High-performance magnesium-aluminum-tin-bismuth-indium alloy anode and preparation method thereof

Abstract

A high-performance magnesium-aluminum-tin-bismuth-indium alloy anode comprises a quinary alloy matrix and a functional layer, the quinary alloy matrix is composed of 84-92 wt% of magnesium, 5-12 wt% of aluminum, 2-3 wt% of tin, 0.5-2 wt% of bismuth and 0.1-1 wt% of indium, and the functional layer wraps the surface of the quinary alloy matrix and is used for isolating electrolyte corrosion, reducing interface impedance and improving magnesium ion transmission efficiency. The quinary alloy matrix and the functional layer act synergistically to form the anode, the magnesium-aluminum-tin-bismuth-indium alloy anode is of an amorphous / nanocrystalline structure, and the microstructure of the magnesium-aluminum-tin-bismuth-indium alloy anode is formed through a rapid solidification technology, so that local current concentration is reduced, formation and growth of dendritic crystals are inhibited, and the service life of the magnesium-aluminum-tin-bismuth-indium alloy anode is prolonged. According to the magnesium-aluminum-tin-bismuth-indium alloy anode, magnesium, aluminum, tin, bismuth and indium elements in a specific proportion are adopted, and through the amorphous / nanocrystalline structural design and surface magnesium sulfide nanolayer coating, the anode can effectively inhibit formation and growth of dendritic crystals in the charging and discharging process, and the energy efficiency of the anode is greatly improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of magnesium battery anode materials, and specifically relates to a high-performance magnesium-aluminum-tin-bismuth-indium alloy anode and a preparation method thereof. The invention relates to a five-element alloy composite anode composed of magnesium, aluminum, tin, bismuth and indium and a preparation method thereof, which solves the problems of dendrite growth, interface corrosion and cycle stability of magnesium metal anodes through the synergistic effect of multiple elements. Background Art

[0002] With the growing global demand for efficient energy storage systems, magnesium batteries, as an emerging energy storage technology, have attracted widespread attention due to their high energy density, abundant magnesium resources, and good safety. The high theoretical specific capacity and low redox potential of magnesium metal anodes make them highly promising anode materials for magnesium batteries. However, conventional magnesium metal anodes face a series of severe challenges in practical application, severely hindering the commercialization of magnesium batteries.

[0003] Magnesium metal anodes are prone to dendrite growth during the charge and discharge process. Dendrites can not only pierce the separator, causing internal short circuits in the battery, leading to sudden battery failure and even safety hazards, but also increase the contact area between the electrode and the electrolyte, accelerating the occurrence of interfacial side reactions, and reducing the battery's Coulombic efficiency and cycle stability. Furthermore, when the magnesium metal anode comes into contact with the electrolyte, interfacial passivation occurs, forming a dense passivation layer that hinders the transmission of magnesium ions, increases interfacial impedance, and affects the battery's rate performance and charge and discharge efficiency. Summary of the Invention

[0004] In view of the shortcomings of the existing technology, the purpose of the present invention is to provide a high-performance magnesium-aluminum-tin-bismuth-indium alloy anode and a preparation method thereof, so as to solve the problem that the existing technology lacks a magnesium battery anode that can effectively inhibit dendrite growth and interface passivation while having high stability, low cost and rapid ion transport capability.

[0005] In order to achieve the above object, the present invention is implemented through the following technical solution: a high-performance magnesium-aluminum-tin-bismuth-indium alloy anode, comprising: A five-element alloy matrix, the five-element alloy matrix consisting of 84-92 wt% magnesium, 5-12 wt% aluminum, 2-3 wt% tin, 0.5-2% bismuth and 0.1-1 wt% indium; A functional layer, which is coated on the surface of the five-element alloy substrate and is used to isolate electrolyte corrosion, reduce interface impedance, and improve magnesium ion transmission efficiency; Among them, the five-element alloy matrix and the functional layer work together to form a magnesium-aluminum-tin-bismuth-indium alloy anode. The magnesium-aluminum-tin-bismuth-indium alloy anode has an amorphous / nanocrystalline structure, and its microstructure is formed by rapid solidification technology to reduce local current concentration and inhibit the formation and growth of dendrites.

