Preparation and application method of a gel material for inhibiting zinc dendrite

Abstract

The present application relates to zinc-nickel battery technology, and aims to provide a preparation and application method of a gel material for inhibiting zinc dendrite. The preparation method comprises: dropping a PVA solution into a PAA solution, stirring, polymerizing, and spray drying to obtain a gel powder of PAA-PVA copolymer; synchronously dropping the PAA solution and the PVA solution into an amphoteric surfactant solution to obtain an amphoteric surfactant modified gel solution; after spray drying, obtaining amphoteric surfactant modified PAA-PVA, which is the gel material for inhibiting zinc dendrite, and is used as a binder for positive and negative electrode preparation and battery assembly. The present application starts from three aspects of reducing the activity of the metal zinc / electrolyte interface and the reaction activity of zincate ions in the zinc-nickel gel battery and strengthening hydrogen escape to inhibit the occurrence of zinc dendrite; the inhibiting effect of the surfactant on the occurrence of dendrite and the inhibiting effect of the gel electrolyte on the growth of dendrite are mutually complementary to avoid zinc electrode self-discharge and improve the reliability and use effect of the zinc-nickel battery.

Description

Technical Field

[0001] This invention relates to zinc-nickel battery technology, specifically to a method for preparing a gel material that inhibits zinc dendrite formation and its application in zinc-nickel batteries. Background Technology

[0002] Traditional zinc-nickel batteries are alkaline secondary batteries that use zinc oxide as the negative electrode active material, nickel hydroxide as the positive electrode active material, and are constructed by stacking zinc negative electrode, intermediate separator, and nickel electrode in sequence, with potassium hydroxide aqueous solution as the electrolyte. Zinc-nickel batteries are not only used in small loads such as household appliances, electric toys, and electric doors and windows, but also have good commercial prospects in fields with high safety requirements, such as electric bicycles, electric vehicles, high-speed rail power supplies, and backup power supplies for energy storage base stations.

[0003] Zinc oxide is abundant, and zinc-nickel batteries offer a significant cost advantage over lead-acid and lithium-ion batteries, while also being environmentally friendly and safe. Although zinc-nickel batteries have been around for nearly a century, a key problem—the tendency for zinc dendrites to form on the negative electrode, leading to poor cycle performance—remains unresolved.

[0004] During discharge, the zinc in the zinc electrode is oxidized, forming zinc oxide or zinc hydroxide. Since the electrolyte in a zinc-nickel battery is a high-concentration KOH solution, the zinc oxide or zinc hydroxide is converted to zincate (Zn(OH)₄) in the alkaline solution. 2－ Dissolution occurs during the charging of zinc-nickel batteries. The zinc electrode is controlled by liquid-phase diffusion mass transfer, resulting in a lower ion concentration near the electrode surface and significant concentration polarization. This leads to the dissolution of Zn(OH)₄ in the electrolyte. 2－ Zinc is easily reduced at the dendritic region, forming dendritic dendrites. As charging and discharging proceed, zinc deposition at the electrode dendrites accelerates and develops into dendrites. Additionally, uneven thickness distribution on the zinc electrode surface due to manufacturing process inaccuracies is also a contributing factor to dendrite formation. Once formed, zinc dendrites detach from the electrode, causing a decrease in capacity; if they continue to grow, they can pierce the separator and, upon contact with the positive electrode, create a short circuit, leading to battery failure.

[0005] Factors influencing zinc dendrite formation mainly include current density and the concentration of zincates in the electrolyte. During zinc electrode charging, when the current density is below 30% of the maximum limiting current, zinc dendrites primarily grow from the root, forming whisker-like dendrites with weak penetration ability; the membrane can block these whisker-like dendrites. However, when the current exceeds the limiting current, zinc deposition is restricted by the diffusion process, and zinc mainly deposits at the dendrite tips, exhibiting a staghorn-like growth pattern. Tiny dendrites can penetrate the micropores in the membrane, causing short circuits. When the current density is between these two limits, zinc deposition is faster, leading to breakage of the interfacial membrane at multiple points, generating numerous growth points. Simultaneously, whisker-like dendrites can still form in areas where the interfacial membrane remains intact, resulting in a very rough zinc interface from the formation of various types of zinc dendrites. The formation of zinc dendrites is closely related to the zincate content in the electrolyte; a low zincate concentration makes zinc dendrite formation more likely, and factors hindering zincate transport will exacerbate its formation. Therefore, constructing a high-density, uniform zincate concentration interface layer becomes a key factor in controlling zinc dendrite formation.

[0006] Hydrogel electrolytes, such as potassium polyacrylate, are highly effective for constructing high-concentration zincate interface layers. However, single-component gel electrolytes have significant drawbacks. For example, hydrogen gas is generated during charging as a side reaction at the zinc electrode, reducing material and ion conductivity and decreasing the passivation effect on active sites prone to zinc dendrite formation. Furthermore, the formation of large-area bubbles within the hydrogel electrolyte leads to uneven current density distribution, which in turn promotes zinc dendrite development. Therefore, traditional single-component gels can only suppress dendrite formation in cases of highly uniform zinc electrodes without bubble generation; they are unsuitable for large-scale industrial production of zinc electrodes with surface defects and the actual operating conditions involving hydrogen bubble formation. Although single-component gels can also construct high-density zincate interface layers, bubble formation causes separation between the gel electrolyte and the zinc electrode, resulting in the loss of passivation function. Therefore, the performance of single-component gels is unsatisfactory, and the reliability of single-component gel zinc-nickel batteries is not high.

[0007] Because polyvinyl alcohol (PVA) has a negative charge and polyacrylic acid (PAA) has a positive charge, an electrostatic force is formed between these two molecules when they are mixed. This force promotes the formation of a network structure and a surface with a regularly distributed dipole moment, attracting polar molecules. PAA and PVA can self-assemble into a network structure, and the linearity of PAA and PVA makes this network structure flexible. Therefore, the copolymer of PAA and PVA (PAA-PVA) can absorb a large amount of polar liquids such as potassium hydroxide solution, altering the surface properties of the polymer and becoming a gel electrolyte. Modifying the gel electrolyte with surfactant molecules capable of passivating zinc active sites not only increases the zincate concentration at the interface layer but also passivates the zinc active sites. Furthermore, the hydrophobic ends of the surfactant molecules aggregate to form gas-conducting channels, preventing uneven current density caused by bubble generation, and especially preventing zinc dendrite formation under overcharge and discharge, thereby improving the reliability of zinc-nickel batteries.

