Zinc metal negative electrode, preparation method, aqueous zinc-based battery and zinc metal soft package battery

Abstract

The invention provides a zinc metal negative electrode and a preparation method thereof. The zinc metal negative electrode comprises a zinc substrate and a metal halide artificial interface layer formed on at least part of the surface of the zinc substrate, the metal halide artificial interface layer is formed by a metal halide perovskite material, and according to the zinc metal negative electrode, by screening and optimizing the type and dosage of metal halide, a compact and firm protection layer is constructed on zinc metal in situ, the limitation of a single organic or inorganic coating is overcome, and the stability of the zinc metal negative electrode is effectively improved. The multifunctional hybrid coating not only has rich zinc-loving sites, high conductivity and low charge transfer resistance, but also has relatively low nucleation potential barrier and uniform electric field distribution, induces Zn < 2 + > to be uniformly deposited, and synergistically solves the problems of dendritic crystal growth, hydrogen evolution reaction, corrosion and the like of a zinc negative electrode. In addition, the invention also provides an aqueous zinc-based battery comprising the zinc metal negative electrode and a zinc metal soft package battery.

Description

Technical Field

[0001] This application relates to the field of fuel cell technology, and in particular to a zinc metal anode, a preparation method, an aqueous zinc-based battery, and a zinc metal pouch battery. Background Technology

[0002] With the rapid development of the electric transportation market and the emergence of various electronic devices, especially in applications such as electric vehicles and large-scale energy storage, the urgent need for energy storage technology has been further intensified. Therefore, developing low-cost, high-safety, and resource-rich electrochemical energy storage systems is an important goal in the development of energy storage technology. Among many novel energy storage technologies, aqueous zinc-ion batteries benefit from their intrinsically high safety and low redox potential (…). 0.762 V vs. SHE), high theoretical capacity (5855 mAh cm⁻¹) 3 and 820 mAh g –1 Zinc is a promising new energy storage technology with advantages such as abundant resources and environmental friendliness, and it has significant application prospects in the field of distributed energy storage. However, zinc metal has high electrochemical activity, and the stripping / deposition process of zinc ions in aqueous zinc-ion batteries is affected by a combination of thermodynamics and kinetics. Active water at the interface between the zinc metal anode and the aqueous electrolyte can cause side reactions such as dendrite growth, corrosion, and hydrogen evolution in the zinc anode, severely affecting the coulombic efficiency and cycle life of aqueous zinc-ion batteries. Especially in large-capacity pouch batteries, the zinc foil, which serves as both the anode and current collector, may experience Zn degradation during cycling. 2+ Uneven deposition leads to severe pulverization and fracture; at the tab, the localized concentrated electric field effect causes Zn to... 2+ Dendrite aggregation leads to short circuits in batteries, severely hindering the development and large-scale application of aqueous zinc-based batteries. Effectively addressing the stability issue of the zinc metal interface is crucial for improving its electrochemical performance and realizing its application value. To enhance the stability of zinc anodes, various strategies have been proposed, including zinc metal anode structural design, interface layer modification, electrolyte composition control, and separator optimization. Among these, the strategy of constructing artificial interface layers has attracted widespread attention due to its high cost-effectiveness, diverse preparation methods, ease of processing, and large-scale production capability. This technology can regulate zinc ion deposition behavior, achieving uniform nucleation and a flat zinc deposition layer, which is beneficial for increasing the hydrogen evolution potential of metallic zinc and inhibiting corrosion reactions. Furthermore, artificial interface layers can directly prevent direct contact between the electrolyte and the zinc anode, or reduce the number of water molecules reaching the zinc anode surface through desolvation, mitigating side reactions and improving the reversibility and cycle life of the zinc anode.

[0003] Currently reported materials for constructing zinc anode surface coatings mainly fall into four categories: carbon-based materials, metal-based materials, inorganic non-metallic materials, and polymer materials. Carbon-based materials offer advantages such as abundant resources, low cost, large specific surface area, and environmental friendliness, providing ample sites for zinc nucleation. However, they suffer from low strength, are prone to fracture, and are susceptible to problems such as "dead zinc" formation within the material, resulting in a limited lifespan. Metallic materials exhibit higher strength, better conductivity, and a stronger affinity for zinc, which can increase the nucleation sites for zinc. 2+ Nucleation sites exist, but galvanic corrosion problems exist between the material and zinc metal. Inorganic non-metallic materials have advantages such as corrosion resistance, long-lasting performance, and environmental friendliness. Furthermore, as a non-conductive protective layer, they do not suffer from problems caused by uneven electric field strength. However, their dense interface layer can lead to Zn... 2+ The migration rate decreases. The polymer coating offers good protection and abundant polar groups, effectively regulating zinc nucleation sites and suppressing side reactions of active water at the zinc anode. However, it lacks sufficient Zn. 2+ The slow transport channels and reaction kinetics negatively impact the rate performance and cycle stability of zinc-ion batteries. Furthermore, the stability and rate performance of zinc-ion batteries are limited by the inhomogeneity between the coating material and the zinc metal anode, which can lead to problems such as insufficient coating adhesion and peeling during cycling. Summary of the Invention

[0004] In view of this, the present invention provides a zinc metal anode, a preparation method, an aqueous zinc-based battery, and a zinc metal pouch battery to improve the stability of aqueous zinc-based batteries.