[0006] Furthermore, the functional layer is a magnesium sulfide nanolayer, and the thickness of the magnesium sulfide nanolayer is 50 to 200 nm.

[0007] Furthermore, the magnesium-aluminum-tin-bismuth-indium alloy anode has high energy density and long cycle life, can operate stably in a magnesium-ion battery, and the functional layer significantly improves the corrosion resistance and interface stability of the anode.

[0008] Furthermore, the amorphous / nanocrystalline structure of the magnesium-aluminum-tin-bismuth-indium alloy anode can reduce local current concentration and optimize the uniformity of the electrochemical reaction, thereby improving the overall performance of the battery. The functional layer further enhances the chemical stability and interface compatibility of the anode through the action of the magnesium sulfide nanolayer, ensuring the long-term stability of the anode in the battery.

[0009] A method for preparing a high-performance magnesium-aluminum-tin-bismuth-indium alloy anode comprises the following steps: S1. Raw material preparation: Weigh the required magnesium, aluminum, tin, bismuth and indium raw materials according to mass percentage and place them in a crucible; S2. Heating and melting: Place the crucible in a vacuum furnace, control the heating rate, and melt at high temperature to ensure uniform alloy composition; S3, cooling and rolling: rapidly water-cooling the quinary alloy matrix smelted in S2 to form an amorphous alloy ingot, and then rolling the amorphous alloy ingot into an alloy foil with a thickness of 100 μm; S4, chemical dealloying treatment: immersing the alloy foil after rolling in S3 in mixed acid to form a porous structure to increase the surface area and reaction activity; S5, surface functional layer coating: immerse the alloy foil after gold removal in S4 in a sodium sulfide solution for reaction to generate a magnesium sulfide nanolayer to improve corrosion resistance and interface stability; S6. Performance testing: Assemble the alloy foil processed in S5 into a battery, test its electrochemical performance, and verify the high performance of the anode.

[0010] Furthermore, in the heating and melting step, the heating rate below 500°C is 8-12°C / minute, and the heating rate above 500°C is 3-6°C / minute. After heating to above the melting point, the smelting is carried out under argon protection.

[0011] Furthermore, in the cooling and rolling step, the smelted five-element alloy is quickly water-cooled to room temperature and then rolled at a rolling temperature of 100-200° C. to ensure that the thickness of the alloy foil is uniform.

[0012] Furthermore, in the chemical dealloying step, the mixed acid used is composed of hydrochloric acid and nitric acid in a volume ratio of 3:1.

[0013] Furthermore, in the surface functional layer covering step, the solution is a 0.1M Na2S solution.

[0014] Furthermore, in the performance testing step, the alloy foil wrapped with the magnesium sulfide nanolayer was assembled into a symmetrical battery, and 0.5M Mg(TFSI)2 / DME was used as the electrolyte to test the electrochemical performance of the battery.

[0015] The beneficial effects of the present invention are: 1. Synergistic effect of the five-element alloy: Aluminum and bismuth can effectively inhibit intergranular corrosion. Aluminum can improve the corrosion resistance of the alloy and enhance the alloy's oxidation resistance and corrosion resistance. Bismuth refines the grains and reduces local current concentration. Indium increases the ion transfer rate and reduces the interface impedance. Tin can enhance the current output efficiency of the anode material, and the alloy formed with magnesium, aluminum, bismuth, and indium can inhibit the rapid dissolution of other metals, slow down the corrosion rate of the anode material, and extend the service life. Through this synergistic effect, the dendrite inhibition efficiency is improved by 40%. Compared with traditional magnesium alloy anodes, dendrite growth is significantly reduced, and the cycle stability of the battery is greatly improved.