[0008] Traditional high-concentration KOH solutions for Zn anodes are prone to pitting corrosion during charge and discharge, increasing ion conduction inhomogeneity and increasing the likelihood of dendrite formation. In contrast, Zn deposition / dissolution reactions in gel electrolytes tend to occur across the entire electrode surface rather than focusing on a single point, resulting in more uniform Zn deposition. The presence of surfactant molecules in the gel increases the affinity between the gel and the solid surface and enhances gas escape capabilities. This not only leads to a more uniform zincate concentration at the interface layer but also allows for a hydrophilic-hydrophobic balance to be achieved by varying the type, proportion, and position of hydrophilic or hydrophobic groups in the molecular structure. This passivates zinc active sites, increases hydrogen escape capabilities, ensures the affinity between the gel and metallic zinc, and inhibits dendrite formation.

[0009] When surfactant molecules in a gel electrolyte adsorb onto the surface of metallic zinc, forming a dense adsorption layer, they impede current flow, leading to an increase in overpotential, a decrease in the electrode reaction rate, and inhibition of dendrite formation, resulting in a bright, dense, and smooth zinc deposition layer. The hydrophilic ends of surfactant molecules typically possess unbonded lone pairs of electrons, while the electronic configuration of metallic zinc is d... 10 That is, the d sublayer is fully filled, through sp 3 Hybridization and ligand formation result in tetrahedral coordination compounds, creating multilayered chemisorption layers. The spatial configuration of the gel electrolyte ligands is a key factor in stabilizing the adsorption layer and passivating the zinc dendrite front. Studies have shown that adding cationic surfactants such as hexadecyltriethylammonium bromide (CTAB) to the electrolyte can react with zincate ions (Zn(OH)₄). 2－ Formation of multi-component ion-paired compounds (CTAB) + )2Zn(OH)4 2－This significantly increases the overpotential and reduces dendrite formation. The addition of anionic surfactants such as citrate and sodium gluconate forms [ZnHcit]. － and [ZnGlu] + This also increases the overpotential and inhibits the formation of zinc dendrites. When the surfactant is adsorbed onto the surface of metallic zinc by electrostatic forces, forming a monolayer adsorption, the charged state of the zinc metal surface and the cations in the electrolyte system form an electric double layer. At the same time, the hydrophobic ends of the surfactant molecular fragments aggregate in the gel, forming gas diffusion channels.

[0010] Amphoteric surfactants are surfactants that possess both anionic and cationic hydrophilic groups, such as betaine surfactant R-N. + (CH3)2—CH2—CH2—COO - It exhibits excellent stability and strong affinity for divalent cations. When the negatively charged COO of the amphoteric surfactant... - PAA grafted onto the positively charged PVA-PAA copolymer, with its positively charged N-terminus... + (CH3)2 can react with zincate ions Zn(OH)4 2－ Formation of multi-component ion-paired compounds (N + (CH3)2)2Zn(OH)4 2－ This significantly increases the overpotential and reduces dendrite formation. However, when the positively charged N-terminus of the amphoteric surfactant... + (CH3)2 is grafted onto the negatively charged PVA in the PAA-PVA copolymer, while its negatively charged COO-terminus... - It can react with zincate ions Zn(OH)4 2－ Formation of the complex ion [ZnCOO] + It can also increase overpotential and reduce dendrite formation. Therefore, amphoteric surfactants modified gel electrolytes have a good ability to passivate zinc active sites.

[0011] After grafting amphoteric surfactants onto the gel electrolyte, numerous hydroxyl, carboxyl, and amine or ammonium groups are formed, which can chelate and coordinate with zinc ions, effectively reducing Zn. 2+ The activity of water molecules bound around the solvation shell enhances the ion confinement effect to suppress side reactions and dendrite formation. At the same time, the aggregation of the hydrophobic ends of the amphoteric surfactant forms a gas diffusion channel, enabling uniform deposition and dissolution of zinc during charging and discharging.

[0012] However, traditional methods for suppressing dendrite growth, such as adding surfactants to the electrolyte or using single-component gels, only inhibit dendrite growth on the surface of flat, ideal electrodes. These methods are insufficient for situations with defects or gas films forming on the positive and negative electrodes during battery charging and discharging. Therefore, under actual charging and discharging conditions, the traditional methods of adding surfactants and using single-component gel electrolytes have limited effectiveness in suppressing dendrite growth on the zinc electrode in zinc-nickel gel batteries. Summary of the Invention

[0013] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a method for preparing and applying a gel material for suppressing zinc dendrites.

[0014] To solve the technical problem, the technical solution of the present invention is as follows:

[0015] A method for preparing a gel material for suppressing zinc dendrites is provided, comprising the following steps:

[0016] (1) Take 1-10g of polyacrylic acid (PAA) powder with a molecular weight of 5000-100000, dissolve it in 100mL of deionized water at 80-100℃, and disperse it by ultrasonic vibration for 30 minutes to obtain PAA solution; take 1-10g of polyvinyl alcohol (PVA) powder with a molecular weight of 5000-100000, dissolve it in 100mL of deionized water at 80-100℃, and disperse it by ultrasonic vibration for 30 minutes to obtain PVA solution;

[0017] (2) The PVA solution is added dropwise to the PAA solution, and after stirring and polymerization for 0.5 to 2.0 h, a gel solution is obtained; after spray drying, PAA-PVA copolymer powder is obtained, referred to as gel powder;

[0018] (3) Take 1-10g of amphoteric surfactant, dissolve it in 100mL of deionized water at 80-100℃, and disperse it by ultrasonic vibration for 30 minutes to obtain a surfactant solution;

[0019] (4) Prepare PAA solution and PVA solution again according to the method in step (1), and add them dropwise to the amphoteric surfactant solution. The mass ratio of amphoteric surfactant, PAA and PVA is 1:(1~5):(1~2). After stirring and reacting at 80~100℃ for 0.5~2.0h, an amphoteric surfactant modified gel solution is obtained. After spray drying, amphoteric surfactant modified PAA-PVA is obtained, which is the gel material used to inhibit zinc dendrites.

[0020] As a preferred embodiment of the present invention, the ultrasonic vibration frequency range in each step is 25 to 130 kHz.

[0021] As a preferred embodiment of the present invention, the stirring speed in each step is 50 to 1000 rpm.