[0005] To solve the above problems, this application adopts the following technical solution: One objective of this application is to provide a zinc metal anode, comprising a zinc substrate and a metal halide artificial interface layer formed on at least a portion of the surface of the zinc substrate; the metal halide artificial interface layer is formed of a metal halide perovskite material.

[0006] In some embodiments, the metal halide perovskite material has an ABX3 structure, wherein the A-site is an organic group with a zinc-loving site, the B-site is a metal cation, and the X-site is a halide anion.

[0007] In some embodiments, the A-position organic group is one or more selected from trimethylsulfonium iodide, trimethylsulfonium bromide, 4,4-difluoropiperidine, 1,8-octanediamine, dimethylamine hydrochloride, diethylenetriamine, and N,N'-dimethylethylenediamine; and the B-position metal cation is Zn²⁺. + Sn² + Bi³ + One or more of the following; the X-position halide anion is Cl. - ,Br - I -One or more of them.

[0008] In some embodiments, the zinc substrate is zinc foil or zinc powder.

[0009] The second objective of this application is to provide a method for preparing the zinc metal negative electrode, wherein when the zinc substrate is zinc foil, the method includes the following steps: The metal halide perovskite material was dissolved in an organic solvent and stirred until a clear solution was obtained. The clarified solution is coated onto the surface of zinc foil; The solvent evaporates at room temperature, thus forming an artificial interface layer of metal halide on the zinc foil surface.

[0010] In some embodiments, the organic solvent is one or more of N-methylpyrrolidone or N,N-dimethylformamide; the concentration of the clarified solution is 30 mg / ml. - ¹ ~ 200 mg ml - ¹; the thickness of the doctor blade coating is 50~200 μm; the thickness of the zinc foil is 10~200 μm.

[0011] The third objective of this application is to provide a method for preparing the zinc metal anode, wherein when the zinc substrate is zinc powder, the method includes the following steps: Metal halide perovskite material is mixed with zinc powder and mechanically ball-milled to generate modified zinc powder with a metal halide artificial interface layer on the surface through in-situ reaction. The modified zinc powder, conductive agent, and binder are mixed and pressed onto the current collector to prepare an electrode.

[0012] In some embodiments, the mass ratio of the metal halide perovskite material to zinc powder is 1:1 to 1:10; the particle size of the zinc powder ranges from 0 to 150 μm; the rotation speed of the mechanical ball mill is 100 to 1000 r / min, and the ball milling time is 30 min to 5 h.

[0013] In some embodiments, the conductive agent is acetylene black, the binder is polytetrafluoroethylene (PTFE), the mass ratio of modified zinc powder, acetylene black, and PTFE is 8:1:1 or 7:2:1, and the current collector is an ultra-thin titanium mesh or a tin-plated copper mesh.

[0014] In some embodiments, the metal halide perovskite material has an ABX3 structure, wherein the A-site is an organic group with a zinc-loving site, the B-site is a metal cation, and the X-site is a halide anion.

[0015] In some embodiments, the A-position organic group is one or more selected from trimethylsulfonium iodide, trimethylsulfonium bromide, 4,4-difluoropiperidine, 1,8-octanediamine, dimethylamine hydrochloride, diethylenetriamine, and N,N'-dimethylethylenediamine; and the B-position metal cation is Zn²⁺. + Sn² + Bi³ + One or more of the following; the X-position halide anion is Cl. - ,Br - I - One or more of them.

[0016] The fourth objective of this application is to provide an aqueous zinc-based battery, comprising a positive electrode, a negative electrode, a separator, and an electrolyte, wherein the negative electrode is the zinc metal negative electrode described herein, or a zinc metal negative electrode prepared by the method described herein.

[0017] In some embodiments, the positive electrode material is manganese dioxide, vanadium dioxide, vanadium pentoxide, ammonium vanadate, organic covalent organic framework material, elemental bromine, or elemental iodine; the electrolyte is zinc sulfate solution, zinc trifluoromethanesulfonate solution, zinc bis(trifluoromethanesulfonyl)imide solution, or zinc chloride solution; and the separator is a glass fiber type, cellulose type, polyacrylonitrile type, Nafion type, or graphene oxide type separator.

[0018] The fifth objective of this application is to provide a zinc metal pouch battery, wherein the pouch battery comprises the aforementioned aqueous zinc-based battery.

