A pre-lithiation method for a silicon-based anode sheet

Abstract

The present invention discloses a method for prelithiation of a silicon-based anode sheet, comprising the following steps: S1. Wet two surfaces of the silicon-based anode sheet with a low-concentration electrolyte, attach a lithium strip to the wetted surfaces, then attach a flexible sieve cloth to the surface of the lithium strip, and then perform cold roll pressing to obtain a composite structure sheet; S2. Place the composite structure sheet in an inert atmosphere until the lithium strip has no metallic luster, then perform vacuum heating, and remove the flexible sieve cloth after heating to obtain a prelithiated silicon-based anode sheet. The present invention effectively solves the problems of low initial efficiency and poor cycle performance of mechanized prelithiation of silicon-based anodes in a low-cost manner, and reduces the technical difficulty of industrial production of high-energy-density battery cells.

Description

Technical Field

[0001] The present invention relates to the technical field of pre-lithiation of lithium-ion batteries, and particularly to a method for pre-lithiating a silicon-based anode sheet. Background Art

[0002] In recent years, the new energy industry has developed rapidly, and the research and development of materials and battery cell systems have been in full swing. The demand for the energy density of the lithium battery industry has increased year by year. From battery cells to modules, the pursuit is for extreme lightweight, but the use of positive and negative electrode material systems still remains at the level of a decade ago. Currently, among solid-state, semi-solid-state, and liquid batteries, the most popular anode material is silicon-based material. Silicon-based anodes have extremely high lithium storage capacity, theoretically up to 4200 mAh / g, and rich resources. The specific capacity of silicon monoxide can also reach more than 1400 mAh / g. It is currently the most promising material to replace graphite as the anode of the next-generation lithium-ion battery. Silicon-based anodes may be the key to improving future energy density and have become the preferred anode for current ternary high-energy density battery cells. However, the first efficiency of silicon-oxygen anodes is far lower than that of the graphite system. Even after years of deep cultivation by material manufacturers, material pre-lithiation cannot make up for the nearly 15% capacity loss. There is still a large gap in the cycling performance between high-silicon systems and the graphite system. The problem of low first efficiency of the anode still hinders the improvement of energy density, and pre-lithiation brings new hope for the improvement of the first efficiency and cycling performance of the silicon-based anode system. In recent years, the development of positive and negative electrode pre-lithiation technologies has reached a white-hot stage. Mastering pre-lithiation technology means mastering the future of high-energy density systems. Among the currently feasible pre-lithiation technologies, mechanical pre-lithiation of the anode has the highest efficiency. However, for conventional mechanical pre-lithiation methods of the anode, due to the slow ion diffusion rate of the lithium strip and low efficiency, the lithium compensation effect is poor, and there is often a problem that the pre-lithiation amount of the anode cannot reach the preset value, the improvement effect of the first efficiency is not good, and the pre-lithiation uniformity is poor and the cell consistency is poor, resulting in poor overall cycling performance. Summary of the Invention

[0003] Based on the technical problems existing in the background art, the present invention proposes a method for pre-lithiating a silicon-based anode sheet.

[0004] A method for pre-lithiating a silicon-based anode sheet proposed by the present invention includes the following steps:

[0005] S1. Wet the two surfaces of the silicon-based anode sheet with a low-concentration electrolyte, attach a lithium strip to the wetted surface, then attach a flexible sieve cloth to the surface of the lithium strip, and then perform cold roll pressing to obtain a composite structure sheet;

[0006] S2. Place the composite structure sheet in an inert atmosphere until the lithium strip has no metallic luster, then perform vacuum heating. After heating is completed, remove the flexible sieve cloth to obtain a pre-lithiated silicon-based anode sheet.

[0007] In S1, the method of wetting both surfaces of the silicon-based anode electrode sheet with a low-concentration electrolyte can adopt conventional methods, such as coating and spraying.

[0008] Preferably, in the low-concentration electrolyte, the mass concentration of the lithium salt is 2-5%. The purpose of using the low-concentration lithium salt electrolyte in the present invention is to reduce the influence on the subsequent processes, while the high-concentration electrolyte will increase polarization and affect the cycle performance.