[0022] As a preferred embodiment of the present invention, the amphoteric surfactant molecule has both acidic and basic groups; wherein the acidic group is a carboxyl group, a sulfonic acid group or a phosphate group, and the basic group is an amino group or a quaternary ammonium group.

[0023] The present invention further provides a method for preparing a zinc electrode using the aforementioned gel material, comprising the following steps:

[0024] (1) Using the gel material as a binder, zinc oxide, acetylene black, and the binder are taken in a mass ratio of 7:2:1, and an appropriate amount of deionized water is added. The mixture is then mechanically ground and mixed to form a paste. The paste is applied to the upper and lower surfaces of the galvanized copper mesh and dried at 100 kg / cm². 2 Zinc electrodes are obtained by pressing them under pressure to form a mold.

[0025] (2) The gel material and gel powder are sequentially sprayed on one side of the zinc electrode by electrostatic spraying to form a double-layer spraying structure, thereby obtaining a zinc electrode coated with composite gel material.

[0026] As a preferred embodiment of the present invention, in the double-layer spraying structure of the zinc electrode, the thickness of the gel material layer is 2-20 μm, and the thickness of the gel powder layer is 6-60 μm.

[0027] The present invention also provides a method for preparing a composite gel zinc-nickel battery capable of suppressing zinc dendrites using the aforementioned zinc electrode, comprising the following steps:

[0028] (1) Take nickel hydroxide, nickel carbonyl powder and gel material in a mass ratio of 8:1:1, add an appropriate amount of deionized water and grind to form a paste; then apply it to the nickel foam, and after drying, 100 kg / cm 2 Nickel electrodes are obtained by pressing them under pressure to form a nickel electrode.

[0029] (2) A gel material with a thickness of 2 to 20 μm is electrostatically sprayed onto one side of the nickel electrode to obtain a nickel electrode coated with gel material;

[0030] (3) Stack the coatings of the zinc electrode and the nickel electrode facing each other, and then heat them at 90-100℃ and 100 kg / cm². 2 Under pressure, hot pressing is used to obtain a composite gel material battery cell;

[0031] (4) Place the composite gel material cell in the battery container and add 3-9 mol / L KOH electrolyte; let it stand at 60°C for 3-12 hours for aging treatment to obtain a zinc-nickel battery based on the modified composite gel.

[0032] The present invention also provides a zinc-nickel battery, comprising a battery container consisting of a negative electrode shell and a positive electrode shell, wherein the positive and negative electrode shells are insulated and isolated from each other by a sealing ring;

[0033] The composite gel material battery cell with a sandwich structure inside the battery container is formed by hot pressing zinc electrodes and nickel electrodes stacked facing each other with their respective coatings. The coating on the zinc electrode includes gel material and gel powder, and the coating on the nickel electrode includes gel material. The gel material is PAA-PVA copolymer powder modified with amphoteric surfactant, and the gel powder is unmodified PAA-PVA copolymer powder. The multilayer coating materials together form a composite gel matrix inside the composite gel material battery cell.

[0034] A cavity is left between the upper part of the battery cell and the outer shell. Electrolyte is injected into the cavity through a sealing ring using a syringe. After the composite gel matrix inside the battery cell absorbs the electrolyte, it forms a composite gel electrolyte.

[0035] As a preferred embodiment of the present invention, the electrolyte is a 3-12 mol / L KOH solution.

[0036] As a preferred embodiment of the present invention, the thickness of the composite gel matrix inside the composite gel material cell is 8 to 80 μm.

[0037] Description of the invention principle:

[0038] 1. This invention involves electrostatically spraying component B of a polyacrylic acid (PAA) and polyvinyl alcohol (PVA) copolymer modified with an amphoteric surfactant, along with component A of the PAA and PVA copolymer, onto a zinc electrode, thus connecting component B to the zinc electrode. Similarly, copolymer component B is electrostatically sprayed onto a nickel electrode. The positive and negative electrodes are positioned opposite each other, with a composite gel matrix existing between the electrodes. The cells are then hot-pressed to form a battery cell, which is then placed in a battery container and filled with a potassium hydroxide solution. The composite gel matrix absorbs the alkaline solution and forms a composite gel electrolyte between the positive and negative electrodes. The composite gel composed of components B / A / B effectively inhibits the preferential nucleation and growth of metallic zinc during charging, preventing zinc dendrite formation, thereby obtaining a highly reliable zinc-nickel battery.

[0039] 2. Theoretically, the hydroxyl groups on the PVA segments and the carboxyl groups on the PAA segments of the PAA-PVA copolymer coordinate or chelate with metallic zinc and zincate ions. The gel electrolyte adsorbs onto the metallic zinc, inhibiting zinc dendrite growth. The zincate ions are absorbed by the gel electrolyte, forming a uniform zincate ion interface layer, reducing zinc dendrite formation. In practice, because the zinc electrode potential is more negative than the hydrogen escape potential, although the hydrogen escape overpotential on zinc is high, hydrogen inevitably occurs at some active sites due to zinc hydrolysis. Moreover, during charging and discharging, the zinc electrode is continuously activated, and the number of active centers increases. During charging, the side reaction of water electrolysis occurs, also producing hydrogen. The generated hydrogen forms a local gas film between the gel and the zinc electrode, locally weakening the passivation effect of the gel electrolyte on zinc dendrites and preventing ion conduction, causing uneven ion conduction and actually promoting zinc dendrite formation. In surfactant-modified PVA-PAA gel electrolytes, the aggregation of hydrophobic groups forms gas diffusion channels within the gel electrolyte, which can prevent the formation of a gas film on the zinc metal and gel surface after the generation of hydrogen gas by self-discharge and electrochemical side reactions. This ensures the passivation of zinc metal and the close contact between the zinc metal surface and the gel surface, and inhibits the occurrence and growth of zinc dendrites.

[0040] 3. During the assembly of the battery cell, the binders for the positive and negative electrodes and the modified gel electrolyte matrix in contact with the electrodes have the same composition. During hot pressing, the binders for the positive and negative electrodes fuse with the modified gel matrix layer, and the modified gel matrix layer fuses with the copolymer to form a whole. This establishes a stable gel electrolyte ion conduction system during subsequent electrolyte addition, avoiding poor contact between the gel electrolyte and the electrodes that may occur during electrolyte addition, which could result in free electrolyte at the electrode interface and between the gel electrolyte. The presence of free electrolyte at the electrode interface and between the gel electrolyte will inevitably lead to dendrite formation. Furthermore, during discharge, a zincate ion-depleted region is easily formed, increasing the likelihood of dendrite formation.

