Dual-purpose mixed conductor aqueous lithium ion battery adhesive and preparation method thereof

Abstract

The invention discloses a dual-purpose mixed conductor aqueous lithium ion battery adhesive and a preparation method thereof, and the preparation method comprises the following steps: (1) placing sodium alginate and urea in ethanol, stirring at room temperature, standing, and carrying out suction filtration to obtain a component 1; (2) dissolving dopamine hydrochloride in a Tris-HCl buffer solution, heating and stirring at 50-75 DEG C, and carrying out suction filtration to obtain a component 2; and (3) mixing the component 1 and the component 2. The adhesive can be used for being matched with a lithium ion positive electrode active material lithium iron phosphate and can also be used for being matched with a lithium ion battery negative electrode active material silicon. According to the adhesive disclosed by the invention, the conductive ion polymer and the conductive electron polymer are physically blended, so that the adhesive is endowed with conductivity, and the lithium ion battery electrode still has excellent electrochemical performance under the condition of reducing the dosage of the adhesive and the conductive agent. The electrode of the lithium ion battery can be loaded with more active materials, and the capacity of the lithium ion battery is improved. The adhesive provided by the invention is a water-based adhesive and is more environment-friendly.

Description

Technical Field

[0001] This invention relates to the field of lithium-ion batteries, and in particular to a dual-purpose hybrid conductor aqueous lithium-ion battery adhesive and its preparation method. Background Technology

[0002] Lithium-ion battery binders typically account for 1% to 10% of the total electrode mass in lithium-ion battery electrode manufacturing. Their main function is to bond the active material, conductive agent, and current collector together to form a complete electrode structure, thereby enhancing the electrode's mechanical strength and electrochemical performance. Commonly used lithium-ion battery binders include polyvinylidene fluoride (PVDF), cellulose (CMC), and styrene-butadiene rubber (SBR), most of which can only be used in a single electrode or are materials that are not conductive themselves. PVDF, the most widely used lithium-ion battery binder, requires the use of the organic solvent N-methylpyrrolidone (NMP), which is toxic and expensive.

[0003] Considering the aforementioned problems with common lithium-ion battery adhesives, conductive polymers are used as lithium-ion battery adhesives to impart conductivity to the batteries. Conductive polymers can be divided into ion-conducting polymers and electron-conducting polymers. Polymer chains such as polyethers and polyesters have a helical spatial structure. Cations coordinated with these polymer chains can migrate through vacancies within the helical channels under the influence of polymer chain segment movement; these polymers exhibit excellent ion-conducting capabilities. In polymers with multi-conjugated systems, the π-bond electrons in long chains are more active, especially the unbonded free electrons. Driven by external energy and the movement of macromolecular chain segments, they can conduct current; these polymers exhibit excellent electron-conducting capabilities. Furthermore, most lithium-ion battery adhesives can only be matched with one active material, while dual-purpose lithium-ion battery adhesives can be matched with different active materials, reducing material selection time during production.

[0004] Commonly used lithium-ion battery adhesives, such as polyvinylidene fluoride (PVDF), involve the use of materials that pollute the environment during production and use. Therefore, the use of water-based lithium-ion battery adhesives demonstrates their superiority: 1) Water-based lithium-ion battery adhesives are mostly water-soluble polymers, extracted primarily from natural substances, ensuring a green and pollution-free production process. 2) Water-based lithium-ion battery adhesives use water as a solvent, which is widely available, easily accessible, and pollution-free. 3) Water has a lower boiling point than N-methylpyrrolidone, a commonly used solvent in lithium-ion battery adhesives. This allows for faster drying during electrode production without producing toxic gases. Summary of the Invention

[0005] Conventional lithium-ion battery binders are neither environmentally friendly in their production nor application, lack conductivity, have limited functionality, and often can only be used with one type of active material. Therefore, a key challenge is how to enable conventional lithium-ion battery binders to simultaneously match different active materials and be applied to both the positive and negative electrodes of lithium-ion batteries. This would also address some of the pollution issues arising from the production and use of lithium-ion batteries, making the production process of lithium-ion battery electrodes more environmentally friendly. The purpose of this invention is to provide a method for preparing a dual-purpose hybrid conductor aqueous lithium-ion battery binder, solving the problems of existing lithium-ion battery binders being unable to be used simultaneously on both the positive and negative electrodes of lithium-ion batteries and lacking conductivity. Furthermore, it optimizes the preparation and application conditions, making it more environmentally friendly.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A dual-purpose hybrid conductor aqueous lithium-ion battery adhesive is prepared by the following method:

[0008] (1) Sodium alginate and urea were placed in ethanol, stirred at room temperature for 3 to 6 hours, allowed to stand for 1 to 3 hours, and then filtered to obtain component 1;

[0009] (2) Dissolve dopamine hydrochloride in Tris-HCl buffer, heat and stir at 50-75°C for 12-48 hours, and filter to obtain component 2;

[0010] (3) Mix component 1 and component 2 to obtain a dual-purpose hybrid conductor aqueous lithium-ion battery adhesive.