[0016] 2. High electrochemical activity: The synergistic effect of the components in the quinary alloy improves the electrochemical activity of the anode, giving it a higher discharge capacity and more stable cycle performance in magnesium batteries.

[0017] 3. Good corrosion resistance: The addition of bismuth and aluminum can effectively inhibit the corrosion of magnesium alloy in the electrolyte, thereby extending the service life of the battery.

[0018] 4. High performance: The five-element alloy anode of this application is suitable for high-rate charge and discharge scenarios. After 300 charge and discharge cycles at a rate of 0.5 times the rated capacity, the capacity retention rate is greater than or equal to 90%. The coulombic efficiency can reach 96.2% compared with the 30-50% of traditional magnesium anodes, and the energy efficiency is greatly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Other features, objects and advantages of the present invention will become more apparent upon reading the detailed description of non-limiting embodiments with reference to the following drawings: Figure 1 This is a schematic structural diagram of a high-performance magnesium-aluminum-tin-bismuth-indium alloy anode according to the present invention; Figure 2 The figure is a schematic flow chart of a method for preparing a high-performance magnesium-aluminum-tin-bismuth-indium alloy anode according to the present invention. DETAILED DESCRIPTION

[0020] In order to make the technical means, creative features, objectives and effects achieved by the present invention easier to understand, the present invention is further described below in conjunction with specific implementation methods.

[0021] [Magnesium-aluminum-tin-bismuth-indium alloy anode according to an embodiment of the present invention] like Figure 1 As shown, the present invention provides a technical solution for a high-performance magnesium-aluminum-tin-bismuth-indium alloy anode, which includes: A five-element alloy matrix, the five-element alloy matrix consisting of 84-92 wt% magnesium, 5-12 wt% aluminum, 2-3 wt% tin, 0.5-2% bismuth and 0.1-1 wt% indium; A functional layer, which is coated on the surface of the five-element alloy substrate and is used to isolate electrolyte corrosion, reduce interface impedance, and improve magnesium ion transmission efficiency; Among them, the five-element alloy matrix and the functional layer work together to form a magnesium-aluminum-tin-bismuth-indium alloy anode. The magnesium-aluminum-tin-bismuth-indium alloy anode has an amorphous / nanocrystalline structure, and its microstructure is formed by rapid solidification technology to reduce local current concentration and inhibit the formation and growth of dendrites.

[0022] In order to isolate electrolyte corrosion, the functional layer is a magnesium sulfide nanolayer, and the thickness of the magnesium sulfide nanolayer is 50 to 200 nm.

[0023] In order to be able to work stably in magnesium ion batteries, the magnesium-aluminum-tin-bismuth-indium alloy anode has high energy density and long cycle life, and can work stably in magnesium ion batteries. The functional layer significantly improves the corrosion resistance and interface stability of the anode.

[0024] In order to improve the overall performance of the anode, the amorphous / nanocrystalline structure of the magnesium-aluminum-tin-bismuth-indium alloy anode can reduce local current concentration and optimize the uniformity of the electrochemical reaction, thereby improving the overall performance of the battery. The functional layer further enhances the chemical stability and interface compatibility of the anode through the action of the magnesium sulfide nanolayer, ensuring the long-term stability of the anode in the battery.

[0025] [Method for preparing a magnesium-aluminum-tin-bismuth-indium alloy anode according to an embodiment of the present invention] like Figure 2 As shown, in order to facilitate preparation and production, the present invention provides a technical solution for a method for preparing a high-performance magnesium-aluminum-tin-bismuth-indium alloy anode: a method for preparing a high-performance magnesium-aluminum-tin-bismuth-indium alloy anode, which comprises the following steps: S1. Raw material preparation: Weigh the required magnesium, aluminum, tin, bismuth and indium raw materials according to mass percentage and place them in a crucible; S2. Heating and melting: Place the crucible in a vacuum furnace, control the heating rate, and melt at high temperature to ensure uniform alloy composition; S3, cooling and rolling: rapidly water-cooling the quinary alloy matrix smelted in S2 to form an amorphous alloy ingot, and then rolling the amorphous alloy ingot into an alloy foil with a thickness of 100 μm; S4, chemical dealloying treatment: immersing the alloy foil after rolling in S3 in mixed acid to form a porous structure to increase the surface area and reaction activity; S5, surface functional layer coating: immerse the alloy foil after gold removal in S4 in a sodium sulfide solution for reaction to generate a magnesium sulfide nanolayer to improve corrosion resistance and interface stability; S6. Performance testing: Assemble the alloy foil processed in S5 into a battery, test its electrochemical performance, and verify the high performance of the anode.

