Zinc ion battery, anode material and preparation method thereof

Abstract

The invention discloses a zinc ion battery, an anode material and a preparation method thereof, and belongs to the field of zinc ion batteries. An anode material for a zinc ion battery includes: a zinc foil substrate; the surface of the zinc foil base is wrapped with the interface coating, the interface coating is used for enabling an electric field of the anode material to be evenly distributed, and the interface coating is an artificial interface film composed of aggregates of copper nanoparticles generated through in-situ growth. The anode material of the above example has excellent electrochemical performance.

Description

Technical Field

[0001] This application belongs to the field of electrochemical energy storage devices, especially zinc-ion batteries. In particular, this application relates to a zinc-ion battery, an anode material, and a method for preparing the same. Background Technology

[0002] Due to the need for energy structure transformation and environmental protection, the further development and application of renewable energy is urgently needed. However, solar, geothermal, and wind energy are not consistently stable. Therefore, it is essential to develop new energy storage and conversion systems that are safe, stable, durable, and highly efficient.

[0003] Among various electrochemical energy storage devices, batteries can provide stable power for electronic devices and also serve as energy storage devices to store grid energy. In response to this situation, researchers have proposed a new method to convert energy sources such as solar, wind, and mechanical energy into electrical energy, store it, and then rapidly transmit it back to the grid when necessary.

[0004] Due to their high discharge voltage and mature manufacturing process, lithium-ion batteries (LIBs) have become one of the most widely used electrochemical energy storage devices. However, the lack of key raw materials, high costs, and flammability / explosiveness severely restrict their further development.

[0005] Currently, most lithium-ion batteries use electrolytes that are environmentally polluting and flammable, posing a significant threat to their safety and stable operation. Secondly, current lithium-ion batteries suffer from low ionic conductivity and a tendency to form a solid electrolyte interface layer, thus hindering improvements in energy efficiency and power density. Furthermore, expensive materials and demanding assembly conditions contribute to the relatively high cost of lithium-ion batteries. In short, lithium-ion batteries face significant limitations in their development. Therefore, it is necessary to develop new battery technologies to replace lithium-ion batteries.

[0006] Compared with organic electrolytes in LIBs, metal ion aqueous solution batteries have the potential to become large-scale energy storage batteries due to their advantages such as safety and stability, low cost, simple preparation, and high ionic conductivity.

[0007] Because Zn has a high theoretical capacity and a higher volumetric capacity than Li anodes (2061 mA·h / cm³), it is a more efficient anode. 3 Higher volumetric capacity (5854 mA·h / cm³) 3 Therefore, it can serve as a suitable alternative to traditional LIBs. Furthermore, the high reserves of Zn resources on Earth reduce the production cost of manufacturing ZIBs and make them a viable alternative to traditional lead-acid, Ni-Cd, and Ni-metal hydride (MH) type batteries.

[0008] Furthermore, ZIB uses a relatively safer and simpler electrolyte in its manufacturing process, and it has a longer cycle life, is more environmentally friendly, and exhibits better stability. Therefore, current research focuses on the development of ZIB technology.

[0009] In recent years, researchers have proposed many modification strategies and achieved some success. However, dendrite growth and side reactions are still unavoidable. Summary of the Invention

[0010] Examples of this application provide a zinc-ion battery, an anode material, and a method for preparing the same, which can suppress dendrite growth and side reactions.

[0011] The solution presented in this application example is implemented through the following steps.

[0012] An anode material for zinc-ion batteries includes: Zinc foil substrate; and An interface coating is wrapped around the surface of a zinc foil substrate and used to uniformly distribute the electric field of the anode material. The interface coating is an artificial interface film composed of aggregates of copper nanoparticles generated by in-situ growth.

[0013] If non-in-situ growth is used, copper material needs to be fabricated, and then an adhesive is needed to ensure adhesion. This increases the mass of the negative / anode, clogs the gaps between particles, and, more seriously, makes them more prone to detachment, thus shortening the electrode's lifespan. The in-situ growth method in this application avoids the use of adhesives and also results in stronger adhesion.

