High-stability alkaline battery positive electrode composite anti-corrosion conductive material and preparation thereof

Abstract

The invention relates to the field of batteries, in particular to a high-stability alkaline battery positive electrode composite anti-corrosion conductive material and a preparation method thereof. The conductive material comprises 40-50 parts of graphene, 20-30 parts of carbon nanotubes, 8-15 parts of a binder, 20-30 parts of an anti-corrosion composite material and 8-12 parts of a reinforcing agent, the preparation method comprises the following steps: adding the binder into the solvent for dissolving, then adding the graphene, the carbon nanotubes, the anti-corrosion composite material and the reinforcing agent, and uniformly mixing to obtain the anti-corrosion composite material. According to the conductive material, the comprehensive performance of the material in the aspects of corrosion resistance, conductivity, stability and the like is improved, the requirements of a high-stability alkaline battery positive electrode material can be met, the overall performance of a battery is improved, and the service life of the battery is prolonged. The invention also provides a preparation method of the conductive material, and the method is simple to operate, easy to control and convenient for industrial production.

Description

Technical Field

[0001] The present invention relates to the field of batteries, and in particular to a high-stability alkaline battery positive electrode composite anti-corrosion conductive material and a preparation method thereof. Background Art

[0002] Currently, the secondary batteries with large-scale commercial applications include lead-acid batteries, nickel-metal hydride batteries, and lithium-ion batteries. However, they all have certain limitations. For example, the low energy density and environmentally harmful properties of lead-acid batteries have put them on the verge of obsolescence; the low operating voltage and power density, as well as the limited service life, have restricted the promotion and application of nickel-metal hydride batteries; and lithium batteries are limited by flammable and highly viscous organic electrolytes, high manufacturing costs, and limited lithium and cobalt resources. These factors pose significant safety risks in large-scale applications, and their fast charging and discharging capabilities are poor, resulting in high costs. Among the many known battery systems, alkaline nickel-zinc batteries, as green and environmentally friendly aqueous batteries, are the most likely to meet these requirements. With advantages such as high power, abundant electrode material resources, and excellent safety performance, they are considered a strong competitor and alternative to lithium, lead-acid, and nickel-metal hydride batteries.

[0003] Despite the numerous advantages of alkaline nickel-zinc batteries, and their over 200-year history, their widespread adoption has been slow. Currently, commercially available batteries are very limited, and their performance is relatively poor. This phenomenon is primarily due to corrosion of the electrode materials, which contributes to the poor cycling stability of nickel-zinc batteries. To alleviate these issues, the present invention aims to develop a conductive material with excellent stability and resistance to alkaline corrosion. Summary of the Invention

[0004] To address the above-mentioned issues, the present invention provides a highly stable alkaline battery positive electrode composite anti-corrosion conductive material. This conductive material combines the advantages of multiple materials, including graphene, carbon nanotubes, polyaniline, core-shell particles, and a reinforcing agent. Through a rational formulation and preparation process, it achieves comprehensive improvements in corrosion resistance, conductivity, and stability. This material meets the requirements of a highly stable alkaline battery positive electrode material and improves the overall performance and service life of the battery. The present invention also provides a method for preparing this conductive material, which is simple to operate, easy to control, and amenable to industrial production.

[0005] The technical solutions adopted by the present invention to achieve the above-mentioned purpose are: A high-stability alkaline battery positive electrode composite anti-corrosion conductive material, comprising the following components by weight: 40-50 parts of graphene, 20-30 parts of carbon nanotubes, 8-15 parts of a binder, 20-30 parts of an anti-corrosion composite material, and 8-12 parts of a reinforcing agent; The method for preparing the anti-corrosion composite material comprises the following steps: Step 1: dissolving tin tetrachloride in deionized water to prepare a 0.2-0.5 mol / L solution, adding polyvinyl pyrrolidone, adjusting the pH to 8-10, reacting for 2-4 hours, and purifying to obtain nano-SnO2 core layer particles; Step 2: Using the nano-SnO2 core layer particles prepared in step 1 as a matrix, zirconium tetrachloride and deionized water as precursors, at a temperature of 200-300°C and a pressure of 2-5 Torr, alternately introducing ZrCl4 and H2O vapor for deposition to obtain SnO2-ZrO2 core-shell particles; Step 3: Disperse the SnO2-ZrO2 core-shell particles in HCl solution, ultrasonically treat, add aniline monomer and ammonium persulfate, and react for 4-5 hours at a water bath temperature of 25-40°C to obtain cross-linked polyaniline-coated SnO2-ZrO2.