[0011] Preferably, in the above-mentioned dual-purpose hybrid conductor aqueous lithium-ion battery adhesive, the mass ratio of sodium alginate and urea in step (1) is 1:1 to 2; the ethanol is anhydrous ethanol, and the mass fraction of sodium alginate and urea in ethanol is 0.3 to 3%.

[0012] Preferably, in the above-mentioned dual-purpose hybrid conductor aqueous lithium-ion battery adhesive, the pH of the Tris-HCl buffer solution in step (2) is 8.5, and the concentration is any one of 10 mol / L, 0.02 mol / L, 0.1 mol / L, or 1 mol / L; the concentration of the dopamine hydrochloride in step (2) is 2 g / L.

[0013] Preferably, in the above-mentioned dual-purpose hybrid conductor aqueous lithium-ion battery adhesive, the mass ratio of component 1 and component 2 in step (3) is 1:0.8-3.

[0014] A method for preparing a lithium iron phosphate cathode for a hybrid conductor aqueous lithium-ion battery includes the following steps:

[0015] (1) Place lithium iron phosphate and conductive agent into a ball mill jar and ball mill for 20 to 120 minutes; add the ball-milled lithium iron phosphate, conductive agent and the binder obtained above into deionized water and stir for 12 to 48 hours to obtain positive electrode slurry;

[0016] (2) The obtained positive electrode slurry is coated onto a single-sided carbon-coated aluminum foil using a 100-500 μm scraper, and then transferred to a 60°C forced-air oven to dry for 0.5-2 hours. After surface curing, it is transferred to a 40-80°C vacuum oven to dry for 12-48 hours to obtain a mixed conductor aqueous lithium iron phosphate positive electrode for lithium-ion batteries.

[0017] Preferably, in the above-mentioned method for preparing the lithium iron phosphate cathode of a mixed conductor aqueous lithium-ion battery, the mass ratio of lithium iron phosphate, conductive agent, and binder in step (1) is 80:10:10, 91:3:6, or 93:4:3.

[0018] Preferably, in the above-mentioned method for preparing the lithium iron phosphate cathode of a hybrid conductor aqueous lithium-ion battery, the conductive agent in step (1) is either Ketjen Black or Super P; the solid content of the cathode slurry is 9-50% by mass; and the thickness of the single-sided carbon-coated aluminum foil in step (2) is 16 μm.

[0019] A method for preparing a silicon anode for a hybrid conductor aqueous lithium-ion battery includes the following steps:

[0020] (1) Add silicon powder, conductive agent and the binder obtained above to deionized water, and stir for 1 to 6 hours using a test tube disperser to obtain negative electrode slurry;

[0021] (2) The obtained negative electrode slurry is coated onto copper foil using a 100-300 μm scraper, and then transferred to a 60°C forced-air oven to dry for 0.5-2 hours. After surface curing, it is transferred to a 40-80°C vacuum oven to dry for 12-48 hours to obtain a silicon negative electrode for lithium-ion batteries.

[0022] Preferably, in the above-mentioned method for preparing the silicon anode of a hybrid conductor aqueous lithium-ion battery, the mass ratio of silicon powder, conductive agent and binder in step (1) is 60:20:20 or 70:20:10.

[0023] Preferably, in the above-mentioned method for preparing the silicon anode of a hybrid conductor aqueous lithium-ion battery, the size of the silicon powder in step (1) is any one of 50nm, 100nm or 1000nm; the conductive agent is either Ketjen Black or Super P; the solid content of the anode slurry is 15-70% by mass; and the thickness of the copper foil in step (2) is 15μm.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] (1) The adhesive of the present invention is a dual-purpose adhesive, which can be used to match both lithium iron phosphate, the positive electrode active material of lithium-ion batteries, and silicon, the negative electrode active material of lithium-ion batteries. Traditional adhesives can often only match one type of active material. If the matching is done in a conventional way, the capacity of the active material will decrease. The most common example is the use of polyvinylidene fluoride (PVDF) to match silicon. Silicon-based negative electrodes matched with PVDF often cannot effectively release the stress generated by the volume expansion effect during the charging and discharging process, which can easily lead to material performance degradation or even failure.