[0014] Optionally, the zinc foil substrate surface is pretreated.

[0015] Pretreatment can remove impurities, oil, and oxide layers from the zinc foil surface, preventing these impurities from affecting subsequent reactions. Due to scratches and processing issues, the presence of protrusions on the zinc foil surface can create a tip effect, leading to uneven electric field distribution on the electrodes during use. This uneven electric field distribution increases the zinc ion concentration at the protrusions, and during cycling, zinc ions can deposit on these protrusions, forming zinc dendrites.

[0016] Optionally, the artificial interface film is wetted by the zinc sulfate electrolyte, and the contact angle of the artificial interface film is smaller than the contact angle of the zinc foil substrate surface.

[0017] The contact angle determines and reflects the wettability of the anode surface. Therefore, improving the hydrophilicity of the electrode can promote the contact between electrolyte ions and the negative electrode.

[0018] Specifically, a large contact angle makes the anode surface hydrophobic, thus preventing the negative electrode from contacting water molecules in the electrolyte, but it increases battery polarization, slowing down the battery reaction. Conversely, a small contact angle makes the anode surface hydrophilic, thus promoting contact between electrolyte ions and the negative electrode, reducing polarization, and promoting the reaction.

[0019] Alternatively, the artificial interface film may be distributed on only one surface of the zinc foil.

[0020] For coin cells, the reaction occurs on one surface; therefore, an artificial interface film is prepared on one surface of the zinc foil.

[0021] On the other hand, this application also discloses a zinc-ion battery including the aforementioned anode material.

[0022] Alternatively, the zinc-ion battery is a symmetrical battery.

[0023] On another front, the method for manufacturing an anode material for zinc-ion batteries disclosed in this application includes: Zinc foil is immersed in a mixture of copper sulfate aqueous solution and concentrated ammonia aqueous solution to carry out a displacement reaction, thereby attaching a copper film to the surface of the zinc foil.

[0024] The thickness of the copper film can affect the performance of the anode material, and the thickness can be controlled by the reaction time.

[0025] Optionally, one of the two surfaces of the zinc foil is coated with an interface coating, while the other is covered with polyimide tape to prevent a displacement reaction from occurring on the surface.

[0026] Alternatively, during the displacement reaction, the zinc foil is placed horizontally in the mixture.

[0027] Optionally, the mixture is stored in a container, and the zinc foil is fixed in the container.

[0028] Fixing the zinc foil in place prevents it from accidentally floating during the reaction, which would prevent parts of the foil surface from contacting the reaction solution. This ensures that the zinc foil surface is in full contact with the solution and reacts effectively.

[0029] Beneficial effects: This application discloses a method for in-situ growth of copper nanoparticles as an anode material for zinc-ion batteries and its application. This method grows copper particles on the surface of zinc foil through a simple substitution reaction. By controlling the reaction time, the uniformity of the copper nanoparticle distribution on the Zn anode surface can be optimized. Furthermore, the treated zinc anode surface exhibits a uniform electric field distribution, effectively suppressing surface electrochemical corrosion and dendrite formation, resulting in a lower interfacial transport resistance and significantly improved electrochemical performance of the battery.

[0030] Furthermore, it also has at least the following advantages: 1. The raw materials used in this invention are widely available, environmentally friendly, safe and pollution-free, and the preparation process is simple, reducing costs and showing good application prospects for zinc-ion batteries.

[0031] 2. In this invention, a layer of metallic copper nanoparticles is grown in situ on the surface of the zinc negative electrode, which isolates the negative electrode from direct contact with the electrolyte. The metallic coating of the nano-copper particles has good hydrophilicity, and the modified interface can increase the diffusion kinetics of ions and reduce the occurrence of hydrogen evolution reaction and side reactions.