[0019] The present application adopts the above technical solution, and its beneficial effects are as follows: The zinc metal anode provided in this application includes a zinc substrate and a metal halide artificial interface layer formed on at least a portion of the surface of the zinc substrate. The metal halide artificial interface layer is formed from metal halide perovskite material. This application, by screening and optimizing the type and amount of metal halides, constructs a dense and robust protective layer in situ on the zinc metal, overcoming the limitations of single organic or inorganic coatings and effectively improving the stability of the zinc metal anode. This multifunctional hybrid coating not only possesses abundant zinc-affinity sites, high conductivity, and low charge transfer resistance, but also has a low nucleation barrier and a uniform electric field distribution, inducing Zn... 2+ Uniform deposition synergistically addresses issues such as dendrite growth, hydrogen evolution reaction, and corrosion in zinc anodes; furthermore, the designed metal halide artificial interface layer utilizes organic materials rich in zinc-loving functional groups, resulting in a Zn interface... 2+ Uniform flux is achieved to synergistically improve the reversibility and stability of the battery; in addition, different metal halide interface layers can regulate halogen-induced Zn. 2+ Uniform diffusion optimizes zinc deposition behavior, achieving high stability in zinc metal anodes.

[0020] The zinc metal anode preparation method provided in this application has advantages such as low cost, good mechanical properties, simple preparation, good reproducibility and large-scale preparation. In addition, it fully considers the compatibility of material properties and construction technology, effectively improves the stability of zinc anode and ensures the universality of the interface layer.

[0021] The zinc metal anode provided in this application can be applied to aqueous zinc-based batteries, achieving high reversibility and ultra-long cycle stability. This indicates that the metal halide artificial interface layer can not only effectively suppress interfacial side reactions and extend cycle life, but also promote the rapid transport and uniform deposition of zinc ions. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments of this application or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a flowchart illustrating the steps of a method for preparing a zinc metal anode provided in an embodiment of this application.

[0024] Figure 2 A flowchart illustrating the steps of a method for preparing a zinc metal negative electrode according to another embodiment of this application.

[0025] Figure 3 SEM image of zinc foil modified with zinc-based metal halide artificial interface layer provided in Example 1 of this application; Figure 4 The SEM and XRD patterns of zinc powder modified with bismuth-based metal halide artificial interface layer provided in Example 2 of this application; Figure 5 The zinc-zinc symmetric cells assembled from the bismuth-based metal halide artificial interface layer-modified zinc foil and the bare zinc foil negative electrode, respectively, according to Example 4 of this application, operate at a current density of 2 mA cm⁻¹. –2 The deposition capacity is 2 mAh cm⁻¹ –2 Cyclic performance graph under the given conditions; Figure 6 The zinc-zinc symmetric cells assembled from zinc foil modified with a zinc-based metal halide artificial interface layer and bare zinc foil negative electrodes, as provided in Example 4 of this application, operate at a current density of 5 mA cm⁻¹. –2 The deposition capacity is 5 mAh cm⁻¹ –2 Cyclic performance graph under the given conditions; Figure 7The charge-discharge curves are for the zinc-ion full cell assembled with a zinc foil negative electrode modified with a bismuth-based metal halide artificial interface layer as provided in Example 5 of this application. Detailed Implementation

[0026] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. In the description of this application, it should be understood that the terms "upper", "lower", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified. To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments.

[0027] The zinc metal anode provided in this application includes: a zinc substrate and a metal halide artificial interface layer formed on at least a portion of the surface of the zinc substrate; the metal halide artificial interface layer is formed of a metal halide perovskite material.

[0028] In this embodiment, zinc provides the battery capacity. Both zinc foil and zinc powder, as negative electrode materials, possess fundamental advantages such as high theoretical capacity, low potential, and high hydrogen evolution overpotential. The presence of the interface layer primarily acts as a physical barrier. It directly covers the zinc surface, preventing direct contact between the reactive zinc metal and the liquid aqueous electrolyte (containing a large number of water molecules and corrosive anions). This is the fundamental means to solve the problems of hydrogen evolution reaction and chemical corrosion at the zinc negative electrode.

[0029] It is understood that "at least part of the surface" encompasses both complete and selective coating. In most preferred solutions (such as complete coating), this means providing all-around, comprehensive protection for the entire zinc surface exposed to the electrolyte, ensuring that no exposed active sites trigger side reactions or dendrite growth.

[0030] Furthermore, the metal halide artificial interface layer is formed of a metal halide perovskite material. Metal halide materials themselves, especially those with a perovskite structure, typically possess high ionic conductivity. This means that Zn²⁺… + It can quickly penetrate this interface layer for efficient insertion / extraction or migration without significantly increasing the battery's internal resistance. This is fundamentally different from many polymer coatings that are electronically insulating or have low ionic conductivity, ensuring the battery's rate performance.

[0031] In some embodiments, the metal halide perovskite material has an ABX3 structure, wherein the A-site is an organic group with a zinc-loving site, the B-site is a metal cation, and the X-site is a halide anion.