[0006] Preferably, in step 1, the weight ratio of SnCl4 to polyvinyl pyrrolidone is 1:0.5-2, and the concentration of ammonia water is 25-28%.

[0007] Preferably, in step 2, the gas flow rates of ZrCl4 steam and H2O steam are 0.01-0.05 g / min and 0.1-0.3 g / min, respectively.

[0008] Preferably, in step 3, the weight ratio of SnO2-ZrO2 core-shell particles, aniline monomer, and ammonium persulfate is 100:100-160:20-25.

[0009] This corrosion-resistant composite material features a multi-level core-shell structure. The SnO2 core layer exhibits semiconductor properties, providing a certain degree of conductivity and acting as a bridge for electron transfer. Furthermore, a passivation layer forms on its surface, mitigating corrosion in alkaline electrolytes such as KOH. The ZrO2 shell layer exhibits excellent alkaline corrosion resistance. A dense coating formed through an ALD process blocks electrolyte penetration and prevents oxidative dissolution of the SnO2 core. The synergistic effect of the SnO2 core's conductivity and the passivation protection of the ZrO2 shell reduces the corrosion current density in alkaline environments. A polyaniline (PANI) coating is further added to form a charge transfer complex with the SnO2-ZrO2 surface, enhancing interfacial conductivity. Furthermore, the PANI adsorbs OH⁻ ions to form a protective film, inhibiting oxygen diffusion and corrosion of metal active sites. The PAI coating uniformly coats the core-shell particles through in-situ polymerization, preventing stress concentration-induced cracking in the coating. This anti-corrosion composite material works synergistically with the conductive network of graphene / carbon nanotubes. The multilayered core-shell particles are embedded in the conductive network, and the polyaniline coating connects to the carbon material through π-π stacking or hydrogen bonding, reducing interfacial contact resistance. The graphene / carbon nanotubes are responsible for rapid electron transport, while the PANI coating promotes ion migration, achieving a bicontinuous conductive path and reducing electrode polarization. PVDF secures the anti-corrosion composite material to the graphene and carbon nanotubes through molecular chain entanglement and van der Waals forces, enhancing interfacial bonding strength.

[0010] Preferably, the preparation method of the enhancer is as follows: Step a, mixing the glass flakes with the etching solution, etching for 10-20 minutes at 20-30°C and a stirring speed of 300-500 rpm, and then washing and drying; Step b, mixing the glass flakes after the etching treatment in step a with an activation solution, activating them at 55-65° C. for 35-45 minutes, and then washing and drying them; Step c, placing the glass flakes activated in step b in a hydrolyzate, ultrasonically dispersing for 10 minutes, cyclically immersing at a pressure of -0.09 MPa for 2-3 times, each time for 10 minutes, then reacting at 45-55° C. for 8-10 hours, and purifying to obtain modified glass flakes; Step d: mixing the modified glass flakes obtained in step c with nano-SiO2, a dispersant, and ethanol, ball-milling, and drying to obtain a reinforcing agent.

[0011] Preferably, in step a, the etching solution comprises the following components by volume percentage: 5-10% hydrofluoric acid, 1-3% sulfuric acid, and 8-12% ethylene glycol. The concentration of hydrofluoric acid is 40%, and the concentration of sulfuric acid is 98%. The etching solution also includes hexadecyltrimethylammonium bromide with a mass concentration of 1-2 g / L, and the balance is water. The weight-to-volume ratio of glass flakes to etching solution is 1:8-12 g / mL.

[0012] Preferably, the activation solution in step b comprises the following components by weight percentage: 2-4% H2O2 with a concentration of 30%, 0.5-1.5% nitric acid with a concentration of 65%, and the balance being water. The weight-to-volume ratio of glass flakes to activation solution is 1:8-12 g / mL.

[0013] Preferably, the hydrolyzate in step c comprises, by weight percentage, 5-7% KH570, 15-20% buffer, 0.05% ammonium fluoride, and the balance anhydrous ethanol.

[0014] Preferably, in step d, the weight ratio of modified glass flakes, nano-SiO2, and dispersant is 70-80:20-30:0.1-0.3, and the weight-to-volume ratio of modified glass flakes to ethanol is 7-8g / 3-5ml.