[0009] Preferably, the low-concentration electrolyte comprises raw materials in the following mass percentages: 2-5% of lithium salt, 0-15% of fluoroethylene carbonate, and the balance being an organic solvent.

[0010] Preferably, the low-concentration electrolyte comprises raw materials in the following mass percentages: 2-5% of lithium salt, 8-15% of fluoroethylene carbonate, and the balance being an organic solvent.

[0011] Among them, the lithium salt can adopt conventional lithium salts for electrolytes. Preferably, the lithium salt is at least one of lithium perchlorate (LiClO4), lithium tetrafluoroborate (LiBF4), lithium hexafluoroarsenate (LiAsF6), lithium hexafluorophosphate (LiPF6), and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI).

[0012] Among them, the organic solvent can adopt conventional organic solvents for electrolytes. Preferably, the organic solvent is at least one of ethylene carbonate (EC), diethyl carbonate (DEC), dimethyl carbonate (DMC), and ethyl methyl carbonate (EMC).

[0013] Preferably, the dosage of the low-concentration electrolyte on a single surface of the electrode sheet is 30-50 mL / m 2 .

[0014] Preferably, the thickness of the lithium strip is 4-8 μm.

[0015] Preferably, the mesh number of the flexible sieve cloth is 100-250 meshes, and the material is polyurethane, polyester or a combination thereof.

[0016] Among them, the size of the lithium strip is larger than the size of the anode electrode sheet, and the lithium strip completely covers the anode electrode sheet.

[0017] Preferably, in S1, the pressure of the cold roll pressing is 160-200 MPa.

[0018] Preferably, in S2, the temperature of the vacuum heating is 60-75 °C, and the time ≥ 24 h.

[0019] Preferably, in S2, the time of the vacuum heating is 48-72 h.

[0020] Preferably, the silicon-based negative electrode sheet is obtained by coating a silicon-based negative electrode slurry on the surface of a negative electrode current collector, followed by drying, winding, and die-cutting; the silicon-based negative electrode slurry comprises the following raw materials in parts by mass: 10-13 parts of a silicon-carbon negative electrode material, 2-5 parts of a binder, 2-5 parts of a conductive agent, and 75-80 parts of deionized water.

[0021] In the present invention, a binder commonly used in negative electrode slurries can be used for the binder without special limitation. Preferably, the binder is a polyacrylic acid-based binder.

[0022] In the present invention, a conductive agent commonly used in negative electrode slurries can be used for the conductive agent without special limitation. Preferably, the conductive agent is carbon nanotubes, conductive carbon black, graphene, long-sized carbon tubes, or a combination thereof.

[0023] A prelithiated silicon-based negative electrode sheet is obtained by the method described above.

[0024] The beneficial effects of the present invention are as follows:

[0025] In the present invention, the surface of the silicon-based negative electrode sheet is first wetted with a low-concentration electrolyte to infiltrate the surface of the negative electrode sheet with an electrolyte containing a lithium salt, and then mechanical rolling is performed to closely fit the lithium strip with the infiltrated negative electrode sheet in contact, so that the ion diffusion is changed from the solid-solid interface of the lithium metal-negative electrode sheet to the solid-liquid interface of the lithium metal-infiltrated negative electrode sheet, thereby constructing an efficient ion transport channel, improving the depth and uniformity of mechanical prelithiation; after the self-discharge at the solid-liquid interface of the metallic lithium ends, a vacuum heating process is introduced to improve the kinetics of lithium ion insertion into the silicon oxide negative electrode, ionize the remaining outer-layer metallic lithium ions and completely introduce them into the silicon oxide, effectively improving the first efficiency of the small-particle silicon-based negative electrode. In addition, in order to overcome the problems of poor contact between some positions of the negative electrode and the lithium strip, uneven prelithiation of the large surface of the electrode sheet, and poor consistency and cycling performance of the finished battery cells caused by different lithium insertion depths of particles due to the use of a PET film as a rolling substrate or no substrate in the conventional mechanical prelithiation method, in the present invention, a flexible sieve cloth is attached to the outer surface of the lithium strip, which can provide toughness and roughness, making the fit between the lithium strip and the electrode sheet higher, so that they are more closely in contact during mechanical rolling and the prelithiation is more uniform. Through the prelithiation process of the present invention, the prelithiation amount can be controlled according to the thickness of the lithium strip, and it has the advantages of high prelithiation degree and good prelithiation uniformity. It can not only significantly improve the first efficiency of the prelithiated electrode sheet, but also the prelithiated negative electrode sheet has excellent cycling performance. The present invention effectively solves the problems of low first efficiency and poor cycling performance of the mechanized prelithiation of silicon-based negative electrodes in a low-cost manner, and reduces the technical difficulty of industrial production of high-energy-density battery cells. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a cycling performance diagram of battery cells assembled with electrode sheets prelithiated by the prelithiation methods of Example 1 and Comparative Examples 1-5 of the present invention. Detailed implementation manners