[0032] In some embodiments, the A-position organic group is one or more selected from trimethylsulfonium iodide, trimethylsulfonium bromide, 4,4-difluoropiperidine, 1,8-octanediamine, dimethylamine hydrochloride, diethylenetriamine, and N,N'-dimethylethylenediamine; and the B-position metal cation is Zn²⁺. + Sn² + Bi³ + One or more of the following; the X-position halide anion is Cl. - ,Br - I - One or more of them.

[0033] It is understandable that the A-site is typically an organic cation, for example, the organic group at the A-site is one or more of trimethylsulfonium iodide, trimethylsulfonium bromide, 4,4-difluoropiperidine, 1,8-octanediamine, dimethylamine hydrochloride, diethylenetriamine, and N,N'-dimethylethylenediamine (these organic groups are rich in zinc-loving sites such as S and N atoms). When the interface layer comes into contact with the electrolyte, these zinc-loving sites can effectively adsorb Zn²⁺. + This allows it to be evenly distributed on the surface of the interface layer, thereby homogenizing the interfacial ion flux. This is the induction of Zn²⁺. + Uniform deposition is key to avoiding dendrite growth.

[0034] The BX inorganic framework forms the main channel for ion migration. The selection of B-site ions (such as Bi³⁺) is crucial. + Sn² + (etc.) can modulate the band structure of the interface layer and its affinity for zinc, and may even induce heterogeneous nucleation with low nucleation barriers. X-position halogens (Cl...) - , Br - , I - The coordination environment and species of Zn² can be precisely controlled. + The diffusion path and migration rate in the interface layer are optimized to improve the final zinc deposition morphology.

[0035] This synergistic effect, where "organic A-sites are responsible for surface adsorption and guidance, while the inorganic BX framework is responsible for rapid bulk transport and mechanical support," is something that single-component materials (such as pure polymers or pure inorganic salts) cannot achieve. Together, they contribute to improvements in a series of key electrochemical behaviors, including low nucleation barriers, uniform deposition, and rapid migration kinetics.

[0036] It should be noted that the types and amounts of organic compounds or halogen elements can be randomly combined. For example, zinc metal modified with a metal halide interface layer designed and synthesized using one or more organic groups or halogen elements falls within the scope of protection of this patent. Halide interface layers prepared by adding one or more metal halide perovskite materials also fall within the scope of protection of this patent.

[0037] It is understood that by changing the organic compounds or halides of metal halides, such as organic compounds trimethylsulfonium bromide, 4,4-difluoropiperidine, 1,8-octanediamine, etc., and halides Cl–, Br–, I–, etc., the application of the technical solution of this invention to the field of other metal (aluminum, magnesium, etc.) batteries is within the scope of protection of this patent.

[0038] The zinc metal anode provided in this application, through the selection and optimization of the type and amount of metal halides, constructs a dense and robust protective layer in situ on zinc metal, overcoming the limitations of single organic or inorganic coatings and effectively improving the stability of the zinc metal anode. This multifunctional hybrid coating not only possesses abundant zinc-affinity sites, high conductivity, and low charge transfer resistance, but also exhibits a low nucleation barrier and a uniform electric field distribution, inducing Zn... 2+ Uniform deposition synergistically addresses issues such as dendrite growth, hydrogen evolution reaction, and corrosion in zinc anodes; furthermore, the designed metal halide artificial interface layer utilizes organic materials rich in zinc-loving functional groups, resulting in a Zn interface... 2+ Uniform flux is achieved to synergistically improve the reversibility and stability of the battery; in addition, different metal halide interface layers can regulate halogen-induced Zn. 2+ Uniform diffusion optimizes zinc deposition behavior, achieving high stability in zinc metal anodes.

[0039] Please see Figure 1 This application also provides a method for preparing the zinc metal anode, which, when the zinc substrate is zinc foil, includes the following steps: Step S11: Dissolve the metal halide perovskite material in an organic solvent and stir until a clear solution is obtained.

[0040] It is understandable that during solvent evaporation, the dissolved perovskite material itself will crystallize or rearrange, allowing it to directly and firmly adhere to the zinc foil surface, forming a dense film. Eliminating the need for an insulating polymer binder helps maintain the high ionic conductivity of the interface layer, while also simplifying the formulation and process.

[0041] Step S12: Coat the zinc foil surface with the clarified solution.

[0042] Specifically, the above solution is poured onto zinc foil and uniformly coated using a doctor blade. This step allows for precise control of the wet film thickness by adjusting the gap between the doctor blade and the zinc foil. Since the final dry film thickness of the interface layer is directly related to the wet film thickness, this provides the process with strong designability and repeatability. A suitable thickness (preferably 50-200 μm in the preceding steps) ensures complete substrate coverage without significantly increasing ion transport resistance due to excessive thickness. Step S13: Evaporate the solvent at room temperature, thus forming a metal halide artificial interface layer on the zinc foil surface.

