Pre-lithiated silicon-oxygen negative electrode material and preparation method and use thereof

Abstract

The application provides a pre-lithiated silicon-oxygen negative electrode material and a preparation method and application thereof. The preparation method comprises the following steps: mixing a lithium source, a solvent and a silicon-oxygen material to precipitate lithium, pre-lithiation, carbon coating, and obtaining the pre-lithiated silicon-oxygen negative electrode material; wherein the chemical formula of the lithium source is Li x MH y , the chemical formula of the solvent is MH x+y , M comprises any one or a combination of at least two of C, N, S or F, x>0, and y>=0. The application realizes uniform dissolution of the lithium source by selecting a lithium source containing a nonmetal and a solvent containing the same nonmetal, realizes stable existence of the solute in the solution, reduces side reactions, uniformly disperses the lithium source on the surface of the silicon-oxygen material, and improves the initial efficiency of the silicon-oxygen negative electrode material.

Description

Technical Field

[0001] The present invention belongs to the technical field of negative electrode materials and relates to a pre-lithiation silicon oxide negative electrode material and a preparation method and application thereof. Background Art

[0002] Lithium-ion batteries have extensive applications in the new energy sector. Graphite, the most widely used anode material in lithium-ion batteries, boasts a stable voltage platform and long-cycle stability. However, its theoretical capacity is only 372 mAh / g, which cannot meet the demand for high-energy-density energy storage. Silicon-based anode materials, with their ultra-high specific capacity, hold great potential for future development. However, pure silicon materials experience significant volume expansion. Silicon oxide materials, due to their unique structural properties, can mitigate this expansion issue to a certain extent. Silicon oxide materials primarily consist of silicon nanocrystals dispersed within silicon dioxide. During the initial charge and discharge process, silicon dioxide consumes lithium salts, reducing the material's initial efficiency. Therefore, improving the initial efficiency of silicon oxide materials is crucial. Lithium pre-doping technology allows for the pre-reaction of lithium with silicon dioxide during initial processing, forming lithium silicate salts. This reduces the irreversible lithium salt consumption during the initial discharge of the battery during cycling. However, lithium metal is chemically active, and lithium and its compounds typically need to be reduced in size to improve reaction uniformity. However, the processing and use of lithium and its compounds in nanoscale form is often difficult and dangerous. Therefore, developing a method to uniformly disperse a lithium source at a microscopic size on a silicon-oxygen surface is of great significance for the preparation of high-efficiency silicon-oxygen anode materials.

[0003] US7776473B discloses grinding SiO by high energy ball grinding method. x powder and active lithium powder to carry out SiO x Pre-lithiation was successfully used to reduce the irreversible capacity loss from 35% to 15%. However, the results obtained by the method in this document are insufficient to meet the properties required for commercial anode materials. There is still a need to reduce the irreversible capacity loss in the first cycle and improve the cycling performance.

[0004] CN111900368A discloses a silicon oxide negative electrode material. Silicon oxide is first mixed with a lithium source and held at 300-700°C to obtain pre-lithiated silicon oxide. The pre-lithiated silicon oxide is then placed in a rotary kiln and carbon-coated using vapor deposition to obtain a pre-lithiated silicon oxide / carbon composite material. Finally, the pre-lithiated silicon oxide is mixed with a metal oxide so that the metal oxide is evenly coated on the surface of the silicon oxide / carbon composite material. This document only regulates the proportion of Li2Si2O5 by adjusting the type and amount of the lithium source. However, the water-insoluble Li2Si2O5 and the water-soluble Li2SiO3 are completely mixed. In the silicon oxide material, the Li2SiO3 remains exposed on the surface of the silicon oxide material, resulting in a high pH value during homogenization. Although a metal oxide layer is coated on the outermost layer of the carbon layer, this significantly reduces the conductivity of the carbon layer, defeating the purpose of the carbon coating.

[0005] Therefore, how to improve the initial efficiency of silicon-oxygen negative electrode materials is a technical problem that needs to be solved urgently. Summary of the Invention

[0006] In response to the shortcomings of the prior art, the present invention aims to provide a pre-lithiated silicon-oxygen anode material, its preparation method, and its use. By selecting a non-metallic lithium source and mixing it with a solvent containing the same non-metallic substance, the present invention achieves uniform dissolution of the lithium source, while also ensuring the stable presence of the solute in the solution and reducing side reactions. The lithium source is evenly dispersed on the surface of the silicon-oxygen material, enhancing the initial efficiency of the silicon-oxygen anode material.