[0032] 3. After the reaction, a uniform electric field distribution forms on the material surface, effectively suppressing surface electrochemical corrosion and dendrite formation, resulting in a lower interfacial transport resistance and significantly improving the battery's electrochemical performance. Therefore, the copper particles formed in situ provide more nucleation sites. Furthermore, due to their small particle size (the reaction rate can be controlled with ammonia to form more uniform copper particles), the coverage is more dense, resulting in a larger specific surface area and thus a more uniform electric field distribution. This can be corroborated by the morphology of the anode surface after assembly into a battery and cycling. Attached Figure Description

[0033] The following is a brief introduction to the accompanying drawings used in the description.

[0034] Figure 1 Scanning electron microscope (SEM) of Cu-Zn-1(a), Cu-Zn-2(b) and Cu-Zn-3(c) materials in Examples 1, 2 and Comparative Example 2; Figure 2 The peeling / electroplation cycle curves are shown for the symmetrical cells assembled with zinc electrode sheets in Examples 1, 2 and Comparative Example 1. Figure 3 Electrochemical impedance (EIS) curves of symmetrical cells assembled with zinc electrode sheets in Examples 1, 2 and Comparative Example 1; Figure 4 Rate performance curves of the full cells in Examples 1, 2 and Comparative Example 1; Figure 5 The charge-discharge cycle curves and cycle efficiency curves of the full cells in Examples 1, 2 and Comparative Example 1 are shown. Figure 6 Here are the SEM and EDS elemental distribution diagrams for Example 1; Figure 7 The static contact angle test diagrams for Example 1 and Comparative Example 1 are shown. Figure 8 The field emission electron scanning images are those of Example 1(a) and Comparative Example 1(b) after 30 cycles. Detailed Implementation

[0035] This invention provides a method for preparing a zinc-ion battery anode material with in-situ grown copper nanoparticles on the surface of a zinc negative electrode. The prepared copper nanoparticles are uniformly distributed on the zinc foil surface, resulting in a uniform electric field distribution. This successfully suppresses surface electrochemical corrosion and effectively reduces dendrite formation. Because the zinc surface has a uniform and stable copper nanoparticle protective layer, it effectively inhibits the growth of zinc dendrites and induces uniform plating / stripping of zinc ions, thereby extending the battery's stability and cycle life.

[0036] Therefore, this application discloses an anode material for zinc-ion batteries. The anode material includes: a zinc foil substrate; and an interface coating wrapped around the surface of the zinc foil substrate.

[0037] The interface coating is used to functionalize the surface of the zinc foil, thereby ensuring a uniform distribution of the electric field in the anode material (therefore, functionally, the interface coating can also be referred to as an electric field homogenizing layer). Specifically, the interface coating is an artificial interface film composed of aggregates of copper nanoparticles grown in situ.

[0038] Therefore, this artificial interface film can serve as a functional layer to improve the performance of zinc foil, and it can also be used as a protective coating to protect the zinc anode.

[0039] Furthermore, based on the anode material, the example also discloses a zinc-ion battery that includes the anode material. In some examples, based on research and other considerations, the above anode material can be used to construct a zinc-ion battery in the form of a symmetrical cell.

[0040] The zinc foil substrate surface is pre-treated to improve surface flatness, which facilitates the uniform distribution of copper particles and improves the uniformity of the electric field distribution. Flattening can be achieved through operations such as grinding or polishing.

[0041] For the application of battery assembly, zinc sulfate electrolyte is used in this example. Therefore, in this example, the artificial interface film of the anode material is wetted by the zinc sulfate electrolyte, and the contact angle of the artificial interface film is smaller than the contact angle of the zinc foil substrate surface, thereby allowing the electrolyte solution to have more sufficient contact with the anode material.

[0042] Similarly, in the application of button cells, the artificial interface film can be distributed only on one surface of the zinc foil through process control.

[0043] The example also discloses the manufacturing method of the above anode materials.

[0044] Specifically, methods for manufacturing anode materials for zinc-ion batteries include: Zinc foil is immersed in a mixture of copper sulfate aqueous solution and concentrated ammonia aqueous solution to carry out a displacement reaction, thereby attaching a copper film to the surface of the zinc foil.