[0043] Understandably, compared to methods requiring heat curing, UV curing, or vacuum drying, "room temperature natural evaporation" is the gentlest and most energy-efficient method. It avoids the decomposition or phase transition of metal halide materials that can be caused by high temperatures, preserving the original structure and function of the material. No additional energy input or complex equipment is required, further reducing production costs and technical barriers. The solvent evaporates naturally in a ventilated environment, making it simple to operate and ideal for continuous production.

[0044] Specifically, at room temperature, a certain amount of metal halide perovskite material is directly added to an organic solvent without the addition of an additional binder. The mixture is stirred at room temperature for 30 minutes until the solution becomes clear. This solution is then poured onto zinc foil and uniformly coated using a doctor blade. Finally, after the solvent has evaporated naturally at room temperature, a zinc foil negative electrode with an artificial metal halide protective layer is obtained. Examples of suitable metal halides include [(CH3)3S]2[ZnBr4] and DFPD3BiI6 (DFPD: 4,4-difluoropiperidine). Preferably, in the metal halide perovskite material ABX3, the A-site is an organic group with abundant zinc-loving sites, such as one or more of trimethylsulfonium iodide, trimethylsulfonium bromide, 4,4-difluoropiperidine, 1,8-octanediamine, dimethylamine hydrochloride, diethylenetriamine, N,N'-dimethylethylenediamine, etc.

[0045] Preferably, in the metal halide ABX3, the B-site is a metal cation Zn. 2+ Sn 2+ Bi 3+ One or more of them, where the halogen at the X-position is Cl. – ,Br – and I – One or more of them.

[0046] It is understood that the metal halide perovskite materials screened in this embodiment combine the advantages of organic components (A-site) and inorganic components (BX-site). Organic chains (such as trimethylsulfonium iodide, 4,4-difluoropiperidine, etc.) provide abundant zinc-loving sites, effectively guiding Zn²⁺. + Uniform distribution; while inorganic framework (Zn²) + Sn² + Bi³ + (etc.) endow the interface layer with high mechanical strength and structural stability. The synergistic effect of this hybrid structure compensates for the defects of a single organic layer being easily soluble in electrolyte or a single inorganic layer being brittle.

[0047] Metal cations in metal halides (such as Bi³⁺) + ) and Zn² + It exhibits a tendency for lattice matching or alloying, and can serve as a heterogeneous nucleation site, significantly reducing the nucleation overpotential of zinc and promoting uniform zinc deposition.

[0048] Preferably, the organic solvent is one or more of N-methylpyrrolidone (NMP), N,N-dimethylformamide (DMF), etc.

[0049] Preferably, a certain amount of the metal halide perovskite material is added to an organic solvent, and the solution concentration is 30 mg / ml. 1 ~ 200 mg ml 1 .

[0050] Preferably, the thickness of the blade coating is 1 ~ 200 μm.

[0051] Preferably, the zinc foil thickness is 10 ~ 200 μm.

[0052] Preferably, the zinc foil is cut to the required size for use.

[0053] The zinc metal anode provided in the above embodiments of this application directly constructs an interface layer on the zinc foil, which serves as both the anode and current collector, without requiring additional transfer steps. The entire process is carried out at room temperature and atmospheric conditions, representing a typical low-cost, high-efficiency solution. This method is perfectly compatible with industrially mature roll-to-roll coating processes. Large-scale continuous production can be achieved by unrolling the zinc foil roll, coating, drying (room temperature evaporation can be considered extremely low-energy drying), and rewinding. The binder-free design ensures high purity of the interface layer, maximizing the intrinsic advantage of the high ionic conductivity of metal halide perovskite materials. The resulting dense interface layer covers the active sites on the zinc foil surface, redistributing the electric field and Zn² at the interface. +The increased ion flux avoids the tip effect, thus fundamentally inhibiting the vertical growth of zinc dendrites. Furthermore, the metal halide artificial interface layer acts as a physical barrier, effectively blocking direct contact between zinc metal and the aqueous electrolyte. On one hand, this avoids the side reaction (hydrogen evolution) between zinc and water, improving coulombic efficiency; on the other hand, it inhibits the chemical corrosion of the zinc anode by the electrolyte, significantly extending the cycle life of the zinc anode.

[0054] Please see Figure 2 This is a flowchart of the preparation method for the zinc metal anode provided in this embodiment. When the zinc substrate is zinc powder, the method includes the following steps: Step S21: Mix metal halide perovskite material with zinc powder and mechanically ball-mill to generate modified zinc powder with a metal halide artificial interface layer on the surface through in-situ reaction.

