Preparation method and application of a silicon-based anode material for efficiently constructing a stable SEI film

Abstract

A preparation method and application of a silicon-based anode material for efficiently constructing a stable SEI film, which relates to a preparation method and application of a silicon-based anode material. The purpose of the present invention is to solve the problems of poor conductivity, large volume effect of the current silicon anode material, and low specific capacity and Coulomb efficiency caused by the formation of an unstable solid electrolyte interface film. Method: First, prepare Si-RF nanospheres; second, prepare Si-RF-Mo-polydopamine superstructures; third, prepare high-density Si-C-MoSe2 spherical superstructures; A silicon-based anode material for efficiently constructing a stable SEI film is used as the anode material of a lithium-ion battery. The present invention obtains Si-C-MoSe2 superstructures through the methods of phenolic resin coating of silicon, nanosheet-sphere parallel adsorption growth technology, and high-temperature calcination selenization. The process flow is simple, the equipment requirements are low, and it has guiding significance for effectively constructing a stable SEI film on the surface of the silicon anode.

Description

Technical Field

[0001] The present invention relates to a preparation method and application of a silicon-based anode material. Background Art

[0002] At present, lithium-ion batteries have been applied in various fields. However, commercial graphite anodes can no longer meet the rapidly developing market demand due to their low capacity. Silicon materials are considered to be one of the most attractive anode materials for next-generation lithium-ion batteries because of their ultra-high theoretical specific capacity (4200 mAh / g), low lithium intercalation potential, and natural abundance. However, the key problem of silicon anodes is poor conductivity, which can cause volume expansion and cracking effects, especially inducing serious interfacial side reactions to expose fresh surfaces, resulting in continuous cracking / reconstruction of the solid electrolyte interface (SEI) on the electrode-electrolyte surface, thus sharply decreasing the electrode capacity and cycle stability, and having a low Coulombic efficiency, which limits the large-scale application of silicon materials. Among them, the interfacial chemistry between the electrode and the electrolyte plays a crucial role in determining the SEI characteristics. Therefore, finding a silicon-based anode material that can rapidly construct a stable SEI film is the key to achieving high specific capacity and Coulombic efficiency. Summary of the Invention

[0003] The purpose of the present invention is to solve the problems of poor conductivity, large volume effect, and formation of an unstable solid electrolyte interface film in current silicon anode materials, which lead to low specific capacity and Coulombic efficiency, and to provide a preparation method and application for efficiently constructing a stable SEI film silicon-based anode material.

[0004] A preparation method for efficiently constructing a stable SEI film silicon-based anode material is completed according to the following steps:

[0005] I. Preparation of Si-RF nanospheres:

[0006] ① First, disperse nano-silicon powder and poly(diallyldimethylammonium chloride) in deionized water, then stir and react, and then centrifuge to remove poly(diallyldimethylammonium chloride) to obtain positively charged modified silicon powder;

[0007] ② First, disperse the positively charged modified silicon powder in deionized water, then add ammonia water, resorcinol, and formaldehyde, and then stir and react to obtain a Si-RF mixed solution;

[0008] II. Preparation of Si-RF-Mo-polydopamine superstructure:

[0009] Adjust the pH value of the Si-RF mixed solution to 9 - 11, then add a mixed solution of ammonium molybdate tetrahydrate and deionized water under stirring conditions, stir for 5 min - 10 min, and then dropwise add a mixed solution of dopamine hydrochloride and deionized water under stirring conditions, and stir and react at room temperature to obtain a reaction product; wash and dry the reaction product to obtain a Si-RF-Mo-polydopamine superstructure;

[0010] III. Preparation of high-density Si-C-MoSe2 spherical superstructure:

[0011] ① Heat the Si-RF-Mo-polydopamine superstructure to 600 °C - 900 °C, and then calcine it under the protection of an Ar atmosphere at 600 °C - 900 °C to obtain a Si-C-MoO2 spherical superstructure;

[0012] ② Mix the Si-C-MoO2 spherical superstructure and Se powder evenly, and then calcine it under the protection of an Ar atmosphere at 400 °C - 800 °C to obtain a Si-C-MoSe2 spherical superstructure, which is a silicon-based anode material for efficiently constructing a stable SEI film.

[0013] A silicon-based anode material for efficiently constructing a stable SEI film is used as the anode material of a lithium-ion battery.