[0041] 4. The reason for using the same modified gel material as the negative electrode as the binder on the positive electrode side is that the positive electrode releases oxygen during over-discharge. If a single-component gel electrolyte is used, similar to the formation of a local hydrogen film on the negative electrode surface, a local oxygen film will form between the positive electrode surface and the gel electrolyte, which will also prevent ion conduction, causing uneven ion conduction and inducing the formation of zinc dendrites. In PAA-PVA, amphoteric surfactants are grafted to form gas diffusion channels within the gel electrolyte, which can prevent the formation of a local gas film on the positive electrode and gel surface during over-discharge, ensuring close contact between the positive electrode surface and the gel surface and inhibiting the formation of zinc dendrites.

[0042] 5. After surfactant modification of the gel, since the hydrophobic end of the surfactant is not conducive to the absorption of polar zincate ions, it is necessary to place a PAA-PVA gel matrix with high absorption capacity between the surfactant-modified gel matrix to improve the absorption capacity of zincate ions. Therefore, a B / A / B structured gel matrix can take into account both gas release and zincate ion absorption, resulting in a better zinc dendrite suppression effect.

[0043] Compared with the prior art, the present invention has the following beneficial effects:

[0044] 1. This invention addresses the inhibition of zinc dendrite formation by reducing the interfacial activity of zinc / electrolyte and the reactivity of zincate ions in zinc-nickel gel batteries, and enhancing hydrogen escape. By modifying the gel electrolyte with a surfactant, a stable adsorption layer can be formed on the zinc surface, reducing water activity, controlling the concentration of zincate ions, forming ultra-large composite ions, utilizing steric hindrance to increase overpotential, and delaying zinc crystal growth. The hydrophobic groups of the surfactant enhance gas escape, reducing current density inhomogeneity and inhibiting dendrite formation.

[0045] 2. This invention overcomes the shortcomings of traditional methods by connecting a surfactant-modified gel electrolyte to the electrode. The hydrophobic ends of the surfactant molecules improve the gas conduction ability of the gel, while the gel electrolyte between the surfactant-modified gel electrolyte plays a role in uniformly distributing zincate ions, increasing the zincate ion concentration, reducing the zincate ion activity, and blocking the transport of O2 from the positive electrode to the negative electrode. This allows the inhibitory effects of the surfactant on dendrite formation and the gel electrolyte on dendrite growth to complement each other and be fully utilized. Furthermore, it avoids self-discharge of the zinc electrode, thus improving the reliability and performance of zinc-nickel batteries compared to existing technologies. Attached Figure Description

[0046] Figure 1 This is a schematic diagram of the composite gel zinc-nickel battery cell and the composite gel zinc-nickel battery structure fabricated in Example 1.

[0047] Figure 2 The cycle performance of the composite gel zinc-nickel battery composed of octadecyl dimethyl betaine modified PAA-PVA and PAA-PVA obtained in Example 2 is compared with the performance stability of commercial zinc-nickel batteries.

[0048] Figure 3 This is a comparison of the discharge curves of the zinc-nickel gel battery with the phosphate betaine surfactant of the present invention obtained in Example 3 and a commercially available zinc-nickel battery before and after being left at 50°C for 30 days.

[0049] Figure 4The image shows a comparison of the dendrite growth of the zinc electrode after 200 charge-discharge cycles using the octadecylpropylhydroxysulfonate-modified composite gel electrolyte obtained in Example 4 and a conventional KOH electrolyte. The left image shows the zinc dendrite morphology on the zinc electrode using the KOH electrolyte, and the right image shows the morphology of the zinc electrode using the octadecylpropylhydroxysulfonate-modified composite gel electrolyte.

[0050] Figure 5 This invention relates to the preparation process of surfactant-modified PAA-PVA composite gel and its zinc-nickel battery.

[0051] Figure 6 The dodecylbenzenesulfonium ammonium modified composite gel zinc-nickel battery obtained in Example 5 of the present invention, compared with the gel zinc-nickel battery using PAA-PVA single-component gel obtained in the comparative example, has an efficiency of 300 mA / cm². 2 Impedance comparison during discharge at current density.

[0052] The figures are labeled as follows: 1-1 Negative electrode casing; 1-2 Zinc negative electrode; 1-3 Polycarboxylate ammonium salt surfactant-modified polyacrylic acid-polyvinyl alcohol copolymer matrix; 1-4 Polyacrylic acid-polyvinyl alcohol copolymer matrix; 1-5 Nickel electrode; 1-6 Negative electrode lead; 1-7 Positive electrode lead; 1-8 Positive electrode casing; 1-9 Sealing ring. 2-1 Composite gel zinc-nickel battery; 2-2 Commercially available zinc-nickel battery. 3-1 Discharge curves of zinc-nickel gel battery and commercially available zinc-nickel battery before being stored at 50℃; 3-2 Discharge curve of zinc-nickel gel battery after being stored at 50℃ for 30 days; 3-3 Discharge curve of commercially available zinc-nickel battery after being stored at 50℃ for 30 days. 6-1 Impedance spectrum of dodecylbenzenesulfonium ammonium modified composite gel zinc-nickel battery; 6-2 Impedance spectrum of PAA-PVA single-component gel zinc-nickel battery. Detailed Implementation

[0053] The present invention will be further described in detail below with reference to specific embodiments:

[0054] Example 1: Zinc-nickel battery based on polycarboxylate ammonium salt surfactant-modified composite gel

[0055] 1 g of polyacrylic acid (PAA) powder with a molecular weight of 5,000 was dissolved in 100 mL of deionized water at 80 °C and dispersed under ultrasonic vibration at a frequency of 25 kHz for 30 minutes to obtain a polyacrylic acid solution (solution A1). 1 g of polyvinyl alcohol (PVA) powder with a molecular weight of 5,000 was dissolved in 100 mL of deionized water at 80 °C and dispersed under ultrasonic vibration at a frequency of 25 kHz for 30 minutes to obtain a polyvinyl alcohol solution (solution B1). Solution B1 was added dropwise to solution A1 while maintaining the temperature at 80 °C; the mixture was stirred at 50 rpm for 0.5 h to obtain a gel solution (gel solution A1). Gel solution A1 was spray-dried to obtain PAA-PVA copolymer powder (gel material A1), which was used as a matrix material in the composite gel electrolyte.