[0027] Next, the technical solution of the present invention will be described in detail through specific embodiments.

[0028] In the following embodiments and comparative examples, the flexible sieve cloth is a polyurethane sieve cloth produced by Hengshui Chiyuan Machinery Technology Co., Ltd., with a single-layer weaving process, a thickness of 0.7 - 1.2 mm, and a single-filament diameter of 0.07 mm.

[0029] Embodiment 1

[0030] Prepare a silicon-based anode electrode sheet:

[0031] Mix 13 parts by mass of silicon-carbon anode material, 1 part by mass of single-walled carbon nanotubes, and 1 part by mass of conductive carbon black evenly, then add 2 parts by mass of polyacrylic binder and 20 parts by mass of deionized water for kneading. After kneading, add 60 parts by mass of deionized water, disperse evenly at high speed, then remove bubbles under vacuum, and sieve through a 150-mesh sieve to obtain a silicon-based anode slurry;

[0032] Coat the silicon-based anode slurry on the surface of the copper foil, dry it by blowing air at 90 °C, then wind it up and die-cut it to obtain a silicon-based anode electrode sheet with a size of 126 * 96 mm.

[0033] The pre-lithiation method for the silicon-based anode electrode sheet includes:

[0034] S1. Uniformly spray a low-concentration electrolyte on both surfaces of the silicon-based anode electrode sheet for wetting, and the spraying amount per single surface is 40 mL / m 2 , attach a lithium strip with a size of 130 * 100 mm and a thickness of 5 μm to the wetted surface, then attach a flexible sieve cloth to the surface of the lithium strip, and then perform cold roll pressing. The diameter of the roll is 1.5 meters, and the pressure is 180 MPa to obtain a composite structure electrode sheet; among them, the preparation method of the low-concentration electrolyte is: mix 8 parts by mass of fluoroethylene carbonate and 88 parts by mass of diethyl carbonate, and then add 4 parts by mass of lithium hexafluorophosphate and stir well until dissolved to obtain;

[0035] S2. Place the composite structure electrode sheet in a nitrogen atmosphere until the lithium strip has no metallic luster, and then perform vacuum heating at 70 °C for 48 h. After heating, remove the flexible sieve cloth to obtain a pre-lithiated silicon-based anode electrode sheet.

[0036] Embodiment 2

[0037] Prepare a silicon-based anode electrode sheet:

[0038] Mix 10 parts by mass of silicon-carbon anode material, 2 parts by mass of single-walled carbon nanotubes, and 1 part by mass of conductive carbon black evenly, then add 3 parts by mass of polyacrylic acid binder and 20 parts by mass of deionized water for kneading. After kneading, add 60 parts by mass of deionized water, disperse evenly at high speed, then remove bubbles under vacuum, and screen through a 150-mesh sieve to obtain a silicon-based anode slurry;

[0039] Coat the silicon-based anode slurry on the surface of copper foil, dry it by blowing air at 90 °C, then wind it up and die-cut to obtain a silicon-based anode plate with a size of 126*96 mm.

[0040] A pre-lithiation method for a silicon-based anode plate includes:

[0041] S1. Evenly spray a low-concentration electrolyte on the two surfaces of the silicon-based anode plate for wetting. The spraying amount for a single surface is 30 mL / m 2 , attach a lithium strip with a size of 130*100 mm and a thickness of 6 μm to the wetted surface, then attach a flexible sieve cloth to the surface of the lithium strip, and then perform cold roll pressing. The diameter of the press roll is 1.5 m and the pressure is 160 MPa to obtain a composite structure plate; among them, the preparation method of the low-concentration electrolyte is: add 2 parts by mass of lithium hexafluorophosphate to 98 parts by mass of diethyl carbonate and stir well until dissolved;

[0042] S2. Place the composite structure plate in a nitrogen atmosphere until the lithium strip has no metallic luster, then heat it under vacuum at 60 °C for 24 h. After heating, remove the flexible sieve cloth to obtain a pre-lithiated silicon-based anode plate.