[0014] Principle of the present invention:

[0015] The high-density Si-C-MoSe2 spherical superstructure silicon-based anode material prepared by the present invention has a simple process flow and low equipment requirements. The C-MoSe2 nanosheets have good conductivity, can alleviate the volume expansion of Si nanospheres, and improve the utilization rate of silicon active substances. The outer shell MoSe2 can preferentially adsorb and reduce the widely used electrolyte additive fluoroethylene carbonate (FEC), thereby promoting the decomposition of FEC to form a SEI film with a large amount of poly(vinyl carbonate) and LiF, which has the characteristics of thinness, uniform distribution, stable mechanical structure, and high ionic conductivity, thereby improving the Coulomb efficiency and specific capacity of the Si-C-MoSe2 superstructure, and has guiding significance for effectively constructing a stable SEI film on the surface of the silicon anode.

[0016] Advantages of the present invention:

[0017] (1) The present invention obtains a Si-C-MoSe2 superstructure by means of phenolic resin coating of silicon, nanosheet-sphere parallel adsorption growth technology, and high-temperature calcination and selenization. The process flow is simple and the equipment requirements are low, which has guiding significance for effectively constructing a stable SEI film on the surface of the silicon anode;

[0018] (2) In the Si-C-MoSe2 superstructure prepared in the present invention, the Si-C nanospheres and the C-MoSe2 nanosheets are assembled into a high-density spherical superstructure. The C-MoSe2 nanosheets have good electrical conductivity, can alleviate the volume expansion of the Si nanospheres, have a high utilization rate of silicon active substances, and improve the volumetric specific capacity and cycling stability of the electrode material.

[0019] (3) In the Si-C-MoSe2 superstructure prepared in the present invention, compared with nano-Si and carbon shells, the outer shell MoSe2 can preferentially adsorb and reduce the widely used electrolyte additive fluoroethylene carbonate (FEC), thereby promoting the decomposition of FEC to form a SEI film with a large amount of poly(vinyl carbonate) and LiF, which has the characteristics of thinness, uniform distribution, stable mechanical structure, and high ionic conductivity, thus improving the Coulombic efficiency of the Si-C-MoSe2 superstructure. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 SEM image of the Si-C-MoSe2 spherical superstructure prepared in step 3 (2) of Example 1;

[0021] Figure 2 XRD pattern of the Si-C-MoSe2 spherical superstructure prepared in step 3 (2) of Example 1;

[0022] Figure 3 Charge-discharge curves of the Si-C-MoSe2 spherical superstructure and nano-silicon prepared in step 3 (2) of Example 1. In the figure, 1 is nano-silicon and 2 is the Si-C-MoSe2 spherical superstructure;

[0023] Figure 4 Rate performance graph of the Si-C-MoSe2 spherical superstructure and nano-silicon prepared in step 3 (2) of Example 1. In the figure, 1 is nano-silicon and 2 is the Si-C-MoSe2 spherical superstructure. DETAILED DESCRIPTION OF THE INVENTION

[0024] DETAILED DESCRIPTION OF THE INVENTION I: A preparation method of a silicon-based anode material for efficiently constructing a stable SEI film is specifically completed according to the following steps:

[0025] I. Preparation of Si-RF nanospheres:

[0026] ① First, disperse nano-silicon powder and poly(diallyldimethylammonium chloride) in deionized water, then stir and react, and then centrifuge to remove poly(diallyldimethylammonium chloride) to obtain silicon powder modified with positive charges;

[0027] ② First, disperse the silicon powder modified with positive charges in deionized water, then add ammonia water, resorcinol, and formaldehyde, and then stir and react to obtain a Si-RF mixed solution;

[0028] II. Preparation of Si-RF-Mo-polydopamine superstructure:

[0029] Adjust the pH value of the Si-RF mixed solution to 9 - 11, then add the mixed solution of ammonium molybdate tetrahydrate and deionized water under stirring conditions, stir for 5 min - 10 min, and then dropwise add the mixed solution of dopamine hydrochloride and deionized water under stirring conditions, and stir and react at room temperature to obtain a reaction product; wash and dry the reaction product to obtain the Si-RF-Mo-polydopamine superstructure;

[0030] III. Preparation of high-density Si-C-MoSe2 spherical superstructure:

[0031] ① Heat the Si-RF-Mo-polydopamine superstructure to 600 °C - 900 °C, and then calcine it under the protection of an Ar atmosphere at 600 °C - 900 °C to obtain a Si-C-MoO2 spherical superstructure;

[0032] ② Mix the Si-C-MoO2 spherical superstructure and Se powder evenly, and then calcine it under the protection of an Ar atmosphere at 400 °C - 800 °C to obtain a Si-C-MoSe2 spherical superstructure, which is the silicon-based anode material for efficiently constructing a stable SEI film.