[0026] (2) The adhesive of the present invention uses a physical blend of conductive ion-conducting polymers and conductive electron-conducting polymers to impart conductivity to the adhesive, thereby achieving excellent electrochemical performance of the lithium-ion battery electrode while reducing the amount of adhesive and conductive agent used. This allows the lithium-ion battery electrode to load more active material under the same loading conditions, thus increasing the capacity of the lithium-ion battery. (3) The adhesive of the present invention is an aqueous adhesive. The most significant difference between aqueous adhesives and oil-based adhesives is the use of deionized water as a solvent, which is more environmentally friendly and greener. Moreover, the boiling point of deionized water is lower than that of N-methylpyrrolidone, the solvent used in existing adhesives such as polyvinylidene fluoride, allowing for the use of less energy to process the lithium-ion battery electrode during manufacturing. Attached Figure Description

[0027] Figure 1 The diagram shows the adhesion strength of the lithium iron phosphate cathode of the lithium-ion battery in Example 1 and Comparative Example 1.

[0028] Figure 2 The diagram shows the adhesion strength of the silicon anode of the lithium-ion battery in Example 3 and Comparative Example 3.

[0029] Figure 3 The graph shows the rate performance of lithium-ion battery lithium iron phosphate cathode cells in Example 1 and Comparative Example 1.

[0030] Figure 4 The figures show the 2C long-cycle diagrams of the lithium iron phosphate cathode batteries of Example 1 and Comparative Example 1.

[0031] Figure 5 The graph shows the rate performance of lithium-ion battery lithium iron phosphate cathode cells in Example 2 and Comparative Example 2.

[0032] Figure 6 The figures show the 2C long-cycle diagrams of the lithium iron phosphate cathode batteries of Example 2 and Comparative Example 2.

[0033] Figure 7 The graphs show the rate performance of the lithium-ion battery silicon anode cells in Example 3 and Comparative Example 3.

[0034] Figure 8 The figures show the 1C long-cycle diagrams of the lithium-ion silicon anode cells of Example 3 and Comparative Example 3.

[0035] Figure 9 The images are scanning electron microscope (SEM) images of the silicon anodes of lithium-ion batteries in Example 3 and Comparative Example 3 after 300 cycles. Detailed Implementation

[0036] Unless otherwise specified, the temperature parameters in this invention can be either constant temperature processing or processing within a certain temperature range. The constant temperature processing allows temperature fluctuations within the precision range controlled by the instrument.

[0037] Example 1: Lithium iron phosphate cathode for lithium-ion batteries using a dual-purpose hybrid conductor aqueous lithium-ion battery binder

[0038] Sodium alginate and urea were placed in ethanol and stirred at room temperature for 3 hours, then allowed to stand for 1 hour and filtered to obtain component 1. Dopamine hydrochloride was dissolved in Tris-HCl buffer solution with pH=8.5 and a concentration of 10 mmol / L, heated and stirred at 60°C for 24 hours, and filtered to obtain component 2. Component 1 and component 2 were mixed at a mass ratio of 1:1.5 to obtain a dual-purpose hybrid conductor aqueous lithium-ion battery adhesive.

[0039] 320 mg of lithium iron phosphate and 40 mg of Ketjen black were placed in a ball mill jar and milled for 40 minutes. After milling, 40 mg of binder was added to the 40 mg of binder, followed by 1.5 mL of deionized water. The mixture was stirred for 18 hours to obtain a slurry. The slurry was then coated onto a 15 μm thick single-sided carbon-coated aluminum foil using a 150 μm doctor blade. The coated foil was then dried in a 60°C forced-air oven for 1 hour. After surface curing, the foil was transferred to a 60°C vacuum oven for 14 hours to obtain the lithium-ion battery cathode. The obtained lithium-ion battery cathode was cut into small discs for battery assembly.

[0040] Example 2: Lithium iron phosphate cathode for lithium-ion batteries using a small amount of dual-purpose hybrid conductor aqueous lithium-ion battery binder

[0041] Sodium alginate and urea were placed in ethanol and stirred at room temperature for 4 hours, then allowed to stand for 2 hours and filtered to obtain component 1. Dopamine hydrochloride was dissolved in Tris-HCl buffer solution with pH=8.5 and a concentration of 0.02 mol / L, heated and stirred at 65°C for 30 hours, and filtered to obtain component 2. Component 1 and component 2 were mixed at a mass ratio of 1:2 to obtain a dual-purpose hybrid conductor aqueous lithium-ion battery adhesive.