[0007] To achieve this object, the present invention adopts the following technical solutions:

[0008] In a first aspect, the present invention provides a method for preparing a pre-lithiated silicon oxide negative electrode material, the preparation method comprising:

[0009] Mixing a lithium source, a solvent and a silicon oxide material to precipitate lithium, pre-lithiate, and carbon-coat to obtain the pre-lithiated silicon oxide negative electrode material;

[0010] Wherein, the chemical formula of the lithium source is Li x MH y , the chemical formula of the solvent is MH x+y , M includes any one of C, N, S or F or a combination of at least two, x>0, y≥0, for example, x can be 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10, and y can be 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10.

[0011] In the present invention, M in the lithium source and M in the solvent must be consistent.

[0012] In the present invention, Li x MHy and MH x+y The x and y in the .

[0013] In the present invention, the processes of pre-lithiation and carbon coating are both carried out under a protective atmosphere.

[0014] The present invention achieves uniform dissolution of the lithium source by selecting a non-metallic lithium source and mixing it with a non-metallic solvent of the same type. At the same time, it can achieve the purpose of stable existence of the solute in the solution and reduce side reactions. The lithium source is evenly dispersed on the surface of the silicon oxide material, thereby improving the primary efficiency of the silicon oxide negative electrode material.

[0015] In the present invention, the lithium source and the solution are similarly compatible, so that the lithium source can be well dissolved, the solute can be stably present in the solution, and the side reactions can be reduced. In addition, the lithium source can be evenly dispersed on the surface of the silicon oxide material. By mixing and precipitating lithium, the lithium salt can be evenly precipitated on the surface of the silicon oxide particles and embedded and coated on their surface.

[0016] In the present invention, the lithium source has the following differences compared with ordinary lithium metal: the lithium element in the lithium source is non-elemental lithium, has good dispersibility, and can be dispersed in a specific solvent according to the principle of like dissolves like, which is more conducive to the dispersion of the lithium source and avoids the concentration of reaction heat and uneven reaction caused by the aggregation of the lithium source. The non-elemental lithium is in the same state as the lithium element in the product, and the reaction is mild, avoiding the side reactions caused by redox and the reaction heat generated, as well as other secondary reactions generated by the reaction heat, which is more conducive to the mild reaction of the lithium source and the control of the crystal structure of the silicon oxide material.

[0017] Preferably, when M is C, the lithium source includes any one of LiCH3, Li2CH2, Li3CH or Li4C, or a combination of at least two thereof, and the solvent includes CH4.

[0018] Preferably, when M is N, the lithium source includes any one of LiNH2, Li2NH or Li3N, or a combination of at least two thereof, and the solvent includes NH3.

[0019] Preferably, when M is S, the lithium source includes any one of LiHS, Li2S or Li2S2 or a combination of at least two thereof, and the solvent includes H2S and / or H2S2.

[0020] Preferably, when M is F, the lithium source includes LiF, and the solvent includes HF.

[0021] Preferably, M is N.

[0022] In the present invention, when M in the lithium source is N, the safety, economy, and operability of the lithium source and its similar compatible solvent can be better achieved, providing the possibility for industrial scale-up. In addition, no impurities remain after the reaction, and the solvent can be easily recovered or processed.

[0023] Preferably, the molar ratio of the lithium source to the solvent is 1:(1-10000), for example, 1:1, 1:100, 1:500, 1:1000, 1:3000, 1:5000, 1:8000 or 1:10000.

[0024] Preferably, the molar ratio of lithium in the lithium source to silicon in the silicon oxide material is 10:(1-200), 10:1, 10:10, 10:30, 10:50, 10:80, 10:100, 10:130, 10:150, 10:180 or 10:200, etc., preferably 10:(10-100).

[0025] Preferably, the median particle size of the silicon oxide material is 0.5 to 50 μm, for example, 0.5 μm, 1 μm, 5 μm, 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm or 50 μm.

[0026] Preferably, the time for mixed lithium deposition is 0.5 to 10 h, for example, 0.5 h, 1 h, 2 h, 3 h, 4 h, 5 h, 6 h, 7 h, 8 h, 9 h or 10 h.