[0015] In the reinforcing agent, the glass flakes are first modified. Hydrofluoric acid selectively etches the amorphous regions of the glass flakes, forming a porous surface that increases the specific surface area, enhances mechanical anchoring with the PVDF binder, and improves peel strength. Sulfuric acid oxidation removes surface impurities, and cetyltrimethylammonium bromide adsorption inhibits excessive corrosion, ensuring structural integrity. During the activation process, H₂O₂ and HNO₃ synergistically oxidize to generate abundant surface hydroxyl groups (-OH), providing active sites for silane coupling. Further interface optimization of the silane coupling agent involves condensation of KH570 with the hydroxyl groups on the glass flakes, forming a hydrophobic-oleophilic interface and further enhancing compatibility with the adhesive. Ammonium fluoride catalyzes the condensation reaction, reducing the activation energy and accelerating interfacial bonding. Pressure cycling forces the hydrolyzed solution to penetrate the pores of the glass flakes, ensuring uniform coating. SiO₂ particles fill the micro-gaps between the glass flakes, improving fracture toughness through crack deflection and bridging mechanisms. The synergistic effect of this reinforcing agent and the conductive materials (graphene / carbon nanotubes) allows the high modulus of the modified glass flakes to provide support for the brittle carbon materials (graphene / carbon nanotubes), inhibiting volume expansion during charge and discharge that could lead to fracture of the conductive network. Nano-SiO2 fills the pores of the carbon material, reducing side reactions caused by electrolyte penetration (such as graphene oxidation), thereby extending cycle life. The high rigidity of the glass flakes disperses local stress, preventing the SnO2-ZrO2 core-shell particles from breaking during cycling.

[0016] The preparation method of the above-mentioned high-stability alkaline battery positive electrode composite anti-corrosion conductive material is as follows: PVDF is added to the solvent N-methylpyrrolidone, with the weight ratio of PVDF to NMP being 1:8-10, stirred to dissolve, and then graphene, carbon nanotubes, anti-corrosion composite materials, and reinforcing agents are added and mixed evenly to obtain the product.

[0017] The present invention has the following beneficial effects: The high-stability alkaline battery positive electrode composite anti-corrosion conductive material provided by the present invention combines the advantages of multiple materials such as graphene, carbon nanotubes, polyaniline, core-shell structure particles and reinforcing agents. Through reasonable proportions and preparation processes, the material's comprehensive performance in terms of corrosion resistance, conductivity, stability, etc. is improved, which can meet the requirements of high-stability alkaline battery positive electrode materials and improve the overall performance and service life of the battery.

[0018] In this conductive material, the synergistic effect of graphene and carbon nanotubes (CNTs) is remarkable: graphene possesses excellent electrical conductivity and a large specific surface area, while CNTs possess good electrical conductivity and mechanical strength. The interwoven graphene and CNTs form a three-dimensional conductive network, effectively enhancing the material's electrical conductivity, reducing the battery's internal resistance, and improving the battery's charge and discharge efficiency. The anti-corrosion composite material is chemically deposited onto the surface of nano-SnO2 core particles to form a ZrO2 shell, forming a SnO2-ZrO2 core-shell structure. This core-shell structure effectively isolates external corrosive substances from direct contact with the SnO2 core, providing a strong physical shield and preventing SnO2 corrosion. The SnO2-ZrO2 core-shell particles are then reacted with aniline monomer, ammonium persulfate, and other agents to form a cross-linked polyaniline coating on the core-shell particle surface. Polyaniline itself has excellent chemical stability and electrochemical activity, and the polyaniline coating not only provides corrosion protection but also exhibits excellent electrochemical activity. During the battery's charge and discharge processes, polyaniline participates in electrochemical reactions, further improving the battery's electrical conductivity and electrochemical performance. The SnO2-ZrO2 core-shell structure ensures the material maintains structural stability during the charge and discharge process. The ZrO2 shell effectively buffers the volume changes of the SnO2 during charge and discharge, preventing material pulverization and shedding, thereby improving the material's cycling stability. The addition of a reinforcing agent further enhances the material's mechanical strength and stability, providing support and protection during the battery's charge and discharge processes, preventing deformation and damage.

[0019] The preparation method of the present invention is simple to operate, easy to control and convenient for industrial production. DETAILED DESCRIPTION

[0020] The following will be combined with the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the embodiments described are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments of the present application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0021] Graphene, fixed carbon content 99.5-999.9%, Qingdao Tianfeng Graphite Co., Ltd.; carbon nanotubes, active ingredient content 99.9%, Ningbo Luofei Nanotechnology Co., Ltd.; aniline, purity AR, ≥99.5%, brand, Yuanye; cetyltrimethylammonium bromide, content 99%, Henan Lanxing Chemical Products Co., Ltd.; nano-SiO2, 20 nm, Hangzhou Jiuli Biomaterials Co., Ltd.; sodium polyacrylate, content 99%, Henan Duohui Chemical Products Co., Ltd.; glass flakes, 325 mesh ultrafine powder, Lingshou County Fanhong Mining Co., Ltd.; acetic acid-sodium acetate buffer (pH 4.5), Shanghai Yuanye Biotechnology Co., Ltd. All raw materials used in the following examples were commercially available products.