[0042] 910 mg of lithium iron phosphate and 30 mg of Ketjen black were placed in a ball mill jar and milled for 45 minutes. After milling, 60 mg of binder was added to the 60 mg of binder, followed by 1 mL of deionized water. The mixture was stirred for 18 hours to obtain a slurry. The slurry was then coated onto a 15 μm thick single-sided carbon-coated aluminum foil using a 300 μm doctor blade. The coated foil was then dried in a 60°C forced-air oven for 1 hour. After surface curing, it was transferred to a 60°C vacuum oven for 14 hours to obtain the lithium-ion battery cathode. The obtained lithium-ion battery cathode was cut into small discs for battery assembly.

[0043] Example 3: Lithium-ion battery silicon anode using a dual-purpose hybrid conductor aqueous lithium-ion battery binder

[0044] Sodium alginate and urea were placed in ethanol and stirred at room temperature for 3 hours, then allowed to stand for 1 hour and filtered to obtain component 1. Dopamine hydrochloride was dissolved in Tris-HCl buffer solution with pH=8.5 and a concentration of 10 mmol / L, heated and stirred at 60°C for 24 hours, and filtered to obtain component 2. Component 1 and component 2 were mixed at a mass ratio of 1:1.5 to obtain a dual-purpose hybrid conductor aqueous lithium-ion battery adhesive.

[0045] 360 mg of 100 nm silicon powder, 120 mg of Super P, and 120 mg of binder were added to 4.5 mL of deionized water and stirred for 4 hours using a test tube disperser to obtain a negative electrode slurry. The obtained negative electrode slurry was coated onto a 15 μm thick copper foil using a 100 μm doctor blade, then transferred to a 60 °C forced-air oven for drying for 0.5 hours. After surface curing, it was transferred to an 80 °C vacuum oven for drying for 12 hours to obtain a lithium-ion battery silicon negative electrode. The obtained lithium-ion battery negative electrode was cut into small discs for battery assembly.

[0046] Comparative Example 1: Lithium iron phosphate cathode for lithium-ion batteries using polyvinylidene fluoride lithium-ion battery binder

[0047] 320 mg of lithium iron phosphate and 40 mg of Ketjen black were placed in a ball mill jar and milled for 40 minutes. After milling, 40 mg of polyvinylidene fluoride binder was added to the lithium iron phosphate and Ketjen black, followed by 1.5 mL of N-methylpyrrolidone. The mixture was stirred for 18 hours to obtain a slurry. The slurry was then coated onto a 15 μm thick single-sided carbon-coated aluminum foil using a 150 μm doctor blade. It was then transferred to a 60°C forced-air oven for drying for 2 hours. After surface curing, it was transferred to a 60°C vacuum oven for drying for 20 hours to obtain the lithium-ion battery cathode. The obtained lithium-ion battery cathode was cut into small discs for battery assembly.

[0048] Comparative Example 2: Lithium iron phosphate cathode for lithium-ion batteries using a small amount of polyvinylidene fluoride lithium-ion battery binder

[0049] 910 mg of lithium iron phosphate and 30 mg of Ketjen black were placed in a ball mill jar and milled for 45 minutes. After milling, 60 mg of polyvinylidene fluoride binder was added to the lithium iron phosphate and Ketjen black, followed by 1 mL of N-methylpyrrolidone. The mixture was stirred for 18 hours to obtain a slurry. The slurry was then coated onto a 15 μm thick single-sided carbon-coated aluminum foil using a 300 μm doctor blade. The coated foil was then dried in a 60°C forced-air oven for 2 hours. After surface curing, it was transferred to a 60°C vacuum oven for 20 hours to obtain the lithium-ion battery cathode. The obtained lithium-ion battery cathode was cut into small discs for battery assembly.

[0050] Comparative Example 3: Lithium-ion battery silicon anode using sodium alginate lithium-ion battery binder

[0051] 360 mg of 100 nm silicon powder, 120 mg of Super P, and 120 mg of sodium alginate binder were added to 4.5 mL of deionized water and stirred for 4 hours using a test tube disperser to obtain a negative electrode slurry. The obtained negative electrode slurry was coated onto a 15 μm thick copper foil using a 100 μm doctor blade, then transferred to a 60 °C forced-air oven for drying for 0.5 hours. After surface curing, it was transferred to an 80 °C vacuum oven for drying for 12 hours to obtain a lithium-ion battery silicon negative electrode. The obtained lithium-ion battery negative electrode was cut into small discs for battery assembly.