[0043] Example 3

[0044] Prepare a silicon-based anode plate:

[0045] Mix 12 parts by mass of silicon-carbon anode material, 3 parts by mass of single-walled carbon nanotubes, and 2 parts by mass of conductive carbon black evenly, then add 5 parts by mass of polyacrylic acid binder and 25 parts by mass of deionized water for kneading. After kneading, add 50 parts by mass of deionized water, disperse evenly at high speed, then remove bubbles under vacuum, and screen through a 150-mesh sieve to obtain a silicon-based anode slurry;

[0046] Coat the silicon-based anode slurry on the surface of copper foil, dry it by blowing air at 90 °C, then wind it up and die-cut to obtain a silicon-based anode plate with a size of 126*96 mm.

[0047] A pre-lithiation method for a silicon-based anode plate includes:

[0048] S1. Evenly spray a low-concentration electrolyte on the two surfaces of the silicon-based anode plate for wetting. The spraying amount for a single surface is 50 mL / m 2, a lithium belt with a size of 130*100mm and a thickness of 8μm is bonded to the wetted surface, and then a flexible screen cloth is bonded to the surface of the lithium belt, and then cold rolling is performed, the roller diameter is 1.5 meters, and the pressure is 200MPa, to obtain a composite structure electrode; wherein, the preparation method of the low-concentration electrolyte is: after mixing 15 parts by mass of fluoroethylene carbonate and 80 parts by mass of diethyl carbonate, 5 parts by mass of lithium hexafluorophosphate are added and stirred thoroughly until dissolved, to obtain;

[0049] S2. Place the composite structure electrode in a nitrogen atmosphere until the lithium strip has no metallic luster, and then vacuum heat it at 75°C for 72 hours. After heating, remove the flexible screen cloth to obtain a pre-lithium silicon-based negative electrode electrode.

[0050] Comparative Example 1

[0051] Preparation of silicon-based negative electrode sheet:

[0052] 13 parts by mass of silicon-carbon negative electrode material, 1 part by mass of single-walled carbon nanotubes, and 1 part by mass of conductive carbon black were mixed evenly, and then 2 parts by mass of polyacrylic acid binder and 20 parts by mass of deionized water were added for kneading, and after kneading, 60 parts by mass of deionized water were added, and the mixture was evenly dispersed at high speed, and then vacuum-defoamed, and sieved with a 150-mesh screen to obtain a silicon-based negative electrode slurry;

[0053] The silicon-based negative electrode slurry was coated on the surface of the copper foil, dried by air blast at 90°C, rolled up, and die-cut to obtain a silicon-based negative electrode sheet with a size of 126*96mm.

[0054] The pre-lithiation method of silicon-based negative electrode plate includes:

[0055] S1. A lithium strip with a size of 130*100 mm and a thickness of 5 μm is bonded to the two surfaces of the silicon-based negative electrode plate, and a flexible screen cloth is bonded to the surface of the lithium strip, and then cold rolling is performed with a roller diameter of 1.5 meters and a pressure of 180 MPa to obtain a composite structure plate;

[0056] S2. Place the composite structure electrode in a nitrogen atmosphere until the lithium strip has no metallic luster, and then vacuum heat it at 70°C for 48 hours. After heating, remove the flexible screen cloth to obtain a pre-lithium silicon-based negative electrode electrode.

[0057] Comparative Example 2

[0058] Preparation of silicon-based negative electrode:

[0059] 13 parts by mass of silicon-carbon negative electrode material, 1 part by mass of single-walled carbon nanotubes, and 1 part by mass of conductive carbon black were mixed evenly, and then 2 parts by mass of polyacrylic acid binder and 20 parts by mass of deionized water were added for kneading, and after kneading, 60 parts by mass of deionized water were added, and the mixture was evenly dispersed at high speed, and then vacuum-defoamed, and sieved with a 150-mesh screen to obtain a silicon-based negative electrode slurry;

[0060] The silicon-based anode slurry is coated on the surface of the copper foil, dried by blowing air at 90 °C, wound up, and die-cut to obtain a silicon-based anode sheet with a size of 126*96 mm.