[0033] The technological process of the Si-C-MoSe2 spherical superstructure prepared in this embodiment is simple and the equipment requirements are low. Its MoSe2 can preferentially adsorb and reduce the widely used electrolyte additive fluoroethylene carbonate (FEC), thereby promoting the decomposition of FEC to form an SEI film with a large amount of poly(vinylidene carbonate) and LiF. It has the characteristics of being thin, uniformly distributed, having a stable mechanical structure, and high ionic conductivity, can alleviate the volume expansion of Si nanospheres, has a high active material utilization rate, and improves the specific capacity and cycle stability of the electrode material.

[0034] Specific Embodiment 2: The difference between this embodiment and Specific Embodiment 1 is that the mass ratio of the nano-silicon powder to the volume of deionized water in step ① of step one is (10 mg - 80 mg):(10 mL - 50 mL); the volume ratio of the polydiallyldimethylammonium chloride to the volume of deionized water in step ① of step one is (1 mL - 5 mL):(10 mL - 50 mL); the stirring reaction time in step ① of step one is 1 h - 3 h. Other steps are the same as those in Specific Embodiment 1.

[0035] Embodiment 3: The difference between this embodiment and Embodiment 1 or 2 is as follows: In step 1②, the mass ratio of the positively charged silicon powder to the volume of deionized water is (10 mg - 80 mg):(50 mL - 150 mL); in step 1②, the volume ratio of ammonia water to deionized water is (0.5 mL - 3 mL):(50 mL - 150 mL). Other steps are the same as those in Embodiment 1 or 2.

[0036] Embodiment 4: The difference between this embodiment and any one of Embodiments 1 to 3 is as follows: In step 1②, the mass ratio of resorcinol to the volume of deionized water is (100 mg - 200 mg):(50 mL - 150 mL); in step 1②, the volume ratio of formaldehyde to deionized water is (100 μL - 200 μL):(50 mL - 150 mL); in step 1②, the stirring reaction time is 1 h - 6 h. Other steps are the same as those in Embodiments 1 to 3.

[0037] Embodiment 5: The difference between this embodiment and any one of Embodiments 1 to 4 is as follows: In step 2, the volume ratio of the Si-RF mixed solution to the mixed solution of ammonium molybdate tetrahydrate and deionized water is 20 mL:(15 mL - 30 mL); in the mixed solution of ammonium molybdate tetrahydrate and water in step 2, the mass ratio of ammonium molybdate tetrahydrate to the volume of deionized water is (0.05 g - 0.3 g):(15 mL - 30 mL). Other steps are the same as those in Embodiments 1 to 4.

[0038] Embodiment 6: The difference between this embodiment and any one of Embodiments 1 to 5 is as follows: In step 2, the volume ratio of the Si-RF mixed solution to the mixed solution of dopamine hydrochloride and deionized water is 20 mL:(2 mL - 7 mL); in the mixed solution of dopamine hydrochloride and deionized water in step 2, the mass ratio of dopamine hydrochloride to the volume of deionized water is (0.05 g - 0.3 g):(2 mL - 7 mL). Other steps are the same as those in Embodiments 1 to 5.

[0039] Embodiment 7: The difference between this embodiment and any one of Embodiments 1 to 6 is as follows: In step 2, the stirring reaction time is 6 h - 9 h; in step 2, the reaction product is first washed 3 to 5 times with deionized water, then washed 3 to 5 times with absolute ethanol, and then dried to obtain the Si-RF-Mo-polydopamine superstructure. Other steps are the same as those in Embodiments 1 to 6.

[0040] Embodiment 8: The difference between this embodiment and any one of Embodiments 1 to 7 is as follows: the calcination time described in Step 3① is 3h to 7h; the heating rate described in Step 3① is 1°C / min to 5°C / min; the mass ratio of the Si-C-MoO2 spherical superstructure to Se powder described in Step 3② is 1:(1 to 10); the calcination time described in Step 3② is 6h to 12h. Other steps are the same as those in Embodiments 1 to 7.

[0041] Embodiment 9: This embodiment is an efficient method for constructing a stable SEI film silicon-based anode material for use as the anode material of a lithium-ion battery.