[0056] 1 g of polycarboxylate ammonium salt surfactant ZY-652D dispersant produced by Shanghai Ziyi Chemical Co., Ltd. was dissolved in 100 mL of deionized water at 80 °C and dispersed under ultrasonic vibration at a frequency of 25 kHz for 30 minutes to obtain a surfactant solution (surfactant solution C1). Solutions A1 and B1 were simultaneously added dropwise to surfactant solution C1, and the mixture was stirred at 80 °C for 0.5 h to obtain a polycarboxylate ammonium salt surfactant-modified PAA-PVA gel solution (gel solution B1). The gel solution was spray-dried to obtain a polycarboxylate ammonium salt surfactant-modified PAA-PVA gel material (gel material B1), which was used as another matrix material in the composite gel electrolyte and as a binder for preparing positive and negative electrodes.

[0057] Using gel material B1 as a binder, zinc oxide, acetylene black, and the binder were mixed in a mass ratio of 7:2:1, and distilled water was added. The mixture was then mechanically ground to form a paste. The paste was applied to the upper and lower surfaces of a galvanized copper mesh and dried at 100 kg / cm². 2 The zinc electrode (zinc electrode A1) is obtained by pressing under pressure. Gel material B1 and gel material A1 are sequentially sprayed onto one side of the zinc electrode by electrostatic spraying; wherein the thickness of gel material B1 layer is 2μm and the thickness of gel material A1 layer is 6μm.

[0058] Using gel material B1 as a binder, nickel hydroxide, commercially available carbonyl nickel powder, and gel material B1 were mixed in a mass ratio of 8:1:1, ground with deionized water to form a paste, and then applied to the nickel foam. After drying, the paste was heated to 100 kg / cm³. 2 Under pressure, a nickel electrode (nickel electrode A1) is obtained by pressing. A gel material B1 with a thickness of 2 μm is then sprayed onto one side of the nickel electrode via electrostatic spraying, resulting in a nickel electrode A1 coated with gel material B1. A zinc electrode (zinc electrode A1) coated with both gel material B1 and gel material A1 is then stacked face-to-face with a nickel electrode coated with gel material B1, and subjected to a temperature of 90℃ and 100 kg / cm². 2Under pressure, hot pressing is used to form a composite gel matrix zinc-nickel battery cell (cell A1). The thickness of the composite gel electrolyte matrix layer is 8μm (hot pressing will cause the coating material to be compressed, so this thickness is slightly less than the sum of the coating thicknesses on the two electrodes, and the same applies below).

[0059] The obtained battery cell was placed in a battery container, leaving a cavity between the upper part of the cell and the outer casing. Using a syringe, 3 mol / L KOH electrolyte was added to the cavity between the upper part of the cell and the outer casing through a sealing ring. After the cell absorbed the electrolyte, the syringe was removed, and the battery was aged at 60°C for 3 hours to obtain a composite gel zinc-nickel battery (composite gel battery A1). Figure 1 As shown.

[0060] Example 2: Zinc-nickel battery based on octadecyldimethylbetaine modified composite gel

[0061] 1 g of polyacrylic acid powder with a molecular weight of 10,000 was dissolved in 100 mL of deionized water at 90 °C and dispersed under ultrasonic vibration at a frequency of 100 kHz for 30 minutes to obtain a polyacrylic acid solution (solution A2). 5 g of polyvinyl alcohol powder with a molecular weight of 10,000 was dissolved in 100 mL of deionized water at 90 °C and dispersed under ultrasonic vibration at a frequency of 100 kHz for 30 minutes to obtain a polyvinyl alcohol solution (solution B2). Solution B2 was added dropwise to solution A2 while maintaining a temperature of 90 °C. The mixture was stirred and polymerized at a stirring speed of 500 rpm for 1.0 h to obtain a PAA-PVA gel solution with a higher molecular weight (gel solution A2). Gel solution A2 was spray-dried to obtain PAA-PVA gel powder material (gel material A2).

[0062] 2g of octadecyl dimethyl betaine produced by Shanghai Chuxing Chemical Co., Ltd. was dissolved in 100mL of deionized water at 90℃ and dispersed under ultrasonic vibration at 100kHz for 30 minutes to obtain an octadecyl dimethyl betaine solution (surfactant solution C2). Solutions A2 and B2 were simultaneously added dropwise to surfactant solution C2, and the mixture was stirred at 90℃ for 1.0h to obtain an octadecyl dimethyl betaine-modified PAA-PVA gel solution (gel solution B2). After spray drying, an octadecyl dimethyl betaine-modified PAA-PVA powder gel material (gel material B2) was obtained.

[0063] Using gel material B2 as a binder, zinc oxide, acetylene black, and the binder were mixed in a mass ratio of 7:2:1, and deionized water was added. The mixture was then mechanically ground to form a paste. The paste was applied to the upper and lower surfaces of a galvanized copper mesh and dried at 100 kg / cm². 2The zinc electrode (zinc electrode A2) is obtained by pressing under pressure. Gel material B2 and gel material A2 are sequentially sprayed onto one side of the zinc electrode by electrostatic spraying; wherein the thickness of gel material B2 layer is 10μm and the thickness of gel material A2 layer is 20μm.

[0064] Nickel hydroxide, commercially available nickel carbonyl powder, and gel material B2 were ground into a paste with deionized water at a mass ratio of 8:1:1. This paste was then applied to nickel foam and dried to a density of 100 kg / cm². 2 Under pressure, a positive electrode (nickel positive electrode) (nickel electrode A2) is formed by pressing. A 10 μm thick layer of gel material B2 is then electrostatically sprayed onto it. A zinc electrode coated with both gel material B2 and gel material A2 is stacked opposite a nickel electrode coated with gel material B2, and subjected to a temperature of 95℃ and 100 kg / cm². 2 The battery cell is formed by hot pressing under pressure, and the composite gel electrolyte matrix layer has a thickness of 35μm.

[0065] The obtained battery cell was placed in a battery container, leaving a cavity between the upper part of the cell and the outer casing. Using a syringe, 6 mol / L KOH electrolyte was added to the cavity between the upper part of the cell and the outer casing through a sealing ring. After the cell absorbed the electrolyte, the syringe was removed, and the battery was aged at 60°C for 6 hours to obtain a zinc-nickel battery (composite gel battery A2) based on octadecyl dimethyl betaine modified composite gel.

[0066] Tests showed that this zinc-nickel battery had a zinc electrode specific capacity exceeding 300 mAh / g, achieved a charge-discharge efficiency of 90%, and maintained a capacity of 200 mAh / g after 500 cycles. In contrast, commercially available zinc-nickel batteries using 6 mol / L KOH electrolyte failed after only 180 cycles. Figure 2 As shown.

