compared to traditional tube furnace heating.

[0074] Figure 7 The first charge-discharge curves for Example 3 and Comparative Example 3 at a current density of 100 mA / g are shown, with charge-discharge capacities of 590 / 429.54 mAh / g and 457.12 / 312.2 mAh / g, respectively. It can be seen that the Joule heating method has a higher reversible charge-discharge capacity and a higher initial coulombic efficiency compared to traditional tube furnace heating.

[0075] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for preparing a heteroatom-doped hard carbon material, characterized in that, The process includes the following steps: mixing commercial hard carbon with a compound containing heteroatoms in a solvent to prepare a first mixture; The first mixture is sintered using Joule heating technology to prepare the hard carbon material.

2. The method for preparing hard carbon material according to claim 1, characterized in that, The reaction conditions for Joule heating are: heating rate of 50℃ / s to 100℃ / s, holding temperature of 800℃ to 1800℃, and holding time of 5s to 60s.

3. The method for preparing hard carbon material according to claim 2, characterized in that, The Joule heating reaction conditions are: heating rate of 80℃ / s~100℃ / s, holding temperature of 1200℃~1500℃, and holding time of 5s~20s.

4. The method for preparing hard carbon material according to any one of claims 1 to 3, characterized in that, The mass ratio of the heteroatom-containing compound to commercial hard carbon is (0.1~4):

20.

5. The method for preparing hard carbon material according to any one of claims 1 to 3, characterized in that, The sources of the heteroatom-containing compounds include one or more of the following: boron, phosphorus, nitrogen, sulfur, fluorine, and nickel.

6. The method for preparing hard carbon material according to claim 5, characterized in that, The boron source includes one or more of boric acid, trimethyl borate, and triphenylboron; and / or, The phosphorus source includes one or more of phosphoric acid, polyphosphoric acid, ammonium phosphate, diammonium hydrogen phosphate, triphenyl phosphate, and triethyl phosphate; and / or, The nitrogen source includes one or more of urea, melamine, dicyandiamide, ethylenediamine, polyethyleneimine, polyacrylonitrile, polyaniline, imidazole, pyridine, and ethylenediaminetetraacetic acid; and / or, The sulfur source includes one or more of dimethyl sulfoxide, thiourea, aminosulfonic acid, p-toluenesulfonic acid, ferric ammonium sulfate, and thiophene; and / or, The fluorine source includes one or more of polytetrafluoroethylene, ammonium fluoride, sodium tetrafluoroborate, and polyvinylidene fluoride; and / or, The nickel source includes one or more of nickel acetate, nickel oxalate, nickel citrate, nickel acetylacetone, nickel nitrate, nickel chloride, and nickel sulfate.

7. The method for preparing hard carbon material according to any one of claims 1 to 3, characterized in that, The solvent includes one or more of water, anhydrous ethanol, N-methylpyrrolidone, tetrahydrofuran, N,N-dimethylformamide, acetone, and acetonitrile.

8. A heteroatom-doped hard carbon material, characterized in that, The hard carbon material is prepared by the preparation method according to any one of claims 1 to 7.

9. A negative electrode material, characterized in that, The negative electrode material includes the heteroatom-doped hard carbon material as described in claim 8.

10. A sodium-ion battery, characterized in that, The negative electrode of the sodium-ion battery comprises the negative electrode material as described in claim 9.

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