[0042] Embodiment 10: The difference between this embodiment and Embodiment 9 is as follows: the preparation method of the lithium-ion battery is as follows: mix an efficient method for constructing a stable SEI film silicon-based anode material, acetylene black, and sodium carboxymethylcellulose in a mass ratio of 8:1:1, then drop in absolute ethanol to obtain a slurry; uniformly coat the slurry on a copper foil, and then place it in a vacuum drying oven at 60°C for 12h to obtain a working electrode; use a lithium metal sheet as the counter electrode; dissolve LiPF6 in a mixed solution of EC and DEC to obtain an electrolyte, and select celgard 2400 type as the separator to obtain a lithium-ion battery; the volume ratio of EC to DEC in the electrolyte is 3:7, and the concentration of LiPF6 is 1mol / L. Other steps are the same as those in Embodiment 9.

[0043] The following examples are used to verify the beneficial effects of the present invention:

[0044] Example 1. A preparation method of an efficient method for constructing a stable SEI film silicon-based anode material, characterized in that the preparation method is specifically completed according to the following steps:

[0045] I. Preparation of Si-RF nanospheres:

[0046] ①. First, disperse nanosilicon powder and poly(diallyldimethylammonium chloride) in deionized water, then stir and react for 2h, and then centrifuge to remove poly(diallyldimethylammonium chloride) to obtain positively charged modified silicon powder;

[0047] In Step ① of Step I, the mass ratio of the nanosilicon powder to the volume of deionized water is 50mg:20mL;

[0048] In Step ① of Step I, the volume ratio of poly(diallyldimethylammonium chloride) to deionized water is 2mL:20mL;

[0049] ②. First, disperse the positively charged modified silicon powder in deionized water, then add ammonia water, resorcinol, and formaldehyde, and then stir and react for 3h to obtain a Si-RF mixed solution;

[0050] In step ② of step one, the mass - to - volume ratio of the positively - charged modified silicon powder to deionized water is 50 mg:100 mL;

[0051] In step ② of step one, the volume ratio of ammonia water to deionized water is 1 mL:100 mL;

[0052] In step ② of step one, the mass - to - volume ratio of resorcinol to deionized water is 150 mg:100 mL;

[0053] In step ② of step one, the volume ratio of formaldehyde to deionized water is 150 μL:100 mL;

[0054] II. Preparation of Si - RF - Mo - polydopamine superstructure:

[0055] Adjust the pH value of the Si - RF mixed solution to 10, then add the mixed solution of ammonium molybdate tetrahydrate and deionized water under stirring conditions, stir for 5 min, and then dropwise add the mixed solution of hydrochloric acid dopamine and deionized water under stirring conditions. Stir and react at room temperature for 6 h to obtain a reaction product; wash and dry the reaction product to obtain the Si - RF - Mo - polydopamine superstructure;

[0056] In step two, the volume ratio of the Si - RF mixed solution to the mixed solution of ammonium molybdate tetrahydrate and deionized water is 20 mL:20 mL;

[0057] In the mixed solution of ammonium molybdate tetrahydrate and water in step two, the mass - to - volume ratio of ammonium molybdate tetrahydrate to deionized water is 0.1 g:20 mL;

[0058] In step two, the volume ratio of the Si - RF mixed solution to the mixed solution of hydrochloric acid dopamine and deionized water is 20 mL:5 mL;

[0059] In the mixed solution of hydrochloric acid dopamine and deionized water in step two, the mass - to - volume ratio of hydrochloric acid dopamine to deionized water is 0.1 g:5 mL;

[0060] In step two, first wash the reaction product 5 times with deionized water, then wash the reaction product 5 times with absolute ethanol, and then dry to obtain the Si - RF - Mo - polydopamine superstructure;

[0061] III. Preparation of high - density Si - C - MoSe₂ spherical superstructure:

[0062] ①. Heat the Si - RF - Mo - polydopamine superstructure to 700 °C, and then calcine it at 700 °C under the protection of an Ar atmosphere for 3 h to obtain a Si - C - MoO₂ spherical superstructure;

[0063] In step 3, the heating rate described in ① is 2 °C / min;

[0064] ② Mix the Si-C-MoO2 spherical superstructure and Se powder evenly, and then calcine at 600 °C under Ar atmosphere protection for 9 h to obtain the Si-C-MoSe2 spherical superstructure (a high-efficiency silicon-based anode material for constructing a stable SEI film);

[0065] In step 3②, the mass ratio of the Si-C-MoO2 spherical superstructure to Se powder is 1:9.