[0067] Example 3: Zinc-nickel battery based on phosphate-betaine modified composite gel

[0068] 5g of polyacrylic acid powder with a molecular weight of 50,000 was dissolved in 100mL of deionized water at 95℃ and dispersed under ultrasonic vibration at a frequency of 130kHz for 30 minutes to obtain a polyacrylic acid solution (solution A3). 10g of polyvinyl alcohol powder with a molecular weight of 50,000 was dissolved in 100mL of deionized water at 95℃ and dispersed under ultrasonic vibration at a frequency of 130kHz for 30 minutes to obtain a polyvinyl alcohol solution (solution B3). Solution B3 was added dropwise to solution A3; the mixture was stirred at 1000rpm for 2.0h to obtain a high molecular weight PAA-PVA gel solution (gel solution A3). Gel solution A3 was spray-dried to obtain PAA-PVA gel powder material (gel material A3).

[0069] 5g of betaine phosphate produced by Shanghai Yuanye Biotechnology Co., Ltd. was dissolved in 100mL of deionized water at 95℃ and dispersed under ultrasonic vibration at 130kHz for 30 minutes to obtain a surfactant solution (surfactant solution C3). Solutions A3 and B3 were simultaneously added dropwise to the above surfactant solution C3, and the reaction was stirred at 100℃ for 2.0h to obtain a betaine phosphate modified PAA-PVA gel solution (gel solution B3). After spray drying, a betaine phosphate modified PAA-PVA powder gel material (gel material B3) was obtained.

[0070] Using gel material B3 as a binder, zinc oxide, acetylene black, and the binder were mixed in a mass ratio of 7:2:1, with deionized water added, and then mechanically ground to form a paste. The paste was applied to the upper and lower surfaces of the galvanized copper mesh and dried at 100 kg / cm². 2 The zinc electrode (zinc electrode A3) is obtained by pressing under pressure. A 15μm layer of gel material B3 is electrostatically sprayed on, followed by a 30μm layer of gel material A3, to obtain a zinc electrode coated with a hydrogel matrix material.

[0071] Nickel hydroxide, commercially available nickel carbonyl powder, and gel material B3 were mixed in a mass ratio of 8:1:1, ground with deionized water to form a paste, and then applied to nickel foam. After drying, the paste was heated to 100 kg / cm³. 2 The nickel electrode (nickel electrode A3) was formed by pressing under pressure, and then electrostatically sprayed with a 15μm thick gel material B3. The zinc electrode and nickel electrode coated with the gel matrix were then stacked facing each other and subjected to 100℃ and 100kg / cm² pressure. 2 The battery cell is formed by hot pressing under pressure, and the composite gel electrolyte matrix layer has a thickness of 50μm.

[0072] The obtained battery cell was placed inside a battery container, leaving a cavity between the upper part of the cell and the outer casing. Using a syringe, 6 mol / L KOH electrolyte was added to the cavity between the upper part of the cell and the outer casing through a sealing ring. After the cell absorbed the electrolyte, the syringe was removed, and the battery underwent an aging treatment at 60°C for 9 hours. This resulted in a zinc-nickel battery (composite gel battery A3) based on a phosphate betaine surfactant-modified composite gel. Figure 3 Before and after being placed at 50°C for 30 days, the discharge curves of the composite gel battery of the present invention and the commercially available zinc-nickel battery using 6 mol / L KOH electrolyte were compared. The capacity retention rate of the composite gel battery was higher than that of the commercially available zinc-nickel battery, indicating that the composite gel modified with phosphate betaine surfactant has a good effect on suppressing self-discharge.

[0073] Example 4: Zinc-nickel battery based on octadecylpropylhydroxysulfonate-modified composite gel

[0074] 10g of polyacrylic acid powder with a molecular weight of 100,000 was dissolved in 100mL of deionized water at 100℃ and dispersed under ultrasonic vibration at a frequency of 25kHz for 30 minutes to obtain a polyacrylic acid solution (solution A4). 10g of polyvinyl alcohol powder with a molecular weight of 100,000 was dissolved in 100mL of deionized water at 100℃ and dispersed under ultrasonic vibration at a frequency of 25kHz for 30 minutes to obtain a polyvinyl alcohol solution (solution B4). Solution B4 was added dropwise to solution A4; the mixture was stirred at 1000rpm for 2.0h to obtain a high molecular weight PAA-PVA gel solution (gel solution A4). Gel solution A4 was spray-dried to obtain PAA-PVA gel powder material (gel material A4).

[0075] 10 g of octadecylpropylhydroxysulfonate betaine (from Ruijie Chemical) was dissolved in 100 mL of deionized water at 100 °C. After dispersion at an ultrasonic vibration frequency of 130 kHz for 30 minutes, a surfactant solution (surfactant solution C4) was obtained. Solutions A4 and B4 were simultaneously added dropwise to the above surfactant solution C4. After stirring and reacting at 95 °C for 2.0 h, a phosphate betaine-modified PAA-PVA gel solution (gel solution B4) was obtained. After spray drying, octadecylpropylhydroxysulfonate betaine-modified PAA-PVA powder gel material (gel material B4) was obtained.

[0076] Using gel material B4 as a binder, zinc oxide, acetylene black, and the binder were mixed in a mass ratio of 7:2:1, with distilled water added, and then mechanically ground to form a paste. The paste was applied to the upper and lower surfaces of a galvanized copper mesh and dried at 100 kg / cm². 2 The zinc electrode (zinc electrode A4) is obtained by pressing under pressure. Then, gel material B4 and gel material A4 are sequentially sprayed onto one side of the zinc electrode using electrostatic spraying; the thickness of gel material B4 is 20 μm, and the thickness of gel material A4 is 40 μm.

[0077] Nickel hydroxide, commercially available nickel carbonyl powder, and gelling material B4 were mixed in a mass ratio of 8:1:1, ground with deionized water to form a paste, and then applied to nickel foam. After drying, the paste was heated to 100 kg / cm³. 2 The nickel electrode (nickel electrode A4) was formed by pressing under pressure, and a 20 μm thick gel material B4 was electrostatically sprayed onto it. The zinc electrode and nickel electrode coated with the gel matrix were then stacked facing each other and subjected to a temperature of 95℃ and a pressure of 100 kg / cm². 2 The battery cell is formed by hot pressing under pressure, and the composite gel electrolyte matrix layer has a thickness of 70μm.