[0022] Example 1 A high-stability alkaline battery positive electrode composite anti-corrosion conductive material, comprising the following components by weight: 45 parts of graphene, 25 parts of carbon nanotubes, 10 parts of PVDF binder, 25 parts of anti-corrosion composite material, and 10 parts of reinforcing agent; The method for preparing the anti-corrosion composite material comprises the following steps: Step 1: dissolving tin tetrachloride (SnCl4·5H2O) in deionized water to prepare a 0.3 mol / L solution; adding polyvinyl pyrrolidone, and adjusting the pH to 8-10 with ammonia water; stirring at 400 rpm at 80°C for 3 hours; washing by centrifugation, washing with deionized water three times and ethanol once, centrifuging at 8000 rpm for 10 minutes each; and finally vacuum drying at 60°C for 12 hours to obtain nano-SnO2 core layer particles; wherein the weight ratio of SnCl4·5H2O to polyvinyl pyrrolidone is 100:2, and the ammonia concentration is 25-28%; Step 2: Using the nano-SnO2 core layer particles prepared in step 1 as a matrix, zirconium tetrachloride and deionized water as precursors, in a hot-wall ALD reaction chamber, the deposition temperature is 260°C, the chamber pressure is 4 Torr, and ZrCl4 and H2O vapors are alternately introduced. The pulse time of ZrCl4 and H2O is 0.2 seconds, and nitrogen is purged for 8 seconds between each pulse. The number of cycles is 120 (ZrCl4 vapor pulse, nitrogen purge, then H2O vapor pulse, and then nitrogen purge, which constitutes one cycle). Finally, annealing is performed at 300°C in an argon atmosphere for 1 hour to obtain SnO2-ZrO2 core-shell particles. The gas flow rates of ZrCl4 vapor and H2O vapor are 0.01-0.05 g / min and 0.1-0.3 g / min, respectively. Step 3, disperse the SnO2-ZrO2 core-shell particles in a 0.1-0.5 mol / L HCl solution, ultrasonically treat for 30 minutes, add aniline monomer, and stir for 8-12 minutes under nitrogen protection; add ammonium persulfate dropwise, react at a water bath temperature of 35°C for 5 hours, then separate by centrifugation, wash with deionized water to neutrality, and finally vacuum dry at 60°C to constant weight to obtain cross-linked polyaniline-coated SnO2-ZrO2 particles; wherein the weight ratio of SnO2-ZrO2 core-shell particles, aniline monomer, and ammonium persulfate is 100:130:22.

[0023] The preparation method of the enhancer is as follows: Step a, mixing glass flakes with an etching solution, etching for 15 minutes at 25°C and a stirring speed of 400 rpm (magnetic stirring), rinsing with deionized water to a pH of 6.5-7.5, and vacuum drying at a temperature of 100-120°C to constant weight; the etching solution comprises the following components by volume percentage: 8% hydrofluoric acid (concentration of 40%), 2% sulfuric acid (concentration of 98%), and 10% ethylene glycol. The etching solution also includes hexadecyltrimethylammonium bromide at a mass concentration of 1.5g / L, and the balance is water. The weight-to-volume ratio of glass flakes to etching solution is 1:10g / mL; Step b, mixing the glass flakes after the etching treatment in step a with an activation solution, activating them at 60° C. for 40 minutes, washing with deionized water, washing with alcohol to remove impurities, and pre-drying in a 50° C. oven for 20 minutes, wherein the activation solution comprises the following components by weight percentage: 30% H2O2:3%, 65% nitric acid 1.0%, and the balance water, and the weight-to-volume ratio of the glass flakes to the activation solution is 1:10 g / mL; Step c, placing the glass flakes activated in step b in a hydrolysis solution, ultrasonically dispersing for 10 minutes, cyclically immersing at a pressure of -0.09 MPa for 3 times, each time for 10 minutes, then reacting at 45-55°C for 8-10 hours, centrifuging, washing with tetrahydrofuran 3 times to remove unreacted materials, and vacuum drying at 80°C to constant weight to obtain modified glass flakes, wherein the hydrolysis solution comprises, by weight percentage, 6% KH570, 18% acetic acid-sodium acetate buffer (pH 4.5), 0.05% ammonium fluoride, and the balance is anhydrous ethanol; Step d, mixing the modified glass flakes obtained in step c with nano-SiO2, dispersant, and ethanol, using a ball mill with a ball-to-material ratio of 5-8:1, a rotation speed of 250-350rpm, and a ball milling time of 1.5-2.5 hours, and then spray drying with a drying inlet temperature of 180-200°C and an outlet temperature of 80-90°C to obtain a reinforcing agent, wherein the weight ratio of modified glass flakes, nano-SiO2, and dispersant (sodium polyacrylate) is 75:25:0.2, and the weight-to-volume ratio of modified glass flakes to ethanol is 8g / 4ml.