[0066] Figure 1 It is the SEM image of the Si-C-MoSe2 spherical superstructure prepared in step 3② of Example 1;

[0067] From Figure 1 It can be seen that the Si@C nanospheres are uniformly embedded in the C-MoSe2 nanosheet superstructure to form a high-density Si-C-MoSe2 spherical superstructure.

[0068] Figure 2 It is the XRD pattern of the Si-C-MoSe2 spherical superstructure prepared in step 3② of Example 1;

[0069] Diffraction peaks of Si and MoSe2 can be observed from the XRD pattern, which can confirm that the Si-C-MoSe2 superstructure is successfully prepared.

[0070] Application test 1: Mix the Si-C-MoSe2 spherical superstructure, acetylene black, and sodium carboxymethylcellulose in a mass ratio of 8:1:1, and then drop in anhydrous ethanol to obtain a slurry; uniformly coat the slurry on a copper foil, and then place it in a vacuum drying oven at 60 °C for 12 h to obtain a working electrode; use a lithium metal sheet as the counter electrode; dissolve LiPF6 in a mixed solution of EC and DEC to obtain an electrolyte, and select celgard 2400 type as the separator to obtain a lithium-ion battery; the volume ratio of EC to DEC in the electrolyte is 3:7, and the concentration of LiPF6 is 1 mol / L. Constant current charge and discharge tests are used to measure the Coulomb efficiency, specific capacity, cycle life, rate performance, and energy density, etc.

[0071] Application test 2: The difference between this test and Application test 1 is that nanosilicon, acetylene black, and sodium carboxymethylcellulose are mixed in a mass ratio of 8:1:1. Other steps and parameters are the same as those in Application test 1.

[0072] Figure 3 It is the charge and discharge curve of the Si-C-MoSe2 spherical superstructure and nanosilicon prepared in step 3② of Example 1. In the figure, 1 is nanosilicon, and 2 is the Si-C-MoSe2 spherical superstructure;

[0073] From Figure 3It can be seen that the initial Coulombic efficiency of the Si-C-MoSe2 superstructure is as high as 86%, while that of the silicon powder is only 64%. This indicates that the C-MoSe2 motif in the superstructure can significantly improve the Coulombic efficiency of the Si-C-MoSe2 superstructure, which is of guiding significance for effectively constructing a stable SEI film on the surface of the silicon anode.

[0074] Figure 4 It is the rate performance graph of the Si-C-MoSe2 spherical superstructure and nano-silicon prepared in step ③ of Example 1. In the figure, 1 is nano-silicon and 2 is the Si-C-MoSe2 spherical superstructure.

[0075] From Figure 4 It can be seen that the charge specific capacity of the Si-C-MoSe2 superstructure at each current density is much higher than that of the nano-silicon electrode. This result shows that the C-MoSe2 motif in the Si-C-MoSe2 superstructure can alleviate the volume expansion of the Si nanospheres, with a high utilization rate of silicon active materials, enabling the Si-C-MoSe2 superstructure to exhibit higher rate performance.

Claims

1. A preparation method of a silicon-based anode material for efficiently constructing a stable SEI film, characterized in that The preparation method is specifically completed according to the following steps: I. Preparation of Si-RF nanospheres: ①. First, disperse nano-silicon powder and poly(diallyldimethylammonium chloride) in deionized water, then stir and react, and then centrifuge to remove poly(diallyldimethylammonium chloride) to obtain positively charged modified silicon powder; ②. First, disperse the positively charged modified silicon powder in deionized water, then add ammonia water, resorcinol, and formaldehyde, and then stir and react to obtain a Si-RF mixed solution; II. Preparation of Si-RF-Mo-polydopamine superstructure: Adjust the pH value of the Si-RF mixed solution to 9-11, then add a mixed solution of ammonium molybdate tetrahydrate and deionized water under stirring conditions, stir for 5 min - 10 min, and then dropwise add a mixed solution of dopamine hydrochloride and deionized water under stirring conditions, and stir and react at room temperature to obtain a reaction product; wash and dry the reaction product to obtain a Si-RF-Mo-polydopamine superstructure; III. Preparation of high-density Si-C-MoSe2 spherical superstructure: ①. Heat the Si-RF-Mo-polydopamine superstructure to 600 °C - 900 °C, and then calcine it under the protection of an Ar atmosphere at 600 °C - 900 °C to obtain a Si-C-MoO2 spherical superstructure; ②. Mix the Si-C-MoO2 spherical superstructure and Se powder evenly, and then calcine it under the protection of an Ar atmosphere at 400 °C - 800 °C to obtain a Si-C-MoSe2 spherical superstructure, which is the silicon-based anode material for efficiently constructing a stable SEI film.