[0052] Performance testing

[0053] The peel strength of lithium iron phosphate cathodes and silicon anodes prepared using a dual-purpose hybrid conductor aqueous lithium-ion battery adhesive was tested and compared with the peel strength of a comparative example.

[0054] The rate performance and long-cycle performance of lithium iron phosphate cathode and silicon anode prepared by dual-use hybrid conductor aqueous lithium-ion battery binder were tested and compared with those of comparative examples.

[0055] The surface morphology of silicon anodes prepared with dual-use hybrid conductor aqueous lithium-ion battery binder was tested before and after 300 charge-discharge cycles, and compared with the surface morphology of electrodes in a comparative example.

[0056] The rate performance test results of the lithium iron phosphate cathode lithium-ion batteries of Example 1 and Comparative Example 1 are shown in Table 1.

[0057] Table 1

[0058]

[0059] The rate performance test results of the lithium iron phosphate cathode lithium-ion batteries of Example 2 and Comparative Example 2 are shown in Table 2.

[0060] Table 2

[0061]

[0062]

[0063] The rate performance test results of the silicon anode lithium-ion batteries of Example 3 and Comparative Example 3 are shown in Table 3.

[0064] Table 3

[0065]

[0066] Conclusion: Data from Tables 1, 2, and 3 show that the electrode using the dual-purpose hybrid conductor aqueous lithium-ion battery binder exhibits higher capacity and can store more energy. Furthermore, it maintains excellent electrochemical performance even with small amounts of conductive agent and binder. The dual-purpose hybrid conductor aqueous lithium-ion battery binder demonstrates excellent performance in both lithium iron phosphate cathodes and silicon anodes of lithium-ion batteries.

[0067] Figure 1 The diagram shows the adhesion strength of the lithium iron phosphate cathode in Example 1 and Comparative Example 1. Figure 1 It can be seen that the dual-purpose hybrid conductor aqueous lithium-ion battery adhesive has a stronger bonding strength to lithium iron phosphate than polyvinylidene fluoride has a stronger bonding strength to lithium iron phosphate.

[0068] Figure 2 The diagrams show the adhesion strength of the silicon anodes in lithium-ion batteries for Example 3 and Comparative Example 3. Figure 2 It can be seen that the dual-purpose hybrid conductor aqueous lithium-ion battery adhesive has a stronger bonding strength to silicon than sodium alginate has a stronger bonding strength to silicon.

[0069] Figure 3 The graphs show the rate performance of lithium-ion lithium iron phosphate cathode batteries in Example 1 and Comparative Example 1. Because the dual-use hybrid conductor aqueous lithium-ion battery binder is conductive, from... Figure 3 It can be seen that the batteries using electrodes with dual-purpose hybrid conductor aqueous lithium-ion battery binders have higher capacity at different rate limits.

[0070] Figure 4 The diagram shows the 2C long-cycle diagrams of the lithium iron phosphate cathode cells of Example 1 and Comparative Example 1.

[0071] Figure 5 The graphs show the rate performance of lithium-ion lithium iron phosphate cathode batteries in Example 2 and Comparative Example 2. Because the dual-use hybrid conductor aqueous lithium-ion battery binder is conductive, from... Figure 5 It can be seen that even with fewer conductive agents and binders, the electrode using the dual-purpose hybrid conductor aqueous lithium-ion battery binder still exhibits excellent electrochemical performance.

[0072] Figure 6 The diagram shows the 2C long-cycle diagrams of the lithium iron phosphate cathode cells of Example 2 and Comparative Example 2.

[0073] Figure 7 The graphs show the rate performance of lithium-ion silicon anode batteries in Example 3 and Comparative Example 3. Figure 7 The results show that even when using different active materials, the battery with electrodes using a dual-purpose hybrid conductor aqueous lithium-ion battery binder has a higher capacity.

[0074] Figure 8 The diagram shows the 1C long-cycle diagrams of the lithium-ion silicon anode cells of Example 3 and Comparative Example 3.