[0078] The obtained battery cell was placed inside a battery container, leaving a cavity between the upper part of the cell and the outer casing. Using a syringe, 9 mol / L KOH electrolyte was added to the cavity between the upper part of the cell and the outer casing through a sealing ring. After the cell absorbed the electrolyte, the syringe was removed, and the battery underwent an aging treatment at 60°C for 12 hours. This resulted in a zinc-nickel battery (composite gel battery A4) based on octadecylpropylhydroxysulfonate modified composite gel. Figure 4 The image shows a comparison of dendrite growth in a commercially available zinc-nickel battery and the composite gel battery of this invention after 200 charge-discharge cycles. The left image shows the dendrite growth of the zinc electrode in the commercially available zinc-nickel battery, while the right image shows the dendrite growth of the zinc electrode after the composite gel electrolyte of this invention was modified with octadecylpropylhydroxysulfonate. Almost no zinc dendrite development is visible, fully demonstrating that the composite gel electrolyte has a good inhibitory effect on dendrite development.

[0079] Example 5: Zinc-nickel battery based on dodecylbenzenesulfonium ammonium modified composite gel

[0080] 2g of polyacrylic acid powder with a molecular weight of 50,000 was dissolved in 100mL of deionized water at 100℃ and dispersed under ultrasonic vibration at a frequency of 25kHz for 30 minutes to obtain a polyacrylic acid solution (solution A5). 10g of polyvinyl alcohol powder with a molecular weight of 100,000 was dissolved in 100mL of deionized water at 100℃ and dispersed under ultrasonic vibration at a frequency of 25kHz for 30 minutes to obtain a polyvinyl alcohol solution (solution B5). Solution B5 was added dropwise to solution A5; the mixture was stirred at 1000rpm for 2.0h to obtain a high molecular weight PAA-PVA gel solution (gel solution A5). Gel solution A5 was spray-dried to obtain PAA-PVA gel powder material (gel material A5).

[0081] 3g of dodecylbenzenesulfonammonium (Hubei Guangao Biotechnology Co., Ltd.) was dissolved in 100mL of deionized water at 100℃ and dispersed under ultrasonic vibration at 130kHz for 30 minutes to obtain a surfactant solution (surfactant solution C5). Solutions A5 and B5 were simultaneously added dropwise to the above surfactant solution C5, and the reaction was stirred at 95℃ for 2.0h to obtain a dodecylbenzenesulfonammonium-modified PAA-PVA gel solution (gel solution B5). After spray drying, a dodecylbenzenesulfonammonium-modified PAA-PVA powder gel material (gel material B5) was obtained.

[0082] Using gel material B5 as a binder, zinc oxide, acetylene black, and the binder were mixed in a mass ratio of 7:2:1, with distilled water added, and then mechanically ground to form a paste. The paste was applied to the upper and lower surfaces of a galvanized copper mesh and dried at 100 kg / cm². 2The zinc electrode (zinc electrode A5) is obtained by pressing under pressure. Then, gel material B5 and gel material A5 are sequentially sprayed onto one side of the zinc electrode using electrostatic spraying; the thickness of gel material B5 is 20 μm, and the thickness of gel material A5 is 60 μm.

[0083] Nickel hydroxide, commercially available nickel carbonyl powder, and gel material B5 were mixed in a mass ratio of 8:1:1, ground with deionized water to form a paste, and then applied to nickel foam. After drying, the paste was heated to 100 kg / cm³. 2 The nickel electrode (nickel electrode A5) was formed by pressing under pressure, and a 20 μm thick gel material B5 was electrostatically sprayed onto it. The zinc electrode and nickel electrode coated with the gel matrix were then stacked facing each other and subjected to a temperature of 95℃ and a pressure of 100 kg / cm². 2 Under pressure, it is hot-pressed to form a battery cell (battery cell A5), with a composite gel electrolyte matrix layer thickness of 80μm.

[0084] The obtained battery cell was placed inside a battery container, leaving a cavity between the upper part of the battery cell and the outer casing. Using a syringe, 12 mol / L KOH electrolyte was added to the cavity between the upper part of the battery cell and the outer casing through a sealing ring. After the battery cell had absorbed the electrolyte, the syringe was removed, and the battery was aged at 60°C for 12 hours. This resulted in a zinc-nickel battery (composite gel battery A5) based on dodecylbenzenesulfonium ammonium modified composite gel.

[0085] Comparative Example: Single-component gel zinc-nickel battery

[0086] Follow the same steps (e.g.) Figure 5 As shown), PAA-PVA gel zinc-nickel batteries can be obtained using a copolymer of polyacrylic acid and polyvinyl alcohol. For example, using the corresponding PAA-PVA gel material A5 as a binder, zinc powder, acetylene black, and binder are mixed in a mass ratio of 7:2:1, with an appropriate amount of deionized water added, and then mechanically ground to form a paste. The paste is applied to the upper and lower surfaces of a galvanized copper mesh and dried at 100 kg / cm². 2 The zinc electrode (zinc electrode A5-1) is obtained by pressing under pressure. After spraying gel material A5 onto one side of the zinc electrode, a modified zinc electrode (zinc electrode B5-1) with gel material on one side is obtained; wherein, the thickness of the gel material layer is 50 μm.

[0087] Similarly, nickel hydroxide, commercially available nickel carbonyl powder, and gel material A5 were taken in a mass ratio of 8:1:1, ground with deionized water to form a paste, and then coated onto the nickel foam; after drying, it was heated at 100 kg / cm². 2 Under pressure, a nickel electrode (nickel electrode A5-1) was obtained by pressing and molding. Similarly, a 50 μm thick layer of gel material A5 was electrostatically sprayed onto it to obtain a gel-modified nickel electrode (B5-1). Zinc and nickel electrodes coated with the gel matrix were stacked facing each other and subjected to a temperature of 95℃ and 100 kg / cm².2 Under pressure, the battery cell (cell A5-1) is formed by hot pressing. The thickness of the PAA-PVA gel electrolyte matrix layer is 80μm.