[0027] Preferably, the mixed lithium deposition method includes lithium deposition by increasing temperature and / or lithium deposition by decreasing pressure, preferably lithium deposition by decreasing pressure.

[0028] In the present invention, the method of lithium precipitation by pressure reduction is selected, which can efficiently, safely and conveniently separate the solvent and solute. Moreover, lithium precipitation by pressure reduction can avoid solute agglomeration or side reactions during the separation process.

[0029] Preferably, in the temperature-raising lithium precipitation, the temperature after heating is -85 to 200°C, for example, -85°C, -80°C, -75°C, -70°C, -65°C, -60°C, -55°C, -50°C, -40°C, -30°C, -20°C, -10°C, 0°C, 30°C, 50°C, 80°C, 100°C, 130°C, 150°C, 180°C or 200°C, etc.

[0030] In the present invention, the temperature for heating and lithium deposition depends on the boiling point of the solvent. The temperature for heating and lithium deposition should be higher than the boiling point of the solvent.

[0031] Preferably, in the pressure reduction lithium precipitation, the pressure after pressure reduction is 0.0001-5 MPa, for example, 0.0001 MPa, 0.001 MPa, 0.01 MPa, 0.05 MPa, 0.08 MPa, 0.1 MPa, 0.5 MPa, 1 MPa, 2 MPa, 3 MPa, 4 MPa or 5 MPa, etc., preferably 0.05-0.5 MPa.

[0032] In the present invention, if the pressure after decompression and lithium precipitation is too high, the solvent will evaporate slowly and the processing time will be increased; if the pressure after decompression and lithium precipitation is too low, it will be detrimental to the stability of the reaction and will easily cause the loss of material entrained by the solvent.

[0033] Preferably, the pre-lithiation temperature is 100-600°C, for example, 100°C, 200°C, 300°C, 400°C, 500°C or 600°C.

[0034] Preferably, the pre-lithiation time is 1 to 10 h, for example, 1 h, 2 h, 3 h, 4 h, 5 h, 6 h, 7 h, 8 h, 9 h or 10 h.

[0035] Preferably, the temperature of the carbon coating is 600-1200°C, for example, 600°C, 700°C, 800°C, 900°C, 1000°C, 1100°C or 1200°C.

[0036] Preferably, the carbon coating time is 1 to 10 hours, for example, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours or 10 hours.

[0037] Preferably, the carbon coating method comprises vapor deposition carbon coating.

[0038] Preferably, the carbon source in the vapor-deposited carbon coating includes any one of acetylene, ethylene, propylene, propane, ethane, methane, benzene vapor, toluene vapor or acetonitrile vapor, or a combination of at least two thereof.

[0039] As a preferred technical solution, the preparation method includes:

[0040] A lithium source, a solvent, and a silicon oxide material having a median particle size of 0.5 to 50 μm are mixed to precipitate lithium for 0.5 to 10 hours, the pressure is reduced to 0.05 to 0.5 MPa during the mixed lithium precipitation process to achieve mixed lithium precipitation, a pre-lithiation is performed at 100 to 600° C. for 1 to 10 hours, and a vapor deposition carbon coating is performed at 600 to 1200° C. for 1 to 10 hours to obtain the pre-lithiation silicon oxide negative electrode material;

[0041] Wherein, the chemical formula of the lithium source is Li x MH y , the chemical formula of the solvent is MH x+y, M includes any one or a combination of at least two of C, N, S or F, x>0, y≥0; the molar ratio of the lithium source to the solvent is 1:(1~10000); the molar ratio of lithium in the lithium source to silicon in the silicon oxide material is 10:(1~200).

[0042] In a second aspect, the present invention provides a pre-lithiated silicon oxide negative electrode material, wherein the pre-lithiated silicon oxide negative electrode material is prepared by the preparation method of the pre-lithiated silicon oxide negative electrode material as described in the first aspect.