[0055] It is understandable that mechanical energy drives the in-situ construction of a uniformly composed and firmly bonded artificial interface layer on the zinc powder surface. The high-energy collisions provided by mechanical ball milling not only break down, refine, and uniformly adhere the metal halide perovskite material to the zinc powder surface, but may also drive slight in-situ chemical reactions or interface fusion between the two (such as the reaction between bismuth-based halides and zinc mentioned in the material description). This results in a strong bond between the generated interface layer and the zinc powder substrate, rather than simple physical adsorption, making it difficult to detach. For micron-sized zinc powder particles, traditional liquid-phase coating methods (such as dip-coating) easily lead to particle agglomeration or uneven coating. Mechanical ball milling is an efficient and reliable powder surface uniform modification technology that ensures a relatively complete and uniform protective layer is formed on the surface of each zinc powder particle. Furthermore, the ball milling process itself can change the morphology and particle size of the zinc powder, which helps optimize the electrode packing density and pore structure.

[0056] Step S22: Mix the modified zinc powder, conductive agent and binder, and press them onto the current collector to prepare an electrode.

[0057] It is understandable that functionalized active powder materials are assembled into composite electrodes with practical structures and good mechanical strength through mature electrode fabrication processes. Modified zinc powder serves as the active host, providing capacity. Added conductive agents (such as acetylene black) construct an efficient electron transport network between particles, compensating for the potentially high contact resistance between zinc powder particles. Binders (such as PTFE) ensure the structural integrity and flexibility of the electrode sheet, preventing it from easily pulverizing and detaching during charging and discharging. Pressing the mixed electrode materials onto a highly conductive and tough current collector (such as a titanium mesh or tin-plated copper mesh) enables long-range, rapid electron collection and transport, while the mesh or foil structure of the current collector also provides mechanical support for the electrode. This "powder mixing + pressing" electrode fabrication method is a very mature process in the battery industry (similar to nickel-metal hydride batteries and some lithium-ion battery anode processes), with low technology transfer risk and easy industrialization.

[0058] Metal halide perovskite materials and zinc powder are mechanically ball-milled at different mass ratios to generate an artificial metal halide interface layer through in-situ reaction. Then, a suitable current collector is selected, and electrodes are prepared by mixing modified zinc powder, acetylene black, and polytetrafluoroethylene in a specific ratio. For example, the selected bismuth-based metal halide ABX3 is DFPD3BiI6 iodide, and its reaction with zinc powder is as follows:

[0059] Preferably, the metal halide ABX3 has an organic group at the A site with abundant zinc-loving sites, such as one or more of trimethylsulfonium iodide, trimethylsulfonium bromide, 4,4-difluoropiperidine, 1,8-octanediamine, dimethylamine hydrochloride, diethylenetriamine, N,N'-dimethylethylenediamine, etc.

[0060] Preferably, in the metal halide ABX3, the B-site is a metal cation Zn. 2+ Sn 2+ Bi 3+ One or more of them, with the X-position halogen being Cl. – ,Br – and I – One or more of them.

[0061] Preferably, the mass ratio of the metal halide perovskite material to zinc powder is in the range of 1:1 to 1:10.

[0062] Preferably, the zinc powder particle size range is 0 ~ 150 μm.

[0063] Preferably, the mechanical ball milling speed is 100 ~ 1000 r / min, and the ball milling time is 30 min ~ 5 h.

[0064] Preferably, the current collector is selected from ultra-thin titanium mesh or tin-plated copper mesh with high toughness and high conductivity.

[0065] Preferably, the mass ratio of the modified zinc powder, acetylene black, and polytetrafluoroethylene is 8:1:1 or 7:2:1, etc.

[0066] The zinc metal anode preparation method provided in the above embodiments of this application utilizes zinc powder anodes, which have a higher specific surface area than zinc foil. This is beneficial for reducing local current density and suppressing dendrite growth. Constructing an interface layer on its surface is equivalent to adding a functional coating to a 3D framework, achieving both structural optimization and interface modification. The mechanical ball milling-driven "in-situ reaction" makes the interface layer bonded to the zinc powder substrate more firmly than simple physical coating, and it is more resistant to volumetric stress changes during long-term cycling. The "in-situ reaction" characteristic of this method provides more room for imagination in material design. By selecting metal halides that can react specifically with zinc (such as alloying or displacement reactions), the composition and microstructure of the interface layer can be designed, achieving more precise control over zinc deposition behavior. The resulting dense interface layer covers the active sites on the zinc foil surface, enabling a redistribution of the electric field and Zn² at the interface. + The increased ion flux avoids the tip effect, thus fundamentally inhibiting the vertical growth of zinc dendrites. Furthermore, the metal halide artificial interface layer acts as a physical barrier, effectively blocking direct contact between zinc metal and the aqueous electrolyte. On one hand, this avoids the side reaction (hydrogen evolution) between zinc and water, improving coulombic efficiency; on the other hand, it inhibits the chemical corrosion of the zinc anode by the electrolyte, significantly extending the cycle life of the zinc anode.

[0067] This application also provides an aqueous zinc-based battery, comprising a positive electrode, a negative electrode, a separator, and an electrolyte, characterized in that the negative electrode is the zinc metal negative electrode described above, or a zinc metal negative electrode prepared by any of the methods described above.