[0061] A pre-lithiation method for a silicon-based anode sheet includes:

[0062] S1. Uniformly spray a low-concentration electrolyte on both surfaces of the silicon-based anode sheet for wetting, and the spraying amount for a single surface is 40 mL / m 2 , attach a lithium strip with a size of 130*100 mm and a thickness of 5 μm to the wetted surface, and then perform cold roll pressing. The diameter of the roll is 1.5 m and the pressure is 180 MPa to obtain a composite structure sheet; among them, the preparation method of the low-concentration electrolyte is: mix 8 parts by mass of fluoroethylene carbonate with 88 parts by mass of diethyl carbonate, and then add 4 parts by mass of lithium hexafluorophosphate and stir well until dissolved, that is, obtain;

[0063] S2. Place the composite structure sheet in a nitrogen atmosphere until the lithium strip has no metallic luster, and then perform vacuum heating at 70 °C for 48 h to obtain a pre-lithiated silicon-based anode sheet.

[0064] Comparative Example 3

[0065] Prepare a silicon-based anode sheet:

[0066] Mix 13 parts by mass of silicon-carbon anode material, 1 part by mass of single-walled carbon nanotubes, and 1 part by mass of conductive carbon black evenly, then add 2 parts by mass of polyacrylic acid binder and 20 parts by mass of deionized water for kneading. After kneading, add 60 parts by mass of deionized water, disperse evenly at high speed, then remove bubbles under vacuum, and sieve through a 150-mesh sieve to obtain a silicon-based anode slurry;

[0067] The silicon-based anode slurry is coated on the surface of the copper foil, dried by blowing air at 90 °C, wound up, and die-cut to obtain a silicon-based anode sheet with a size of 126*96 mm.

[0068] A pre-lithiation method for a silicon-based anode sheet includes:

[0069] S1. Uniformly spray a low-concentration electrolyte on both surfaces of the silicon-based anode sheet for wetting, and the spraying amount for a single surface is 40 mL / m 2 , attach a lithium strip with a size of 130*100 mm and a thickness of 5 μm to the wetted surface, then attach a flexible sieve cloth to the surface of the lithium strip, and then perform cold roll pressing. The diameter of the roll is 1.5 m and the pressure is 180 MPa to obtain a composite structure sheet; among them, the preparation method of the low-concentration electrolyte is: mix 8 parts by mass of fluoroethylene carbonate with 88 parts by mass of diethyl carbonate, and then add 4 parts by mass of lithium hexafluorophosphate and stir well until dissolved, that is, obtain;

[0070] S2. Place the composite structure electrode in a nitrogen atmosphere until the lithium strip loses its metallic luster, and then remove the flexible sieve cloth to obtain the pre-lithiated silicon-based anode electrode.

[0071] Comparative Example 4

[0072] Comparative Example 4 is a conventional mechanical pre-lithiation method, including:

[0073] Prepare a silicon-based anode electrode:

[0074] Mix 13 parts by mass of silicon-carbon anode material, 1 part by mass of single-walled carbon nanotubes, and 1 part by mass of conductive carbon black evenly, then add 2 parts by mass of polyacrylic binder and 20 parts by mass of deionized water for kneading. After kneading, add 60 parts by mass of deionized water, disperse evenly at high speed, then remove bubbles under vacuum, and sieve through a 150-mesh sieve to obtain a silicon-based anode slurry;

[0075] Coat the silicon-based anode slurry on the surface of the copper foil, dry it by blowing air at 90 °C, wind it up, and die-cut it to obtain a silicon-based anode electrode with a size of 126*96 mm.

[0076] The pre-lithiation method of the silicon-based anode electrode includes:

[0077] S1. Attach lithium strips with a size of 130*100 mm and a thickness of 5 μm to both surfaces of the silicon-based anode electrode, and then heat and roll at 70 °C. The diameter of the rolling roller is 1.5 m, and the pressure is 180 MPa to obtain a composite structure electrode;

[0078] S2. Place the composite structure electrode in a nitrogen atmosphere until the lithium strip loses its metallic luster to obtain the pre-lithiated silicon-based anode electrode.