[0043] In a third aspect, the present invention further provides a lithium-ion battery, comprising the pre-lithiated silicon oxide negative electrode material as described in the second aspect.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] The present invention achieves uniform dissolution of the lithium source by selecting a non-metallic lithium source and mixing it with a non-metallic solvent of the same type. At the same time, it can achieve the purpose of stable existence of the solute in the solution and reduce side reactions. The lithium source is evenly dispersed on the surface of the silicon-oxygen material, improving the initial efficiency of the silicon-oxygen negative electrode material. The battery obtained from the negative electrode material provided by the present invention can achieve an initial efficiency of more than 79.5% at 0.1C when using the temperature increase lithium precipitation method, and can achieve an initial efficiency of more than 83.6% at 0.1C when using the pressure reduction lithium precipitation method. Under the same negative electrode material, the initial efficiency improved by the pressure reduction lithium precipitation method is more than 1.1% higher than the initial efficiency of the temperature increase lithium precipitation method. DETAILED DESCRIPTION

[0046] The technical solutions of the present invention are further illustrated by specific examples below. Those skilled in the art should understand that the examples are only for helping to understand the present invention and should not be regarded as specific limitations of the present invention.

[0047] Example 1

[0048] This embodiment provides a method for preparing a pre-lithiated silicon oxide negative electrode material, and the preparation method is as follows:

[0049] (1) Lithium nitride was dissolved in liquid ammonia (the molar ratio of lithium nitride to liquid ammonia was 1:500), and then silicon oxide with a median particle size of 10 μm was added and stirred for 1 hour (the molar ratio of lithium in lithium nitride to silicon in silicon oxide was 10:10). The mixture was heated to -30°C and stirred for 5 hours to precipitate the lithium source on the surface of the silicon oxide material and uniformly coat it, thereby obtaining particles to be pre-lithiated;

[0050] (2) The particles to be pre-lithiated are transferred to a reactor, and pre-lithiated at a pre-lithiation temperature of 500°C for 5 hours under a nitrogen atmosphere. Then, acetylene is used as a carbon source and carbon coating is continued at 800°C for 3 hours under a nitrogen atmosphere to obtain the pre-lithiated silicon oxide negative electrode material.

[0051] Example 2

[0052] This embodiment provides a method for preparing a pre-lithiated silicon oxide negative electrode material, and the preparation method is as follows:

[0053] (1) Methyl lithium (LiCH3) was dissolved in liquid methane (the molar ratio of lithium carbide to liquid methane was 1:1000), and then silicon oxide material (SiO 0.95 ) and stirring for 0.5 h (the molar ratio of lithium in the methyllithium to silicon in the silicon oxide material is 10:20), and stirring is continued at 5 MPa and -85°C for 8 h to precipitate the lithium source on the surface of the silicon oxide material and uniformly coat it, thereby obtaining particles to be pre-lithiated;

[0054] (2) The particles to be pre-lithiated are transferred to a reactor, and pre-lithiated at a pre-lithiation temperature of 200°C for 3 hours under an argon atmosphere. Then, ethylene is used as a carbon source and carbon coating is continued at 1000°C for 5 hours under an argon atmosphere to obtain the pre-lithiated silicon oxide negative electrode material.

[0055] Example 3

[0056] This embodiment provides a method for preparing a pre-lithiated silicon oxide negative electrode material, and the preparation method is as follows:

[0057] (1) Lithium nitride was dissolved in liquid ammonia (the molar ratio of lithium nitride to liquid ammonia was 1:2000), and then silicon oxide material (SiO 1.05 ) and stirring for 1 h (the molar ratio of lithium in lithium nitride to silicon in silicon oxide is 10:50), heating to -30°C and continuing stirring for 5 h to precipitate the lithium source on the surface of the silicon oxide material and uniformly coat it, thereby obtaining particles to be pre-lithiated;

[0058] (2) The particles to be pre-lithiated are transferred to a reactor, and pre-lithiated at a pre-lithiation temperature of 500°C for 2 hours under a nitrogen atmosphere. Then, acetylene is used as a carbon source and carbon coating is continued at 950°C for 3 hours under a nitrogen atmosphere to obtain the pre-lithiated silicon oxide negative electrode material.

[0059] Example 4

[0060] The difference between this embodiment and embodiment 1 is that in step (1) of this embodiment, the temperature increase operation is replaced by reducing the pressure to 0.1 MPa (i.e., releasing air through a pressure reducing valve).

[0061] The rest of the preparation methods and parameters were the same as those in Example 1.

[0062] Example 5

[0063] The difference between this embodiment and embodiment 2 is that in step (1) of this embodiment, the temperature increase operation is replaced by reducing the pressure to 0.1 MPa.

[0064] The rest of the preparation methods and parameters were the same as those in Example 1.