[0024] The above-mentioned method for preparing the high-stability alkaline battery positive electrode composite anti-corrosion conductive material is as follows: PVDF is added to the solvent N-methylpyrrolidone, with the weight ratio of PVDF to NMP being 1:8-10, and stirred to dissolve. Then, graphene, carbon nanotubes, anti-corrosion composite materials, and reinforcing agents are added. The mixture is first mixed at a low speed (500 rpm for 30 minutes), then dispersed at a high speed (2000 rpm for 1 hour), vacuum degassing treatment (-0.095 MPa for 30 minutes), and passed through a 200-mesh sieve to remove agglomerated particles. Example 2 A high-stability alkaline battery positive electrode composite anti-corrosion conductive material, comprising the following components by weight: 40 parts of graphene, 30 parts of carbon nanotubes, 15 parts of a binder, 20 parts of an anti-corrosion composite material, and 8 parts of a reinforcing agent; The method for preparing the anti-corrosion composite material comprises the following steps: Step 1: dissolving tin tetrachloride in deionized water to prepare a 0.2 mol / L solution; adding polyvinyl pyrrolidone; and adjusting the pH to 8-10 with aqueous ammonia; stirring at 300 rpm at 90° C. for 2 hours; and performing the purification process as in Example 1; wherein the weight ratio of SnCl4·5H2O to polyvinyl pyrrolidone (PVP, molecular weight 55,000) is 1:2, and the aqueous ammonia concentration is 25-28%; Step 2: The deposition temperature was 200° C., the chamber pressure was 2 Torr, and ZrCl 4 and H 2 O vapors were introduced alternately. The pulse duration of ZrCl 4 and H 2 O was 0.1 second, and nitrogen was purged for 5-10 seconds between each pulse. The number of cycles was 50, wherein the gas flow rates of ZrCl 4 vapor and H 2 O vapor were 0.01-0.05 g / min and 0.1-0.3 g / min, respectively. The rest of the process was the same as in Example 1. Step 3, disperse the SnO2-ZrO2 core-shell particles in a 0.1-0.5 mol / L HCl solution, ultrasonically treat for 30 minutes, add aniline monomer, and stir for 8-12 minutes under nitrogen protection; add ammonium persulfate dropwise, react at a water bath temperature of 30°C for 4 hours, then separate by centrifugation, wash with deionized water to neutrality, and finally dry in vacuo at 60°C to constant weight to obtain cross-linked polyaniline-coated SnO2-ZrO2 particles; wherein the weight ratio of SnO2-ZrO2 core-shell particles, aniline monomer, and ammonium persulfate is 100:160:25.

[0025] The preparation method of the enhancer is as follows: Step a: mixing glass flakes with an etching solution, etching for 10 minutes at 30°C and a stirring speed of 300 rpm (magnetic stirring), rinsing with deionized water until the pH reaches 6.5-7.5, and vacuum drying at a temperature of 100-120°C to constant weight; the etching solution comprises the following components by volume: 5% hydrofluoric acid (concentration of 40%), 3% sulfuric acid (concentration of 98%), and 8% ethylene glycol. The etching solution also includes hexadecyltrimethylammonium bromide at a mass concentration of 1g / L, and the balance is water. The weight-to-volume ratio of glass flakes to etching solution is 1:8g / mL; Step b, the activation solution comprises the following components by weight percentage: 30% H2O2: 2%, 65% nitric acid: 1.5%, and the balance is water. The weight-to-volume ratio of glass flakes to activation solution is 1:12 g / mL. The rest is the same as in Example 1; Step c, the hydrolyzate comprises, by weight percentage, 5% KH570, 20% acetic acid-sodium acetate buffer (pH 4.5), 0.05% ammonium fluoride, and the balance anhydrous ethanol; the rest is the same as in Example 1; In step d, the weight ratio of modified glass flakes, nano-SiO2, and dispersant (sodium polyacrylate) is 70:30:0.1, the weight volume ratio of modified glass flakes to ethanol is 8g / 3ml, and the rest is the same as Example 1.

[0026] The preparation method of the above-mentioned high-stability alkaline battery positive electrode composite anti-corrosion conductive material is the same as that of Example 1.