[0026] To facilitate heating, in the heating and melting step, the heating rate below 500°C is 8-12°C / minute, and the heating rate above 500°C is 3-6°C / minute. After heating to above the melting point, the smelting is carried out under argon protection.

[0027] In order to ensure uniform thickness of the alloy foil, in the cooling and rolling step, the smelted five-element alloy is rapidly water-cooled to room temperature and then rolled, with the rolling temperature being 100-200°C.

[0028] In order to ensure uniform alloy composition, in the chemical dealloying step, the mixed acid used is composed of hydrochloric acid and nitric acid in a volume ratio of 3:1.

[0029] In order to generate a uniform and dense magnesium sulfide nanolayer, in the surface functional layer covering step, the solution is a 0.1 M Na2S solution.

[0030] In order to accurately evaluate the electrochemical performance of the anode, in the performance testing step, the alloy foil wrapped with the magnesium sulfide nanolayer was assembled into a symmetrical cell, and 0.5M Mg(TFSI)2 / DME was used as the electrolyte to test the electrochemical performance of the cell.

[0031] According to the preparation method of a high-performance magnesium-aluminum-tin-bismuth-indium alloy anode presented in this application, it is divided into the following embodiments according to the different component contents and different melting temperatures. The specific contents and melting temperatures are as follows: A preparation process of a high-performance magnesium-aluminum-tin-bismuth-indium alloy anode is as follows: S1. Raw material preparation: Weigh the required magnesium, aluminum, tin, bismuth, and indium raw materials according to the mass ratio and place the raw materials in a crucible; S2. Heating and melting: placing the crucible in a vacuum furnace, keeping the temperature at 100°C for one hour, heating at a rate of 10°C per minute below 500°C, and heating at a rate of 5°C per minute above 500°C to 800°C until the temperature is above the melting point, melting under argon protection, and rapidly cooling with water to obtain an amorphous alloy ingot; S3. Alloy matrix preparation: The amorphous alloy ingot is rolled into a foil with a thickness of 100 μm. The foil is immersed in a mixed acid of hydrochloric acid and nitric acid with a volume ratio of 3:1 for chemical dealloying to form a porous structure to increase the surface area and reaction activity; S4. Functional layer coating: The chemically dealloyed foil is immersed in a 0.1M sodium sulfide (Na2S) solution and reacted at 80°C for 2 hours to generate a magnesium sulfide (MgS) nanolayer with uniform thickness. The reaction time and temperature need to be controlled to ensure that the thickness of the magnesium sulfide nanolayer is in the range of 50 to 200 nm.

[0032] S5. Anode preparation: Assemble the surface-sulfurized alloy foil into a symmetrical battery. Use the treated alloy foil as the anode and cathode, respectively, and place them at the two electrode positions of the battery. Place a porous membrane between the two electrodes to ensure that the electrolyte can pass freely but prevent direct contact between the electrodes. Inject 0.5M Mg(TFSI)2 / DME electrolyte to ensure that the electrolyte fully infiltrates the electrodes and the membrane. Then encapsulate the battery to ensure a good seal to prevent electrolyte leakage.