[0068] Furthermore, the positive electrode material is manganese dioxide, vanadium dioxide, vanadium pentoxide, ammonium vanadate, organic covalent organic framework material, elemental bromine, or elemental iodine; the electrolyte is zinc sulfate solution, zinc trifluoromethanesulfonate solution, zinc bis(trifluoromethanesulfonyl)imide solution, or zinc chloride solution; the separator is a glass fiber type, cellulose type, polyacrylonitrile type, Nafion type, or graphene oxide type separator.

[0069] This application also provides a zinc metal pouch battery, the pouch battery comprising the aforementioned aqueous zinc-based battery.

[0070] It is understandable that applying the above-mentioned negative electrode to complete aqueous zinc-based batteries and pouch batteries will result in improved chemical stability. The interface layer effectively blocks direct contact between the negative electrode and the electrolyte, significantly suppressing hydrogen evolution and corrosion side reactions, thus extending cycle life. Benefiting from the high ionic conductivity of the inorganic framework and the zinc affinity of the organic functional groups, Zn²⁺… + The low transport resistance and uniform deposition within the interface layer result in high reversibility of the battery.

[0071] To facilitate understanding of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0072] Example 1 The preparation of a novel metal halide artificial interface layer modified zinc foil anode includes the following steps: 100 mg of [(CH3)3S]2[ZnBr4] perovskite material was added to 1 mL of N-methylpyrrolidone (NMP) and stirred at room temperature for 30 min. The above solution was then coated onto a 50 μm thick zinc foil using a doctor blade (75 μm coating thickness). After drying at room temperature, a zinc foil modified with a metal halide artificial interface layer was obtained. Figure 3 Then cut it to a diameter of 1.2 cm for later use.

[0073] Example 2 The preparation of a novel multi-component bismuth-based metal halide artificial interface layer modified zinc powder includes the following steps: 100 mg of DFPD3BiI6 (DFPD: 4,4-difluoropiperidine) perovskite material was mechanically ball-milled with zinc powder with a particle size of 50 μm at different mass ratios (1:2, 1:5, 1:10) for 1 h to generate a multi-component bismuth-based halide artificial interface layer in situ. Figure 4 ).

[0074] Example 3 The preparation of a novel multi-component bismuth-based metal halide artificial interface layer modified zinc powder anode includes the following steps: The modified zinc powder, acetylene black, and polytetrafluoroethylene are mixed in a mass ratio of 8:1:1, a small amount of ethanol is added, and finally the mixture is rolled onto a current collector titanium mesh to keep the electrode intact and form a film. The mixture can be cut into zinc powder electrodes with a diameter of 1.2 cm for later use.

[0075] Example 4 Application and performance testing of a novel metal halide artificial interface layer modified zinc metal anode in aqueous zinc-based batteries: Battery assembly: Zinc-zinc symmetric battery, both positive and negative electrodes are zinc metal electrodes modified with metal halide artificial interface layer, electrolyte is 2M ZnSO4 solution, separator is glass fiber separator, assembled into CR2032 type button cell, its assembly sequence is negative electrode shell, zinc metal negative electrode modified with metal halide interface layer, separator, zinc metal negative electrode modified with metal halide interface layer, gasket, spring and positive electrode shell.

[0076] Electrochemical testing: A zinc foil negative electrode modified with a DFPD3BiI6 bismuth-based metal halide artificial interface layer was assembled into a zinc-zinc symmetric coin cell. Electrochemical performance was tested on the Xinwei Battery Testing System with a current density of 2 mA cm⁻¹. -2 The deposition capacity is 2 mAh cm⁻¹ -2 Cyclic performance such as Figure 5 As shown, the zinc metal anode can be stably cycled for over 1500 h under these conditions. A zinc foil anode modified with a zinc-based metal halide artificial interface layer ([(CH3)3S]2[ZnBr4]) was assembled into a zinc-zinc symmetric button cell. Electrochemical performance was tested on the Xinwei Battery Testing System at a current density of 1 mA cm⁻¹. -2 The deposition capacity is 1 mAh / cm³. -2 Cyclic performance such as Figure 6 As shown.

[0077] Example 5 Application and performance testing of a novel metal halide artificial interface layer modified zinc metal anode in zinc-ion full cells: For battery assembly, vanadium dioxide (VO2) was selected as the positive electrode material, with a loading of 1~2 mg cm⁻¹. -2 A zinc foil modified with a metal halide artificial interface layer is used as the negative electrode, a 2M ZnSO4 solution is used as the electrolyte, and a glass fiber membrane is used as the separator. The cells are assembled into a CR2032 type button cell.

[0078] Electrochemical testing: The assembled full cell was subjected to charge-discharge tests on the Newway Battery testing system, such as... Figure 7 As shown, the zinc-ion battery assembled with a zinc metal anode modified by a metal halide artificial interface layer has a good specific capacity.