2. The preparation method of a silicon-based anode material for efficiently constructing a stable SEI film according to claim 1, characterized in that In step I①, the mass ratio of the nano-silicon powder to the volume of deionized water is (10 mg - 80 mg):(10 mL - 50 mL); in step I①, the volume ratio of poly(diallyldimethylammonium chloride) to deionized water is (1 mL - 5 mL):(10 mL - 50 mL); in step I①, the stirring reaction time is 1 h - 3 h.

3. The preparation method of a silicon-based anode material for efficiently constructing a stable SEI film according to claim 1, characterized in that In step I②, the mass ratio of the positively charged modified silicon powder to the volume of deionized water is (10 mg - 80 mg):(50 mL - 150 mL); in step I②, the volume ratio of ammonia water to deionized water is (0.5 mL - 3 mL):(50 mL - 150 mL).

4. The preparation method of a silicon-based anode material for efficiently constructing a stable SEI film according to claim 1, wherein In step I②, the mass ratio of resorcinol to the volume of deionized water is (100 mg - 200 mg):(50 mL - 150 mL); in step I②, the volume ratio of formaldehyde to deionized water is (100 μL - 200 μL):(50 mL - 150 mL); in step I②, the stirring reaction time is 1 h - 6 h.

5. The preparation method of a silicon-based anode material for efficiently constructing a stable SEI film according to claim 1, characterized in that In step II, the volume ratio of the Si-RF mixed solution to the mixed solution of ammonium molybdate tetrahydrate and deionized water is 20 mL:(15 mL - 30 mL); in the mixed solution of ammonium molybdate tetrahydrate and water in step II, the mass ratio of ammonium molybdate tetrahydrate to the volume of deionized water is (0.05 g - 0.3 g):(15 mL - 30 mL).

6. The preparation method of a silicon-based anode material for efficiently constructing a stable SEI film according to claim 1, characterized in that The volume ratio of the Si-RF mixed solution to the mixed solution of dopamine hydrochloride and deionized water described in Step 2 is 20 mL:(2 mL - 7 mL); the mass ratio of dopamine hydrochloride to the volume of deionized water in the mixed solution of dopamine hydrochloride and deionized water described in Step 2 is (0.05 g - 0.3 g):(2 mL - 7 mL).

7. The preparation method of a silicon-based anode material for efficiently constructing a stable SEI film according to claim 1, wherein The stirring reaction time described in Step 2 is 6 h - 9 h; in Step 2, the reaction product is first washed 3 to 5 times with deionized water, then washed 3 to 5 times with absolute ethanol, and then dried to obtain the Si-RF-Mo-polydopamine superstructure.

8. The preparation method of a silicon-based anode material for efficiently constructing a stable SEI film according to claim 1, characterized in that The calcination time described in Step 3① is 3 h - 7 h; the heating rate described in Step 3① is 1 °C / min - 5 °C / min; the mass ratio of the Si-C-MoO2 spherical superstructure to the Se powder described in Step 3② is 1:(1 - 10); the calcination time described in Step 3② is 6 h - 12 h.

9. Application of a silicon-based anode material for efficiently constructing a stable SEI film prepared by the preparation method according to claim 1, characterized in that A silicon-based anode material for efficiently constructing a stable SEI film is used as the anode material of a lithium-ion battery.

10. The application of a silicon-based anode material for efficiently constructing a stable SEI film according to claim 9, characterized in that The preparation method of the lithium-ion battery is as follows: A silicon-based anode material for efficiently constructing a stable SEI film, acetylene black, and sodium carboxymethylcellulose are mixed in a mass ratio of 8:1:1, and then absolute ethanol is added dropwise to obtain a slurry; the slurry is uniformly coated on a copper foil and then placed in a vacuum drying oven at 60 °C for 12 h to obtain a working electrode; a lithium metal sheet is used as the counter electrode; LiPF6 is dissolved in a mixed solution of EC and DEC to obtain an electrolyte, and a celgard 2400 type separator is selected to obtain a lithium-ion battery; the volume ratio of EC to DEC in the electrolyte is 3:7, and the concentration of LiPF6 is 1 mol / L.

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