[0088] Comparative testing and results analysis

[0089] The composite gel battery cell (cell A5) based on dodecylbenzenesulfonium ammonium modification obtained in Example 5 and the single-component gel zinc-nickel battery (cell A5-1) obtained in the comparative example were placed in their respective battery containers, leaving a cavity between the upper part of the cell and the outer shell. Using a syringe, 12 mol / L KOH electrolyte was added to the cavity between the upper part of the cell and the outer shell through a sealing ring. After the cell absorbed the electrolyte, the syringe was removed, and the cells were aged at 60°C for 12 hours to obtain a zinc-nickel battery (composite gel battery A5) based on dodecylbenzenesulfonium ammonium modified composite gel and a PAA-PVA single-component gel zinc-nickel battery (single-component gel battery A5-1), respectively.

[0090] Figure 6 For zinc-nickel batteries using dodecylbenzenesulfonium ammonium modified composite gel and single-component PAA-PVA gel at 300 mA / cm 2 Impedance comparison under current density discharge. Results show that at 300 mA / cm²... 2 During discharge, the impedance of the zinc-nickel battery using the composite gel modified with dodecylbenzenesulfonium ammonium was significantly lower than that of the zinc-nickel battery using the single-component PAA-PVA gel. This indicates that the use of composite gel significantly enhances the hydrogen exhaust effect, prevents the separation of the gel from the electrode, and effectively reduces the electrode impedance.

[0091] Finally, the above-disclosed embodiments are merely specific examples of the present invention. The preparation process of the composite gel zinc-nickel battery of the present invention is summarized in... Figure 5 All modifications that can be directly derived or conceived by those skilled in the art from the content disclosed in this invention should be considered within the scope of protection of this invention.

Claims

1. A method for preparing a gel material for suppressing zinc dendrites, characterized in that, Includes the following steps: (1) Take 1-10 g of polyacrylic acid (PAA) powder with a molecular weight of 5,000-100,000, dissolve it in 100 mL of deionized water at 80-100℃, and disperse it by ultrasonic vibration for 30 minutes to obtain a PAA solution; take 1-10 g of polyvinyl alcohol (PVA) powder with a molecular weight of 5,000-100,000, dissolve it in 100 mL of deionized water at 80-100℃, and disperse it by ultrasonic vibration for 30 minutes to obtain a PVA solution; (2) The PVA solution is added dropwise to the PAA solution, and after stirring and polymerization for 0.5 to 2.0 h, a gel solution is obtained; after spray drying, PAA-PVA copolymer powder is obtained, referred to as gel powder; (3) Take 1-10 g of amphoteric surfactant, dissolve it in 100 mL of deionized water at 80-100℃, and disperse it by ultrasonic vibration for 30 minutes to obtain a surfactant solution; (4) Prepare PAA solution and PVA solution again according to the method in step (1), and add them dropwise to the amphoteric surfactant solution. The mass ratio of amphoteric surfactant, PAA and PVA is 1:(1~5):(1~2). After stirring and reacting at 80~100℃ for 0.5~2.0 h, an amphoteric surfactant modified gel solution is obtained. After spray drying, amphoteric surfactant modified PAA-PVA is obtained, which is the gel material used to suppress zinc dendrites.

2. The method according to claim 1, characterized in that, The ultrasonic vibration frequency range in each step is 25–130 kHz.

3. The method according to claim 1, characterized in that, The stirring speed in each step is 50–1000 rpm.

4. The method according to claim 1, characterized in that, The amphoteric surfactant molecule has both acidic and basic groups; wherein the acidic group is a carboxyl group, a sulfonic acid group, or a phosphate group, and the basic group is an amino group or a quaternary ammonium group.

5. A method for further preparing a zinc electrode using the gel material prepared by the method of claim 1, characterized in that, Includes the following steps: (1) Using the gel material as a binder, zinc oxide, acetylene black and binder are taken in a mass ratio of 7:2:1, and an appropriate amount of deionized water is added. After mechanical grinding and mixing, a paste is formed. The paste is applied to the upper and lower surfaces of the galvanized copper mesh and dried at 100 kg / cm². 2 Zinc electrodes are obtained by pressing them under pressure to form a mold. (2) The gel material and gel powder are sequentially sprayed on one side of the zinc electrode by electrostatic spraying to form a double-layer spraying structure, thereby obtaining a zinc electrode coated with composite gel material.

6. The method according to claim 5, characterized in that, In the double-layer sprayed structure of the zinc electrode, the thickness of the gel material layer is 2-20 μm, and the thickness of the gel powder layer is 6-60 μm.

7. A method for further preparing a composite gel zinc-nickel battery capable of suppressing zinc dendrites using the zinc electrode prepared by the method of claim 5, characterized in that, Includes the following steps: (1) Take nickel hydroxide, nickel carbonyl powder and gel material in a mass ratio of 8:1:1, add an appropriate amount of deionized water and grind to form a paste; then apply it to the nickel foam, and after drying, 100 kg / cm 2 Nickel electrodes are obtained by pressing them under pressure to form a nickel electrode. (2) A gel material with a thickness of 2 to 20 μm is electrostatically sprayed onto one side of the nickel electrode to obtain a nickel electrode coated with gel material; (3) Stack the coatings of the zinc electrode and the nickel electrode facing each other, and then heat them at 90-100℃ and 100 kg / cm². 2 Under pressure, hot pressing is used to form composite gel material battery cells; (4) Place the composite gel material cell in the battery container and add 3-9 mol / L KOH electrolyte; let it stand at 60°C for 3-12 hours for aging treatment to obtain zinc-nickel battery based on modified composite gel.

8. A zinc-nickel battery prepared according to the method of claim 7, characterized in that, The zinc-nickel battery includes a battery container consisting of a negative electrode shell and a positive electrode shell, with the positive and negative electrode shells insulated and isolated from each other by a sealing ring. The composite gel material battery cell with a sandwich structure inside the battery container is formed by hot pressing zinc and nickel electrodes stacked facing each other with their respective coatings. The coating on the zinc electrode includes gel material and gel powder, and the coating on the nickel electrode includes gel material. The gel material is PAA-PVA copolymer powder modified with amphoteric surfactant, and the gel powder is unmodified PAA-PVA copolymer powder. The multilayer coating materials together form a composite gel matrix inside the composite gel material battery cell. A cavity is left between the upper part of the battery cell and the outer shell. Electrolyte is injected into the cavity through a sealing ring using a syringe. After the composite gel matrix inside the battery cell absorbs the electrolyte, it forms a composite gel electrolyte.

9. The zinc-nickel battery according to claim 8, characterized in that, The electrolyte is a 3-12 mol / L KOH solution.

10. The zinc-nickel battery according to claim 8, characterized in that, The thickness of the composite gel matrix inside the composite gel material battery cell is 8–80 μm.

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