[0045] The use of ammonia water allows for the formation of a complex, Cu(NH3)4, during the reaction. 2+ To avoid rapid reactions between Zn and Cu, uniform spherical nanoparticles are formed, thereby improving the uniformity of the electric field distribution at the anode. The electric field uniformity of the anode material in this application can be assessed by CA curves and... Figure 2 The long loop shown Figure 3 This is corroborated by the impedance and other electrochemical tests shown.

[0046] Furthermore, for coin cells, an interface coating is formed on one of the two surfaces of the zinc foil to prevent displacement reactions from occurring on that surface. In other words, an artificial interface film is created on one surface of the zinc foil.

[0047] Furthermore, in the example above, during the displacement reaction, the zinc foil is placed horizontally in the mixture. Specifically, this can be achieved by storing the mixture in a container and securing the zinc foil within that container. In this way, air bubbles cannot float the zinc foil during the displacement reaction, thus ensuring that the designed surface of the zinc foil reacts reliably.

[0048] More specifically, the example also discloses a method for preparing a zinc-ion battery anode material by in-situ growth of copper nanoparticles, which includes the following steps: 1) Cut zinc foil (Zn) and pre-treat it.

[0049] The zinc foil is cut to a size of (5~10)cm × (5~10)cm. The thickness of the zinc foil is approximately 0.1mm.

[0050] The pretreatment involves immersing the cut zinc foil in dilute hydrochloric acid (0.1–0.5 mol / L) for 30 seconds, followed by ultrasonic treatment for 0.5 hours to remove the surface oxide layer and impurities. After ultrasonic treatment, the zinc foil is removed and washed and dried.

[0051] 2) Weigh out CuSO4·5H2O and measure out deionized water. Mix and stir them together to prepare a solution. Then, use a graduated cylinder to measure concentrated ammonia solution and add the ammonia solution dropwise to the mixed solution. Mix the solutions and stir continuously for 15-30 minutes.

[0052] The CuSO4 solution concentration is 0.01 ~ 5 mol / L, and the ammonia water used for dropwise addition is a concentrated ammonia solution with a mass fraction of 25% ~ 28%.

[0053] 3) Place the zinc foil to be treated into the prepared solution and react, controlling the reaction time, and then wash with deionized water and anhydrous ethanol.

[0054] In this step, the zinc foil is placed in the prepared solution and reacted for 30-1200 seconds. After the reaction is complete, the zinc foil is removed with tweezers and repeatedly rinsed with deionized water to remove the CuSO4 solution and residues from the surface of the zinc foil, and then rinsed with C2H6O.

[0055] 4) Then place it in a drying oven to dry, and obtain zinc-ion battery anode material with in-situ grown nano-copper particles, labeled ZnCu.

[0056] The drying process is carried out in a vacuum drying oven, with the drying temperature controlled at 50~70℃ and the drying time at 8~12 hours. Vacuum drying prevents the obtained material from reacting with oxygen and being oxidized, and also allows the zinc foil surface to dry rapidly.

[0057] The example also discloses the application of the above-described method for fabricating anode materials for zinc-ion batteries in reducing dendrite growth in aqueous zinc-ion batteries. This application is achieved and implemented by forming a modification layer on the surface of a zinc foil current collector, which enables uniform nucleation and growth of zinc ions, using the method for preparing aqueous zinc-ion anode materials.

[0058] Example 1 1. Preparation of negative electrode materials Cut the zinc foil into 5cm x 5cm sheets, flatten them, and then immerse them in hydrochloric acid (0.1 mol / L) and sonicate for 30 seconds to remove the surface oxide film and impurities. Do not immerse for too long to avoid reducing the thickness of the zinc foil. Remove the sonicated zinc sheets and rinse repeatedly with anhydrous ethanol and deionized water to remove the surface hydrochloric acid. Allow them to air dry naturally before use as a substrate.