[0075] Figure 9 These are scanning electron microscope (SEM) images of the silicon anodes of lithium-ion batteries from Example 3 and Comparative Example 3 after 300 cycles. Figure 9 It can be seen that after 300 charge-discharge cycles, the electrode surface using the dual-purpose hybrid conductor aqueous lithium-ion battery adhesive is smoother, indicating that the dual-purpose hybrid conductor aqueous lithium-ion battery adhesive has the effect of suppressing the volume expansion of silicon anode.

Claims

1. A dual-purpose hybrid conductor aqueous lithium-ion battery adhesive, characterized in that... It is prepared by the following method: (1) Sodium alginate and urea were placed in ethanol, stirred at room temperature for 3 to 6 hours, allowed to stand for 1 to 3 hours, and then filtered to obtain component 1; (2) Dissolve dopamine hydrochloride in Tris-HCl buffer, heat and stir at 50-75°C for 12-48 hours, and filter to obtain component 2; (3) Mix component 1 and component 2 to obtain a dual-purpose hybrid conductor aqueous lithium-ion battery adhesive.

2. The dual-purpose hybrid conductor aqueous lithium-ion battery adhesive as described in claim 1, characterized in that, In step (1), the mass ratio of sodium alginate to urea is 1:1 to 2; the ethanol is anhydrous ethanol, and the mass fraction of sodium alginate and urea in ethanol is 0.3% to 3%.

3. The dual-purpose hybrid conductor aqueous lithium-ion battery adhesive as described in claim 1, characterized in that, The pH of the Tris-HCl buffer in step (2) is 8.5, and the concentration is any one of 10 mol / L, 0.02 mol / L, 0.1 mol / L, or 1 mol / L; the concentration of dopamine hydrochloride in step (2) is 2 g / L.

4. The dual-purpose hybrid conductor aqueous lithium-ion battery adhesive as described in claim 1, characterized in that, The mass ratio of component 1 and component 2 in step (3) is 1:0.8 to 3.

5. A method for preparing a lithium iron phosphate cathode for a hybrid conductor aqueous lithium-ion battery, characterized in that... Includes the following steps: (1) Place lithium iron phosphate and conductive agent into a ball mill jar and ball mill for 20 to 120 minutes; add the ball-milled lithium iron phosphate, conductive agent and binder obtained in claim 1 into deionized water and stir for 12 to 48 hours to obtain positive electrode slurry; (2) The obtained positive electrode slurry is coated onto a single-sided carbon-coated aluminum foil using a 100-500 μm scraper, and then transferred to a 60°C forced-air oven to dry for 0.5-2 hours. After surface curing, it is transferred to a 40-80°C vacuum oven to dry for 12-48 hours to obtain a mixed conductor aqueous lithium iron phosphate positive electrode for lithium-ion batteries.

6. The method for preparing the lithium iron phosphate cathode of a hybrid conductor aqueous lithium-ion battery as described in claim 5, characterized in that... In step (1), the mass ratio of lithium iron phosphate, conductive agent, and adhesive is 80:10:10, 91:3:6, or 93:4:

3.

7. The method for preparing the lithium iron phosphate cathode of a hybrid conductor aqueous lithium-ion battery as described in claim 5, characterized in that... The conductive agent in step (1) is either Ketjen Black or Super P; the solid content of the positive electrode slurry is 9-50% by mass; and the thickness of the single-sided carbon-coated aluminum foil in step (2) is 16 μm.

8. A method for preparing a silicon anode for a hybrid conductor aqueous lithium-ion battery, characterized in that... Includes the following steps: (1) Add silicon powder, conductive agent and binder obtained in claim 1 to deionized water, and stir for 1 to 6 hours using a test tube disperser to obtain negative electrode slurry; (2) The obtained negative electrode slurry is coated onto copper foil using a 100-300 μm scraper, and then transferred to a 60°C forced-air oven to dry for 0.5-2 hours. After surface curing, it is transferred to a 40-80°C vacuum oven to dry for 12-48 hours to obtain a silicon negative electrode for lithium-ion batteries.

9. The method for preparing the silicon anode of a hybrid conductor aqueous lithium-ion battery as described in claim 8, characterized in that... In step (1), the mass ratio of silicon powder, conductive agent, and adhesive is 60:20:20 or 70:20:

10.

10. The method for preparing the silicon anode of a hybrid conductor aqueous lithium-ion battery as described in claim 8, characterized in that... The silicon powder in step (1) has a size of 50nm, 100nm or 1000nm; the conductive agent is either Ketjen Black or Super P; the solid content of the negative electrode paste is 15-70% by mass; and the thickness of the copper foil in step (2) is 15μm.

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