[0033] Example 1: In this embodiment 1, the aluminum and tin contents are relatively high (10% and 3%, respectively), which helps to significantly improve the corrosion resistance of the anode and inhibit dendrite growth. High-temperature smelting at 800°C can help form a uniform amorphous structure and further optimize the microstructure of the alloy. This embodiment can improve the corrosion resistance and mechanical strength of the anode, significantly inhibit the formation and growth of dendrites, and extend the cycle life of the battery. It is suitable for application scenarios with high requirements for corrosion resistance and mechanical strength.

[0034] Example 2: In this Example 2, the melting temperature is relatively low (750°C), which helps to reduce energy consumption and lower costs. The aluminum and tin contents are moderate (9% and 2.5%, respectively), while still maintaining good corrosion resistance and dendrite inhibition effects. This embodiment can reduce production energy consumption and costs while maintaining good performance, and is suitable for cost-sensitive application scenarios and magnesium batteries with medium performance requirements.

[0035] Example 3: The aluminum and tin contents in Example 3 are moderate (8% and 2%, respectively), which helps to refine the grains and significantly inhibit dendrite growth. The high-temperature smelting at 800°C ensures uniform alloy composition and forms a stable amorphous structure. This embodiment can significantly inhibit dendrite growth, improve the cycle stability of the anode, increase the magnesium ion transmission efficiency, optimize the electrochemical performance, and is suitable for high-rate charge and discharge scenarios. It has excellent cycle stability and mechanical strength.

[0036] Example 4: In Example 4, the bismuth and indium contents are relatively low (0.5% and 0.5%, respectively), and the electrochemical performance is relatively high while still maintaining good corrosion resistance and mechanical strength. The high-temperature smelting at 800°C ensures uniform alloy composition and forms a stable amorphous structure. This embodiment can reduce the polarization of the anode and enhance the interfacial reaction activity. It is suitable for application scenarios that require a balance between cost and performance, performs well under high-rate charge and discharge conditions, and has good electrochemical performance.

[0037] After comparing the above contents, it can be found that magnesium as a base metal needs to have its content kept within a certain range to ensure that the alloy has good machinability and low density, while not affecting the effects of other elements; an appropriate amount of aluminum can improve the corrosion resistance and mechanical strength of the alloy, but too high will cause the alloy to become brittle; tin can improve electrochemical properties and increase alloy strength, but excessive amounts will increase brittleness; bismuth helps inhibit dendrite growth and improve corrosion resistance, but too much may reduce conductivity and affect mechanical properties; indium can significantly improve electrochemical activity and ion transfer rate, but the cost is high and needs to be controlled within a reasonable range. Therefore, in actual applications, it is necessary to comprehensively consider the content of each component according to specific needs and application scenarios to achieve the best performance balance.

[0038] The assembled symmetrical battery was subjected to a cycle performance test: a charge and discharge cycle test was performed at a rate of 0.5C, and the capacity retention rate and coulombic efficiency during the cycle were recorded. During the test, the battery voltage change was monitored to evaluate the battery's cycle stability and activity. The specific test structure is shown in the following table: Measurement results show that after 300 cycles at 0.5C, the alloy anode that has undergone surface sulfidation treatment has a capacity retention rate of ≥90% and a coulombic efficiency of up to 96.2%, which is far superior to the performance of traditional magnesium anodes. In addition, scanning electron microscopy (SEM) shows that after multiple charge and discharge cycles, the surface of the anode of the present invention remains smooth and there is no obvious sign of dendrite growth. This is in sharp contrast to traditional magnesium metal anodes. Under similar cycling conditions, a large number of obvious dendrites will appear on the surface of traditional anodes. These dendrites will not only pierce the diaphragm, causing internal short circuits in the battery and leading to sudden failure of the battery, but also increase the contact area between the electrode and the electrolyte, accelerate the occurrence of interfacial side reactions, and reduce the coulombic efficiency and cycle stability of the battery. The anode of the present invention uses a specific proportion of magnesium, aluminum, tin, bismuth and indium elements, and through amorphous / nanocrystalline structure design and surface magnesium sulfide nanolayer coating, the anode can effectively inhibit the formation and growth of dendrites during the charge and discharge process, thereby significantly improving the safety and cycle life of the battery.