[0027] Example 3 A high-stability alkaline battery positive electrode composite anti-corrosion conductive material, comprising the following components by weight: 50 parts of graphene, 20 parts of carbon nanotubes, 8 parts of a binder, 30 parts of an anti-corrosion composite material, and 12 parts of a reinforcing agent; The method for preparing the anti-corrosion composite material comprises the following steps: Step 1: dissolving tin tetrachloride in deionized water to prepare a 0.5 mol / L solution; adding polyvinyl pyrrolidone; and adjusting the pH to 8-10 with aqueous ammonia; stirring at 500 rpm at 70°C for 4 hours; and performing the purification process as in Example 1; wherein the weight ratio of SnCl4·5H2O to polyvinyl pyrrolidone (PVP, molecular weight 55,000) is 1:0.5, and the aqueous ammonia concentration is 25-28%; Step 2: The deposition temperature was 300° C., the chamber pressure was 5 Torr, and ZrCl4 and H2O vapors were introduced alternately. The pulse duration of ZrCl4 and H2O was 0.3 seconds, and nitrogen was purged for 10 seconds between each pulse. The number of cycles was 200, wherein the gas flow rates of ZrCl4 vapor and H2O vapor were 0.01-0.05 g / min and 0.1-0.3 g / min, respectively. The rest of the process was the same as in Example 1. Step 3, disperse the SnO2-ZrO2 core-shell particles in a 0.1-0.5 mol / L HCl solution, ultrasonically treat for 30 minutes, add aniline monomer, and stir for 8-12 minutes under nitrogen protection; add ammonium persulfate dropwise, react at a water bath temperature of 40°C for 4.5 hours, then separate by centrifugation, wash with deionized water to neutrality, and finally vacuum dry at 60°C to constant weight to obtain cross-linked polyaniline-coated SnO2-ZrO2 particles; wherein the weight ratio of SnO2-ZrO2 core-shell particles, aniline monomer, and ammonium persulfate is 100:100:20.

[0028] The preparation method of the enhancer is as follows: Step a: mixing glass flakes with an etching solution, etching for 20 minutes at 20°C and a stirring speed of 500 rpm (magnetic stirring), rinsing with deionized water until the pH is 6.5-7.5, and vacuum drying at a temperature of 100-120°C to constant weight; the etching solution comprises the following components by volume: 10% hydrofluoric acid (concentration of 40%), 1% sulfuric acid (concentration of 98%), and 12% ethylene glycol. The etching solution also includes hexadecyltrimethylammonium bromide at a mass concentration of 2g / L, and the balance is water. The weight-to-volume ratio of glass flakes to etching solution is 1:12g / mL; Step b, the activation solution comprises the following components by weight percentage: 30% H2O2: 4%, 65% nitric acid: 0.5%, and the balance is water. The weight-to-volume ratio of glass flakes to activation solution is 1:8 g / mL. The rest is the same as in Example 1; Step c, the hydrolyzate comprises, by weight percentage, 7% KH570, 15% acetic acid-sodium acetate buffer (pH 4.5), 0.05% ammonium fluoride, and the balance anhydrous ethanol; the rest is the same as in Example 1; In step d, the weight ratio of modified glass flakes, nano-SiO2, and dispersant (sodium polyacrylate) is 80:20:0.3, the weight volume ratio of modified glass flakes to ethanol is 7g / 3ml, and the rest is the same as Example 1.

[0029] The preparation method of the above-mentioned high-stability alkaline battery positive electrode composite anti-corrosion conductive material is the same as that of Example 1.

[0030] Example 4 A high-stability alkaline battery positive electrode composite anti-corrosion conductive material comprises the following components by weight: 48 parts of graphene, 25 parts of carbon nanotubes, 7 parts of PVDF binder, 45 parts of anti-corrosion composite material, and 18 parts of reinforcing agent. The remaining components are the same as those in Example 1.