[0065] Comparative Example 1

[0066] The difference between this comparative example and Example 1 is that the solvent in step (1) of this example is ethanol.

[0067] The rest of the preparation methods and parameters were the same as those in Example 1.

[0068] Comparative Example 2

[0069] The difference between this comparative example and Example 1 is that in this comparative example, the silicon monoxide material is not pre-lithiated, and the carbon coating process is directly performed.

[0070] The rest of the preparation methods and parameters were the same as those in Example 1.

[0071] Electrochemical test: Test of material capacity and first effect: The negative electrode materials obtained in Examples 1-5 and Comparative Examples 1-2 were evenly mixed with SBR, CMC, and SP in a ratio of 85:3.2:1.8:10, coated on copper foil, dried, rolled, and cut to prepare pole pieces with a diameter of 12 mm, which were assembled with metal lithium sheets into button batteries, wherein the electrolyte was a conventional lithium-ion battery electrolyte and the diaphragm was a PP diaphragm. The electrochemical performance test was carried out by conventional battery charge and discharge on a blue electric tester. The capacity of the negative electrode material is the half-cell delithiation mass specific capacity measured at a rate of 0.1C. The results are shown in Table 1.

[0072] Table 1

[0073]

[0074]

[0075] From the data results of Examples 1 and 4, and Examples 2 and 5, it can be seen that the method of pressure reduction lithium precipitation is used to precipitate the lithium source from the surface of the silicon source material and uniformly coat the surface of the silicon oxide material, which is conducive to efficient, safe and convenient solvent solute separation. In addition, pressure reduction lithium precipitation can avoid solute agglomeration or side reactions during the separation process, and has the advantage of efficient pre-lithiation.

[0076] From the data results of Example 1 and Comparative Example 1, it can be seen that if a non-metallic element solvent different from the non-metallic element in the lithium source is selected, it is difficult to achieve the expected pre-lithium effect.

[0077] From the data results of Example 1 and Comparative Example 2, it can be seen that if the silicon-oxygen negative electrode material is not pre-lithiated and is simply carbon-coated, its first efficiency will be relatively low.

[0078] In summary, the present invention achieves uniform dissolution of the lithium source by selecting a non-metallic lithium source and mixing it with a non-metallic solvent of the same type, and at the same time can achieve the purpose of stable existence of the solute in the solution and reduction of side reactions. The lithium source is evenly dispersed on the surface of the silicon oxide material, which improves the first efficiency of the silicon oxide negative electrode material. The battery obtained from the negative electrode material provided by the present invention can achieve a first efficiency of more than 79.5% at 0.1C when using the temperature increase lithium precipitation method, and can achieve a first efficiency of more than 83.6% at 0.1C when using the pressure reduction lithium precipitation method. Under the same negative electrode material, the first efficiency improved by the pressure reduction lithium precipitation method is more than 1.1% higher than the first efficiency of the temperature increase lithium precipitation method.

[0079] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for preparing a pre-lithiated silicon oxide negative electrode material, characterized in that: The preparation method comprises: Mixing a lithium source, a solvent and a silicon oxide material to precipitate lithium, pre-lithiate, and carbon-coat to obtain the pre-lithiated silicon oxide negative electrode material; Wherein, the chemical formula of the lithium source is Li x MH y , the chemical formula of the solvent is MH x+y , M includes any one of C, N, S or F or a combination of at least two, x>0, y≥0.

2. The method for preparing a pre-lithiated silicon oxide negative electrode material according to claim 1, wherein: When M is C, the lithium source includes any one of LiCH3, Li2CH2, Li3CH or Li4C, or a combination of at least two thereof, and the solvent includes CH4.

3. The method for preparing a pre-lithiated silicon oxide negative electrode material according to claim 1, wherein: When M is N, the lithium source includes any one of LiNH2, Li2NH or Li3N or a combination of at least two thereof, and the solvent includes NH3.

4. The method for preparing a pre-lithiated silicon oxide negative electrode material according to claim 1, wherein: When M is S, the lithium source includes any one of LiHS, Li2S or Li2S2 or a combination of at least two thereof, and the solvent includes H2S and / or H2S2.

5. The method for preparing a pre-lithiated silicon oxide negative electrode material according to claim 1, wherein: When M is F, the lithium source includes LiF, and the solvent includes HF.