[0059] Protect one side of the dried zinc foil to ensure it does not participate in the displacement reaction. Specifically, apply polyimide tape to the bottom surface of the zinc foil for protection. Secure the protected zinc foil in the petri dish with the reaction-participating side facing upwards (i.e., the top surface of the zinc foil), ensuring the zinc foil is flat. Weigh the reagent CuSO4·5H2O and measure 50 mL of deionized water. Add 1.32 g of copper sulfate to the deionized water and stir thoroughly for 15 minutes to obtain a 0.1 M blue CuSO4 solution. In a fume hood, under protection, use a graduated cylinder to measure 20 mL of 25% concentrated ammonia solution. Add the ammonia solution dropwise to the CuSO4 solution, mix, and stir continuously for 30 minutes, until the solution changes from light blue to cloudy and then to dark blue. Pour the mixture into the petri dish, ensuring the top surface of the zinc foil is completely submerged. Start timing and control the reaction (displacement treatment) time to 8 minutes. Once the reaction time is reached, the zinc foil is quickly removed and its surface is repeatedly rinsed with deionized water to remove any residual mixed solution and other reaction products. Then, it is rinsed with C2H6O and placed in a vacuum drying oven to dry at 60°C for 12 hours. This process yields an in-situ grown zinc-ion battery anode material of nano-copper particles, denoted as Cu-Zn-1.

[0060] In this embodiment, polyimide tape is first applied to one surface (lower surface) of the zinc foil to protect it and prevent uneven reaction on the other side. This example employs a simple substitution reaction on the zinc foil surface to form in-situ grown copper nanoparticles. The experimental procedure is simple, highly reproducible, and significantly shortens the synthesis time of the anode material. The experimental method has good universality. The obtained Cu-Zn-1 has a uniform and clear morphology.

[0061] 2. Assemble the battery The prepared zinc anode material was cut into 12mm diameter sheets using a slicer, with two identical sheets serving as the positive and negative electrodes. One of the cut electrodes was placed in the positive electrode shell, with the uncoated side in contact with the shell. A glass fiber separator was then placed in the shell, and 120µL of 2M ZnSO4 was added as the electrolyte using a pipette. Another zinc anode sheet was then placed on top of the separator, with the uncoated side in contact with a stainless steel gasket. The gasket and spring were then added sequentially, and finally the negative electrode shell was attached. The battery was then sealed using a battery packaging machine, resulting in a modified zinc anode aqueous zinc-ion symmetric button cell, labeled as a Zn@Cu-Zn-1 / / Zn@Cu-Zn-1 symmetric cell.

[0062] As above, the prepared material was cut into 12mm diameter electrode sheets using a slicer. Copper foil and Zn@Cu-Zn-1 were used as the positive and negative electrode sheets, respectively. The copper foil was placed in the positive electrode shell, followed by a glass fiber separator. 120µL of 2M ZnSO4 was added as the electrolyte using a pipette. Another Zn@Cu-Zn-1 negative electrode sheet was then placed on top of the separator. The uncoated side was brought into contact with a stainless steel gasket. The gasket and spring were then placed in sequence, and the negative electrode shell was attached. The battery was then encapsulated using a battery encapsulation machine to obtain a modified Cu / / Zn@Cu-Zn-1 / / half-cell. The manganese-based positive electrode, zinc foil negative electrode, and separator were assembled into the casing, and an electrolyte consisting of 2M ZnSO4 was injected. This resulted in a Zn@Cu-Zn-1 / / zinc salt / / manganese-based positive electrode aqueous zinc-ion battery.

[0063] Example 2 1. Preparation of negative electrode materials Cut the zinc foil into 5cm x 5cm sheets, flatten them, and then immerse them in hydrochloric acid (0.1 mol / L) and sonicate for 30 seconds to remove the surface oxide film and impurities. Do not immerse for too long to avoid reducing the thickness of the zinc foil. Remove the sonicated zinc sheets and rinse repeatedly with anhydrous ethanol and deionized water to remove the surface hydrochloric acid. Allow them to air dry naturally before use as a substrate.