[0039] The electrolyte used in this application: Mg(TFSI)2 is a common magnesium salt electrolyte, and DME (1,2-dimethoxyethane) is a commonly used organic solvent that can provide good ion conductivity. The Mg(TFSI)2 / DME electrolyte has good ion conductivity and chemical stability and is suitable for magnesium battery testing.

[0040] The present application uses the synergistic effect of the five-element alloy: aluminum and bismuth can effectively inhibit intergranular corrosion, aluminum can improve the corrosion resistance of the alloy, enhance the alloy's oxidation resistance and corrosion resistance, bismuth refines the grains and reduces local current concentration, indium increases the ion transfer rate and reduces the interface impedance, tin can enhance the current output efficiency of the anode material, and the alloy formed with magnesium, aluminum, bismuth and indium can inhibit the rapid dissolution of other metals, slow down the corrosion rate of the anode material, and extend the service life. Through this synergistic effect, the dendrite suppression efficiency is improved by 40%. Compared with traditional magnesium alloy anodes, dendrite growth is significantly reduced, and the cycle stability of the battery is greatly improved.

[0041] The present application has high electrochemical activity: the synergistic effect of the components in the quinary alloy improves the electrochemical activity of the anode, so that it has a higher discharge capacity and more stable cycle performance in magnesium batteries.

[0042] This application has good corrosion resistance: the addition of bismuth and aluminum can effectively inhibit the corrosion of magnesium alloy in the electrolyte, thereby extending the service life of the battery.

[0043] The anode of this application has high performance: it can be used in high-rate charge and discharge scenarios. After 300 charge and discharge cycles at a rate of 0.5 times the rated capacity, the capacity retention rate is greater than or equal to 90%. The coulombic efficiency can reach 96.2% compared to the 30-50% of traditional magnesium anodes, greatly improving energy efficiency.

[0044] The magnesium sulfide nanolayer of the present application has the following advantages: 1. The magnesium sulfide nanolayer can act as a physical barrier, effectively blocking the direct contact between the corrosive ions in the electrolyte and the alloy surface, significantly reducing the interfacial corrosion rate; 2. The magnesium sulfide nanolayer has good ionic conductivity, can reduce the interfacial impedance between the alloy and the electrolyte, and improve the transmission efficiency of magnesium ions at the interface; 3. The magnesium sulfide nanolayer can improve the wettability of the alloy surface, make the electrolyte more evenly distributed on the surface, promote the uniform deposition and dissolution of magnesium ions, and inhibit the formation and growth of dendrites; 4. The magnesium sulfide nanolayer has good bonding force with the alloy matrix, can enhance the mechanical strength and wear resistance of the anode surface, and reduce mechanical loss during charging and discharging; 5. During the cycle process, the magnesium sulfide nanolayer can exist stably without obvious structural changes or peeling, ensuring that the anode maintains excellent electrochemical properties throughout its service life.

[0045] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, from all perspectives, the embodiments should be regarded as illustrative and non-restrictive. The scope of the present invention is defined by the appended claims, not the foregoing description, and it is intended that all variations that come within the meaning and range of equivalents of the claims be included within the present invention. Any reference signs in the claims should not be construed as limiting the claim to which they relate.

[0046] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A high-performance magnesium-aluminum-tin-bismuth-indium alloy anode, characterized by: It includes: A five-element alloy matrix, the five-element alloy matrix consisting of 84-92 wt% magnesium, 5-12 wt% aluminum, 2-3 wt% tin, 0.5-2% bismuth and 0.1-1 wt% indium; A functional layer, which is coated on the surface of the five-element alloy substrate and is used to isolate electrolyte corrosion, reduce interface impedance, and improve magnesium ion transmission efficiency; Among them, the five-element alloy matrix and the functional layer work together to form a magnesium-aluminum-tin-bismuth-indium alloy anode. The magnesium-aluminum-tin-bismuth-indium alloy anode has an amorphous / nanocrystalline structure, and its microstructure is formed by rapid solidification technology to reduce local current concentration and inhibit the formation and growth of dendrites.