[0079] The above are merely preferred embodiments of this application, and only specifically describe the technical principles of this application. These descriptions are only for explaining the principles of this application and should not be construed as limiting the scope of protection of this application in any way. Based on this explanation, any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application, as well as other specific embodiments of this application that can be conceived by those skilled in the art without creative effort, should be included within the scope of protection of this application.

Claims

1. A zinc metal negative electrode, characterized in that, It includes a zinc substrate and a metal halide artificial interface layer formed on at least a portion of the surface of the zinc substrate; the metal halide artificial interface layer is formed of a metal halide perovskite material.

2. The zinc metal negative electrode according to claim 1, characterized in that, The metal halide perovskite material has an ABX3 structure, wherein the A-site is an organic group with a zinc-loving site, the B-site is a metal cation, and the X-site is a halide anion.

3. The zinc metal negative electrode according to claim 2, characterized in that, The organic group at the A-position is one or more of trimethylsulfonium iodide, trimethylsulfonium bromide, 4,4-difluoropiperidine, 1,8-octanediamine, dimethylamine hydrochloride, diethylenetriamine, and N,N'-dimethylethylenediamine; the metal cation at the B-position is Zn²⁺. + Sn² + Bi³ + One or more of the following; the X-position halide anion is Cl. - ,Br - I - One or more of them.

4. The zinc metal negative electrode according to claim 1, characterized in that, The zinc substrate is zinc foil or zinc powder.

5. A method for preparing the zinc metal anode as described in claim 4, characterized in that, When the zinc substrate is zinc foil, the following steps are included: The metal halide perovskite material was dissolved in an organic solvent and stirred until a clear solution was obtained. The clarified solution is coated onto the surface of zinc foil; The solvent evaporates at room temperature, thus forming an artificial interface layer of metal halide on the zinc foil surface.

6. The method for preparing the zinc metal anode according to claim 5, characterized in that, The organic solvent is one or more of N-methylpyrrolidone or N,N-dimethylformamide; the concentration of the clarified solution is 30 mg / ml. - ¹ ~ 200mg ml - ¹; the thickness of the doctor blade coating is 50 ~ 200 μm; the thickness of the zinc foil is 10 ~ 200 μm.

7. A method for preparing the zinc metal anode as described in claim 4, characterized in that, When the zinc substrate is zinc powder, the following steps are included: Metal halide perovskite material is mixed with zinc powder and mechanically ball-milled to generate modified zinc powder with a metal halide artificial interface layer on the surface through in-situ reaction. The modified zinc powder, conductive agent, and binder are mixed and pressed onto the current collector to prepare an electrode.

8. The method for preparing the zinc metal anode according to claim 7, characterized in that, The mass ratio of the metal halide perovskite material to zinc powder is 1:1 to 1:10; the particle size range of the zinc powder is 0 to 150 μm; the rotation speed of the mechanical ball mill is 100 to 1000 r / min, and the ball milling time is 30 min to 5 h.

9. The method for preparing the zinc metal anode according to claim 7, characterized in that, The conductive agent is acetylene black, and the binder is polytetrafluoroethylene; the mass ratio of the modified zinc powder, acetylene black, and polytetrafluoroethylene is 8:1:1 or 7:2:1; the current collector is an ultra-thin titanium mesh or a tin-plated copper mesh.

10. The method for preparing a zinc metal negative electrode according to any one of claims 5-7, characterized in that, The metal halide perovskite material has an ABX3 structure, wherein the A-site is an organic group with a zinc-loving site, the B-site is a metal cation, and the X-site is a halide anion.

11. The method for preparing the zinc metal negative electrode according to claim 10, characterized in that, The organic group at the A-position is one or more of trimethylsulfonium iodide, trimethylsulfonium bromide, 4,4-difluoropiperidine, 1,8-octanediamine, dimethylamine hydrochloride, diethylenetriamine, and N,N'-dimethylethylenediamine; the metal cation at the B-position is Zn²⁺. + Sn² + Bi³ + One or more of the following; the X-position halide anion is Cl. - ,Br - I - One or more of them.

12. An aqueous zinc-based battery, comprising a positive electrode, a negative electrode, a separator, and an electrolyte, characterized in that, The negative electrode is the zinc metal negative electrode according to any one of claims 1-4, or the zinc metal negative electrode prepared by the method according to any one of claims 5-11.

13. The aqueous zinc-based battery according to claim 12, characterized in that, The positive electrode material is manganese dioxide, vanadium dioxide, vanadium pentoxide, ammonium vanadate, organic covalent organic framework material, elemental bromine, or elemental iodine; the electrolyte is zinc sulfate solution, zinc trifluoromethanesulfonate solution, zinc bis(trifluoromethanesulfonyl)imide solution, or zinc chloride solution; the separator is glass fiber type, cellulose type, polyacrylonitrile type, Nafion type, or graphene oxide type separator.

14. A zinc metal soft-pack battery, characterized in that, The pouch battery comprises the aqueous zinc-based battery as described in claim 12 or 13.

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