[0064] Protect one side of the dried zinc foil to ensure it does not participate in the displacement reaction. Specifically, apply polyimide tape to the bottom surface of the zinc foil for protection. Secure the protected zinc foil in the petri dish with the reaction-participating side facing upwards (i.e., the top surface of the zinc foil), ensuring the zinc foil is flat. Weigh the reagent CuSO4·5H2O and measure 50 mL of deionized water. Add 1.32 g of copper sulfate to the deionized water and stir thoroughly for 15 minutes to obtain a 0.1 M blue CuSO4 solution. In a fume hood, under protection, use a graduated cylinder to measure 20 mL of 25% concentrated ammonia solution. Add the ammonia solution dropwise to the CuSO4 solution, mix, and stir continuously for 30 minutes, until the solution changes from light blue to cloudy and then to dark blue. Pour the mixture into the petri dish, ensuring the top surface of the zinc foil is completely submerged. Start timing and control the reaction (displacement treatment) time to 2 minutes. Once the reaction time is reached, the zinc foil is quickly removed and its surface is repeatedly rinsed with deionized water to remove any residual mixed solution and other reaction products. Then, it is rinsed with C2H6O and placed in a vacuum drying oven to dry at 60°C for 12 hours. This process yields an in-situ grown copper nanoparticle zinc-ion battery anode material, denoted as Cu-Zn-2.

[0065] 2. Assemble the battery The assembly is the same as in Example 1, except that the negative electrode material is replaced with Cu-Zn-2.

[0066] Comparative Example 1 1. Preparation of negative electrode materials Cut the zinc foil into 5cm x 5cm sheets, flatten them, and then immerse them in dilute hydrochloric acid (0.1 mol / L) and sonicate for 30 seconds to remove the surface oxide film and impurities. Do not immerse for too long to avoid reducing the thickness of the zinc foil. Remove the sonicated zinc sheets and rinse repeatedly with anhydrous ethanol and deionized water to remove the surface dilute hydrochloric acid. Allow them to air dry naturally. These are then used as unreplaced bare zinc.

[0067] 2. Assemble the battery The prepared zinc anode material was cut into 12mm diameter sheets using a slicer, with two identical sheets serving as the positive and negative electrodes. One of the cut electrodes was placed in the positive electrode shell, followed by a glass fiber separator. 300µL of 2M ZnSO4 was added as the electrolyte using a pipette, and then another zinc anode sheet was placed on top of the separator. Next, a spacer and a spring were added in sequence, and finally the negative electrode shell was attached. The battery was then sealed using a battery packaging machine, resulting in a modified zinc anode aqueous zinc-ion symmetric button cell, labeled as a Zn / / Zn symmetric button cell.

[0068] As above, the prepared material was cut into 12mm diameter electrode sheets using a slicer. Copper foil and treated zinc foil were used as the positive and negative electrode sheets, respectively. The copper foil was placed in the positive electrode shell, followed by a glass fiber separator. 120µL of 2M ZnSO4 was added as the electrolyte using a pipette. Another zinc negative electrode sheet was then placed on top of the separator. Next, a gasket and a spring were added in sequence, and the negative electrode shell was attached. The battery was then sealed using a battery packaging machine to obtain a modified Cu / / Zn / / half-cell.

[0069] The manganese-based positive electrode, zinc sheet negative electrode, and separator are assembled into the shell, and an electrolyte is injected. The electrolyte is composed of 2M ZnSO4, and the shell is packaged into a Zn / / zinc salt / / manganese-based positive electrode aqueous zinc-ion battery.

[0070] Comparative Example 2 1. Preparation of negative electrode materials Cut the zinc foil into 5cm x 5cm sheets, flatten them, and then immerse them in hydrochloric acid (0.1 mol / L) and sonicate for 30 seconds to remove the surface oxide film and impurities. Do not immerse for too long to avoid reducing the thickness of the zinc foil. Remove the sonicated zinc sheets and rinse repeatedly with anhydrous ethanol and deionized water to remove the surface hydrochloric acid. Allow them to air dry naturally before use as a substrate.