2. The high performance magnesium-aluminum-tin-bismuth-indium alloy anode according to claim 1, characterized in that: The functional layer is a magnesium sulfide nanolayer, and the thickness of the magnesium sulfide nanolayer is 50-200 nm.

3. The high performance magnesium-aluminum-tin-bismuth-indium alloy anode according to claim 1, characterized in that: The magnesium-aluminum-tin-bismuth-indium alloy anode has high energy density and long cycle life, can work stably in a magnesium-ion battery, and the functional layer significantly improves the corrosion resistance and interface stability of the anode.

4. The high performance magnesium-aluminum-tin-bismuth-indium alloy anode according to claim 2, characterized in that: The amorphous / nanocrystalline structure of the magnesium-aluminum-tin-bismuth-indium alloy anode can reduce local current concentration and optimize the uniformity of the electrochemical reaction, thereby improving the overall performance of the battery. The functional layer further enhances the chemical stability and interface compatibility of the anode through the action of the magnesium sulfide nanolayer, ensuring the long-term stability of the anode in the battery.

5. A method for preparing a high-performance magnesium-aluminum-tin-bismuth-indium alloy anode, for preparing the high-performance magnesium-aluminum-tin-bismuth-indium alloy anode according to any one of claims 1 to 4, characterized in that: It includes the following steps: S1. Raw material preparation: Weigh the required magnesium, aluminum, tin, bismuth and indium raw materials according to mass percentage and place them in a crucible; S2. Heating and melting: Place the crucible in a vacuum furnace, control the heating rate, and melt at high temperature to ensure uniform alloy composition; S3, cooling and rolling: rapidly water-cooling the magnesium-aluminum-tin-bismuth-indium alloy melted in S2 to form an amorphous alloy ingot, and then rolling the amorphous alloy ingot into an alloy foil with a thickness of 100 μm; S4, chemical dealloying treatment: immersing the alloy foil after rolling in S3 in mixed acid to form a porous structure to increase the surface area and reaction activity; S5, surface functional layer coating: immerse the alloy foil after gold removal in S4 in a sodium sulfide solution for reaction to generate a magnesium sulfide nanolayer to improve corrosion resistance and interface stability; S6. Performance testing: Assemble the alloy foil processed in S5 into a battery, test its electrochemical performance, and verify the high performance of the anode.

6. The method for preparing a high-performance magnesium-aluminum-tin-bismuth-indium alloy anode according to claim 5, characterized in that: In the heating and melting step, the heating rate below 500° C. is 8 to 12° C. / minute, and the heating rate above 500° C. is 3 to 6° C. / minute.

7. The method for preparing a high-performance magnesium-aluminum-tin-bismuth-indium alloy anode according to claim 5, characterized in that: In the cooling and rolling step, the smelted five-element alloy is quickly water-cooled to room temperature and then rolled at a rolling temperature of 100-200° C. to ensure that the thickness of the alloy foil is uniform.

8. The method for preparing a high-performance magnesium-aluminum-tin-bismuth-indium alloy anode according to claim 5, characterized in that: In the chemical dealloying step, the mixed acid used is composed of hydrochloric acid and nitric acid in a volume ratio of 3:

1.

9. The method for preparing a high-performance magnesium-aluminum-tin-bismuth-indium alloy anode according to claim 5, characterized in that: In the surface functional layer covering step, the solution is 0.1M Na2S solution.

10. The method for preparing a high-performance magnesium-aluminum-tin-bismuth-indium alloy anode according to claim 5, characterized in that: In the performance testing step, the alloy foil wrapped with the magnesium sulfide nanolayer is assembled into a symmetrical battery, and 0.5M Mg(TFSI)2 / DME is used as the electrolyte to test the electrochemical performance of the battery.

Images