[0079] Comparative Example 5

[0080] Comparative Example 5 is an electrode without pre-lithiation treatment, specifically as follows:

[0081] Prepare a silicon-based anode electrode:

[0082] Mix 13 parts by mass of silicon-carbon anode material, 1 part by mass of single-walled carbon nanotubes, and 1 part by mass of conductive carbon black evenly, then add 2 parts by mass of polyacrylic binder and 20 parts by mass of deionized water for kneading. After kneading, add 60 parts by mass of deionized water, disperse evenly at high speed, then remove bubbles under vacuum, and sieve through a 150-mesh sieve to obtain a silicon-based anode slurry;

[0083] Coat the silicon-based anode slurry on the surface of the copper foil, dry it by blowing air at 90 °C, wind it up, and die-cut it to obtain a silicon-based anode electrode with a size of 126*96 mm.

[0084] Test Example

[0085] The pre-lithiated electrode sheets of Example 1 and Comparative Examples 1-4 were made into lithium button batteries and discharged against lithium, and the pre-lithiation amount was calculated (the theoretical lithium compensation amount of a 5-μm lithium strip is 0.9658 Ah). The results are shown in Table 1:

[0086] Table 1

[0087] Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Pre-lithium amount (Ah) 0.82 0.51 0.68 0.72 0.74

[0088] The pre-lithiated electrode sheets of Example 1 and Comparative Examples 1-4, and the electrode sheet of Comparative Example 5 were assembled into a battery for cyclic performance testing. The test results are as Figure 1 shown. It can be seen from Figure 1 that the button battery made by the pre-lithiation method of the present invention has the highest discharge capacity when discharged against lithium. Compared with other pre-lithiation methods, the actual pre-lithiation amount is the highest under the same theoretical pre-lithiation amount, that is, it has the highest pre-lithiation efficiency.

[0089] The above are only the preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. A pre-lithiation method for a silicon-based anode sheet, characterized in that, It includes the following steps: S1. Wet both surfaces of the silicon-based anode sheet with a low-concentration electrolyte with a lithium salt mass concentration of 2-5%, attach a lithium strip to the wetted surface, then attach a flexible screen cloth to the surface of the lithium strip, and then perform cold roll pressing to obtain a composite structure anode sheet; the mesh number of the flexible screen cloth is 100-250 mesh, and the material is polyurethane, polyester or a combination thereof; the pressure of the cold roll pressing is 160-200 MPa; S2. Place the composite structure anode sheet in an inert atmosphere until the lithium strip has no metallic luster, then perform vacuum heating. After heating is completed, remove the flexible screen cloth to obtain a pre-lithiated silicon-based anode sheet.

2. The pre-lithiation method of the silicon-based anode sheet according to claim 1, characterized in that, The low-concentration electrolyte includes raw materials in the following mass percentages: 2-5% of lithium salt, 0-15% of fluoroethylene carbonate, and the balance is an organic solvent.

3. The pre-lithiation method of the silicon-based anode sheet according to claim 1, characterized in that, The dosage of the low-concentration electrolyte on a single surface of the electrode sheet is 30 to 50 mL / m 2 .

4. The pre-lithiation method of the silicon-based anode sheet according to claim 1, characterized in that The thickness of the lithium strip is 4-8 μm.

5. The pre-lithiation method of the silicon-based anode sheet according to claim 1, characterized in that In S2, the temperature of the vacuum heating is 60-75 °C, and the time is ≥24 h.

6. The pre-lithiation method of the silicon-based anode sheet according to claim 1, characterized in that The silicon-based anode sheet is obtained by coating a silicon-based anode slurry on the surface of a negative electrode current collector, followed by drying, winding, and die-cutting; the silicon-based anode slurry includes the following raw materials in parts by mass: 10-13 parts of a silicon-carbon anode material, 2-5 parts of a binder, 2-5 parts of a conductive agent, and 80-85 parts of deionized water.

7. A pre-lithiated silicon-based anode sheet, characterized in that, It is obtained by the method according to any one of claims 1-6.

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