[0071] Protect one side of the dried zinc foil to ensure it does not participate in the displacement reaction. Specifically, apply polyimide tape to the bottom surface of the zinc foil for protection. Secure the protected zinc foil in the petri dish with the reaction-participating side facing upwards (i.e., the top surface of the zinc foil), ensuring the zinc foil is flat. Weigh the reagent CuSO4·5H2O, measure 50 mL of deionized water, and add 1.32 g of copper sulfate reagent to the deionized water. Stir thoroughly for 15 minutes to obtain a 0.1 M blue CuSO4 solution. Pour the CuSO4 solution into the petri dish, ensuring the top surface of the zinc foil is completely submerged in the CuSO4 solution, and start timing, controlling the reaction (displacement treatment) time to 8 minutes. Once the reaction time is reached, the zinc foil is quickly removed and the surface of the zinc foil is repeatedly rinsed with deionized water to remove residual CuSO4 solution and other reaction products. Then, it is rinsed with C2H6O. After rinsing, it is placed in a vacuum drying oven to dry at a temperature of 60°C for 12 hours. Finally, the zinc-ion battery anode material with in-situ grown nano-copper particles is obtained, denoted as Cu-Zn-3.

[0072] 2. Assemble the battery The assembly is the same as in Example 1, except that the negative electrode material is replaced with Cu-Zn-3.

[0073] The products in Examples 1, 2, Comparative Example 1, and Comparative Example 2 were tested, and the results are as follows.

[0074] from Figure 1 The SEM scans of a1, a2, and a3 show that the Cu-Zn-1 (Example 1) material grows uniform nanoparticles on the zinc foil surface. These nanoparticles are uniform in size and have the same morphology.

[0075] from Figure 1 The SEM scans of a1, a2, and a3 show that the Cu-Zn-2 (Example 2) material only grows a small number of nanoparticles due to the short reaction time, while the other part only has a spherical prototype.

[0076] from Figure 1 The SEM scan images of c1, c2, and c3 show that Cu-Zn-3 (Comparative Example 2) material cannot form particles on the zinc foil surface due to the absence of ammonia water, but can only form a mixed product of flakes and small particles (flower-like nanosheet morphology).

[0077] Figure 2 The cyclic curves are for Example 1 (Cu-Zn-1), Example 2 (Cu-Zn-2), and Comparative Example 1 (Bare Zn). At a current density of 1 mA·cm⁻¹ -2 Surface capacity 1 mAh·cm-2 Under the test conditions, the bare zinc symmetric cell short-circuited after nearly 100 hours of operation due to the generation of passivation byproducts and the evolution of hydrogen.

[0078] Among them, the Cu-Zn-2 battery experienced a short circuit after 450 hours. In contrast, the Cu-Zn-1 material exhibited a significantly longer cycle life than Cu-Zn-2, exceeding 650 hours. Minimal electrochemical polarization indicates a low nucleation barrier for Zn and highly uniform nucleation. Overall, after complete replacement of copper particles on the zinc foil surface, Cu-Zn-1 material demonstrated superior cycle performance compared to untreated bare Zn and Cu-Zn-2, which did not fully produce copper particles.

[0079] Figure 3 The figures show symmetrical electrochemical impedance spectroscopy (EIS) curves for the zinc electrode assemblies in Examples 1, 2, and Comparative Example 1. The Zn@Cu-Zn-1 ||Zn@Cu-Zn-1 battery exhibits low impedance in the EIS spectrum, demonstrating good charge transfer capability. This further illustrates that the Cu-Zn-1 material is beneficial for reducing battery resistance.

[0080] Figure 4 Rate performance tests were conducted on three types of full cells at current densities of 0.2, 0.5, 1, 2, and 5 A / g. Zn@Cu-Zn-1 || V2O5 exhibited good rate performance, indicating excellent stability of this material.