[0031] Comparative Example 1 A high-stability alkaline battery positive electrode composite anti-corrosion conductive material, comprising the following components by weight: 45 parts of graphene, 25 parts of carbon nanotubes, 10 parts of PVDF binder, 25 parts of anti-corrosion composite material, and 10 parts of reinforcing agent; The method for preparing the anti-corrosion composite material comprises the following steps: Step 1: dissolving tin tetrachloride (SnCl4·5H2O) in deionized water to prepare a 0.3 mol / L solution; adding polyvinyl pyrrolidone, and adjusting the pH to 8-10 with ammonia water; stirring at 400 rpm at 80°C for 3 hours; washing by centrifugation, washing with deionized water three times and ethanol once, centrifuging at 8000 rpm for 10 minutes each; and finally vacuum drying at 60°C for 12 hours to obtain nano-SnO2 core layer particles; wherein the weight ratio of SnCl4·5H2O to polyvinyl pyrrolidone is 100:2, and the ammonia concentration is 25-28%; In step 2, the nano-SnO2 core-layer particles prepared in step 1 were used as a matrix, and zirconium tetrachloride and deionized water were used as precursors. In a hot-wall ALD reaction chamber, the deposition temperature was 260°C and the chamber pressure was 4 Torr. ZrCl4 and H2O vapor were alternately introduced, with pulse durations of 0.2 seconds for each ZrCl4 and H2O, and a nitrogen purge of 8 seconds between each pulse. The number of cycles was 120 (one cycle consisted of a ZrCl4 vapor pulse, followed by a nitrogen purge, followed by an H2O vapor pulse, and then a nitrogen purge). Finally, the particles were annealed at 300°C for 1 hour in an argon atmosphere to obtain SnO2-ZrO2 core-shell particles. The flow rates of ZrCl4 vapor and H2O vapor were 0.01-0.05 g / min and 0.1-0.3 g / min, respectively. The remaining conditions were the same as in Example 1.

[0032] Comparative Example 2 A high-stability alkaline battery positive electrode composite anti-corrosion conductive material, wherein the reinforcing agent is nano-silicon dioxide, and the rest is the same as in Example 1.

[0033] Comparative Example 3 A high-stability alkaline battery positive electrode composite anti-corrosion conductive material, wherein the reinforcing agent is nano-silicon dioxide, and the rest is the same as that of comparative example 1.

[0034] Prepare alkaline batteries: The high-stability alkaline battery positive electrode composite anti-corrosion conductive material obtained in Examples 1-4 and Comparative Examples 1-3 was evenly coated onto nickel foam and uniformly pressed using a double-roll mill to produce a positive electrode sheet. A negative electrode zinc paste was prepared by mixing 80 parts zinc powder, 5 parts zinc oxide, 15 parts 30% KOH electrolyte (saturated with ZnO), and 5 parts binder into a paste. The zinc paste was poured into a nickel-plated steel shell, inserted with copper nails, and compacted. The electrolyte was prepared as a 7-9 mol / L KOH solution (containing 0.5-1% ZnO) with 0.1% In(OH)3 as a corrosion inhibitor. A multilayer composite separator (cellulose / polypropylene non-woven fabric) was used, impregnated with the electrolyte, and pre-wetted for 24 hours. Battery assembly: steel shell (negative electrode) → zinc paste → pre-wet separator → positive electrode sheet → nickel cap (positive electrode current collector), and then sealed to produce the alkaline battery.

[0035] Pulse discharge test: Tests the discharge cycle of alkaline batteries at 1.5W-2s / 0.65W-28s, 5m / h, 24h / d, EV: 1.05V.

[0036] Duration test in high current discharge mode: The discharge duration of alkaline batteries was tested under the conditions of 3.9Ω, 24h / d, EV: 0.8V (h). The test results are shown in Table 1.

[0037] Table 1. Test results As can be seen in Table 1, the alkaline batteries made from the corrosion-resistant conductive materials of Examples 1-4 outperformed those of Comparative Examples 1-3 in all aspects. In Comparative Example 1, the SnO2-ZrO2 core-shell particles lacked the physical barrier and passivation protection of polyaniline, allowing the electrolyte (KOH) to gradually penetrate the core layer, causing corrosion and dissolution of the SnO2 and accelerated loss of active material. In Comparative Example 2, due to the lack of modification, the nano-SiO2 had poor interfacial bonding with the PVDF matrix. The coating cracked after repeated expansion and contraction during charge and discharge, causing active material to shed, resulting in rapid capacity decay. In Comparative Example 3, the lack of an anti-corrosion barrier and insufficient mechanical strength of the coating led to electrolyte penetration and active material detachment, exacerbating capacity loss. Thus, by employing the technical solution of the present invention, the rational proportioning and preparation process of polyaniline, core-shell particles, and reinforcing agent achieves comprehensive improvements in the material's corrosion resistance, conductivity, and stability, thereby enhancing the overall performance and service life of the battery.