6. The method for preparing a pre-lithiated silicon oxide negative electrode material according to claim 1, wherein: The median particle size of the silicon oxide material is 0.5 to 50 μm.

7. The method for preparing a pre-lithiated silicon oxide negative electrode material according to claim 1, wherein: The molar ratio of the lithium source to the solvent is 1:(1-10000).

8. The method for preparing a pre-lithiated silicon oxide negative electrode material according to claim 1, wherein: The molar ratio of lithium in the lithium source to silicon in the silicon oxide material is 10:(1-200).

9. The method for preparing a pre-lithiated silicon oxide negative electrode material according to claim 8, wherein: The molar ratio of lithium in the lithium source to silicon in the silicon oxide material is 10:(10-100).

10. The method for preparing a pre-lithiated silicon oxide negative electrode material according to claim 1, wherein: The time for mixed lithium deposition is 0.5 to 10 hours.

11. The method for preparing a pre-lithiated silicon oxide negative electrode material according to claim 1, wherein: The mixed lithium deposition method includes lithium deposition by increasing temperature and / or lithium deposition by decreasing pressure.

12. The method for preparing a pre-lithiated silicon oxide negative electrode material according to claim 11, wherein: The mixed lithium deposition method is pressure-reducing lithium deposition.

13. The method for preparing a pre-lithiated silicon oxide negative electrode material according to claim 11, wherein: In the above-mentioned lithium deposition by heating, the temperature after heating is -85 to 200°C.

14. The method for preparing a pre-lithiated silicon oxide negative electrode material according to claim 11, wherein: In the lithium precipitation by reducing pressure, the pressure after reducing pressure is 0.0001-5 MPa.

15. The method for preparing a pre-lithiated silicon oxide negative electrode material according to claim 14, characterized in that: In the lithium precipitation by reducing pressure, the pressure after reducing pressure is 0.05-0.5 MPa.

16. The method for preparing a pre-lithiated silicon oxide negative electrode material according to claim 1, wherein: The pre-lithiation temperature is 100-600°C.

17. The method for preparing a pre-lithiated silicon oxide negative electrode material according to claim 1, wherein: The pre-lithiation time is 1 to 10 hours.

18. The method for preparing a pre-lithiated silicon oxide negative electrode material according to claim 1, wherein: The carbon coating temperature is 600-1200°C.

19. The method for preparing a pre-lithiated silicon oxide negative electrode material according to claim 1, wherein: The carbon coating time is 1 to 10 hours.

20. The method for preparing a pre-lithiated silicon oxide negative electrode material according to claim 1, wherein: The carbon coating method includes vapor deposition carbon coating.

21. The method for preparing a pre-lithiated silicon oxide negative electrode material according to claim 20, wherein: The carbon source in the vapor-deposited carbon coating includes any one of acetylene, ethylene, propylene, propane, ethane, methane, benzene vapor, toluene vapor or acetonitrile vapor, or a combination of at least two thereof.

22. The method for preparing a pre-lithiated silicon oxide negative electrode material according to claim 1, wherein: The preparation method comprises: A lithium source, a solvent, and a silicon oxide material having a median particle size of 0.5 to 50 μm are mixed to precipitate lithium for 0.5 to 10 hours, the pressure is reduced to 0.05 to 0.5 MPa during the mixed lithium precipitation process to achieve mixed lithium precipitation, a pre-lithiation is performed at 100 to 600° C. for 1 to 10 hours, and a vapor deposition carbon coating is performed at 600 to 1200° C. for 1 to 10 hours to obtain the pre-lithiation silicon oxide negative electrode material; Wherein, the chemical formula of the lithium source is Li x MH y , the chemical formula of the solvent is MH x+y , M includes any one or a combination of at least two of C, N, S or F, x>0, y≥0; the molar ratio of the lithium source to the solvent is 1:(1~10000); the molar ratio of lithium in the lithium source to silicon in the silicon oxide material is 10:(1~200).

23. A pre-lithiation silicon oxide negative electrode material, characterized in that: The pre-lithiated silicon oxide negative electrode material is prepared by the preparation method of the pre-lithiated silicon oxide negative electrode material according to any one of claims 1 to 22.

24. A lithium ion battery, characterized in that: The lithium-ion battery comprises the pre-lithiated silicon-oxygen negative electrode material according to claim 23.

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