[0081] Figure 5 The stability curves of the batteries after more than 300 cycles at a current density of 1 A / g are shown. The discharge specific capacity of the three batteries all showed a decreasing trend after cycling.

[0082] Initially, the Zn@TM / NC ||V2O5 battery exhibited the highest specific capacity, approximately 205 mAh / g, roughly the same as the other two types. However, as cycling progressed, both the Zn@TM / NC and Zn@Ti-MOF ||V2O5 batteries showed a rapid decrease in specific capacity, while the Zn@Cu-Zn-1 ||V2O5 battery showed a slower decrease.

[0083] In over 300 cycles, both the Zn@Cu-Zn-1||V2O5 and Zn@Cu-Zn-2||V2O5 batteries exhibited high efficiency, approximately 100%. However, the Zn@Ti-MOF||V2O5 battery showed a sudden and significant drop in efficiency after just over 50 cycles, resulting in poor efficiency. Therefore, as shown in the figure, the Zn@Cu-Zn-1||V2O5 battery demonstrated superior cycling stability at a current density of 1 A / g.

[0084] from Figure 6 According to the elemental distribution diagram, Cu is uniformly distributed on the surface of the zinc foil.

[0085] Figure 7 The static contact angles of Example 1 and Comparative Example 1 show that the construction of the interface coating effectively improves the wettability of the zinc foil surface, which helps to improve the electrode polarization effect of zinc ions during the deposition / dissolution process.

[0086] Figure 8 The SEM image of the electrode surface after 30 cycles shows that the Zn@Cu-Zn-1 electrode surface has a smoother morphology and no large amount of by-products.

[0087] The above description of the structure, features and effects of this application is based on the embodiments shown in the drawings. The above are only preferred embodiments of this application. However, this application does not limit the scope of implementation to what is shown in the drawings. Any changes made in accordance with the concept of this application, or modifications to equivalent embodiments, that do not exceed the spirit covered by the specification and drawings, should be within the protection scope of this application.

Claims

1. An anode material for zinc-ion batteries, characterized in that, The anode material includes: Zinc foil substrate; and An interface coating wrapped around a zinc foil substrate and used to uniformly distribute the electric field of the anode material, the interface coating being an artificial interface film composed of aggregates of copper nanoparticles generated by in-situ growth.

2. The anode material according to claim 1, characterized in that, The zinc foil substrate surface has been pretreated.

3. The anode material according to claim 1 or 2, characterized in that, The artificial interface film is wetted by the zinc sulfate electrolyte, and the contact angle of the artificial interface film is smaller than that of the zinc foil substrate surface, thus exhibiting hydrophilicity.

4. The anode material according to claim 1, characterized in that, The artificial interface film is distributed on only one surface of the zinc foil.

5. A zinc-ion battery, characterized in that, Includes the anode material as described in any one of claims 1 to 4.

6. The zinc-ion battery according to claim 5, characterized in that, Zinc-ion batteries are symmetrical batteries.

7. A method for manufacturing an anode material for zinc-ion batteries, characterized in that, The method includes: Zinc foil is immersed in a mixture of copper sulfate aqueous solution and concentrated ammonia aqueous solution to carry out a displacement reaction, thereby attaching a copper film to the surface of the zinc foil.

8. The method according to claim 7, characterized in that, One of the two surfaces of the zinc foil is coated with an interface coating, and the other surface is covered with polyimide tape to prevent a displacement reaction from occurring on the surface.

9. The method according to claim 7 or 8, characterized in that, During the displacement reaction, the zinc foil is placed horizontally in the mixture; Optionally, the mixture is stored in a container, and the zinc foil is fixed in the container.

10. The application of the method according to any one of claims 7 to 9 in reducing dendrite growth in aqueous zinc-ion batteries, characterized in that, The method for preparing aqueous zinc ion anode materials described above forms a modification layer on the surface of a zinc foil current collector that enables uniform nucleation and growth of zinc ions.

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