[0038] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0039] Although the embodiments of the present application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A high-stability alkaline battery positive electrode composite anti-corrosion conductive material and a preparation method thereof, characterized in that: The composition comprises the following components by weight: 40-50 parts of graphene, 20-30 parts of carbon nanotubes, 8-15 parts of binder, 20-30 parts of anti-corrosion composite material, and 8-12 parts of reinforcing agent; The method for preparing the anti-corrosion composite material comprises the following steps: Step 1: dissolving tin tetrachloride in deionized water to prepare a 0.2-0.5 mol / L solution, adding polyvinyl pyrrolidone, adjusting the pH to 8-10, reacting for 2-4 hours, and purifying to obtain nano-SnO2 core layer particles; Step 2: Using the nano-SnO2 core layer particles prepared in step 1 as a matrix, zirconium tetrachloride and deionized water as precursors, at a temperature of 200-300°C and a pressure of 2-5 Torr, alternately introducing ZrCl4 and H2O vapor for deposition to obtain SnO2-ZrO2 core-shell particles; Step 3: Disperse the SnO2-ZrO2 core-shell particles in HCl solution, ultrasonically treat, add aniline monomer and ammonium persulfate, and react for 4-5 hours at a water bath temperature of 25-40°C to obtain cross-linked polyaniline-coated SnO2-ZrO2.

2. The high-stability alkaline battery positive electrode composite anti-corrosion conductive material according to claim 1, characterized in that: In step 1, the weight ratio of SnCl4 to polyvinyl pyrrolidone is 1:0.5-2, and the concentration of ammonia water is 25-28%.

3. The high-stability alkaline battery positive electrode composite anti-corrosion conductive material according to claim 1, characterized in that: In step 2, the gas flow rates of ZrCl4 vapor and H2O vapor are 0.01-0.05 g / min and 0.1-0.3 g / min, respectively.

4. The high-stability alkaline battery positive electrode composite anti-corrosion conductive material according to claim 1, characterized in that: In step 3, the weight ratio of SnO2-ZrO2 core-shell particles, aniline monomer, and ammonium persulfate is 100:100-160:20-25.

5. The high-stability alkaline battery positive electrode composite anti-corrosion conductive material according to claim 1, characterized in that: The preparation method of the enhancer is as follows: Step a, mixing the glass flakes with the etching solution, etching for 10-20 minutes at 20-30°C and a stirring speed of 300-500 rpm, and then washing and drying; Step b, mixing the glass flakes after the etching treatment in step a with an activation solution, activating them at 55-65° C. for 35-45 minutes, and then washing and drying them; Step c, placing the glass flakes activated in step b in a hydrolyzate, ultrasonically dispersing for 10 minutes, cyclically immersing at a pressure of -0.09 MPa for 2-3 times, each time for 10 minutes, then reacting at 45-55° C. for 8-10 hours, and purifying to obtain modified glass flakes; Step d: mixing the modified glass flakes obtained in step c with nano-SiO2, a dispersant, and ethanol, ball-milling, and drying to obtain a reinforcing agent.

6. The high-stability alkaline battery positive electrode composite anti-corrosion conductive material according to claim 5, characterized in that: In step a, the etching solution includes the following components in volume percentage: 5-10% hydrofluoric acid, 1-3% sulfuric acid, and 8-12% ethylene glycol. The concentration of hydrofluoric acid is 40%, and the concentration of sulfuric acid is 98%. The etching solution also includes hexadecyltrimethylammonium bromide with a mass concentration of 1-2g / L, and the balance is water. The weight-to-volume ratio of glass flakes to etching solution is 1:8-12g / mL.

7. The high-stability alkaline battery positive electrode composite anti-corrosion conductive material according to claim 5, characterized in that: The activation solution in step b includes the following components by weight percentage: 30% H2O2: 2-4%, 65% nitric acid 0.5-1.5%, and the balance is water. The weight-to-volume ratio of glass flakes to activation solution is 1:8-12 g / mL.

8. The high-stability alkaline battery positive electrode composite anti-corrosion conductive material according to claim 5, characterized in that: The hydrolyzate in step c comprises 5-7% KH570, 15-20% buffer, 0.05% ammonium fluoride, and the balance is anhydrous ethanol.

9. The high-stability alkaline battery positive electrode composite anti-corrosion conductive material according to claim 5, characterized in that: In step d, the weight ratio of modified glass flakes, nano-SiO2, and dispersant is 70-80:20-30:0.1-0.3, and the weight volume ratio of modified glass flakes to ethanol is 7-8g / 3-5ml.

10. The method for preparing the high-stability alkaline battery positive electrode composite anti-corrosion conductive material according to any one of claims 1 to 9, characterized in that: The binder is added to the solvent N-methylpyrrolidone, with the weight ratio of PVDF to NMP being 1:8-10, and stirred to dissolve. Then, graphene, carbon nanotubes, anti-corrosion composite materials, and reinforcing agents are added and mixed evenly to obtain the product.

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