Water-based zinc-iodine battery with high magnification and ultra-long cycle life and preparation method of water-based zinc-iodine battery

Abstract

The invention relates to the technical field of aqueous secondary batteries, in particular to an aqueous zinc-iodine battery with high magnification and ultra-long cycle life and a preparation method thereof, the aqueous zinc-iodine battery mainly comprises a zinc-containing negative electrode, an iodine-containing positive electrode and an organic-water hybrid electrolyte; the organic-water hybrid electrolyte mainly comprises a zinc salt and methyl acetoacetate. According to the invention, the iodine-containing positive electrode is matched with the zinc-containing negative electrode, the zinc salt and methyl acetoacetate, and polyiodide ions preferentially react with C atoms in acetyl, so that triiodide ions in a polyiodide polymer generated by the aqueous zinc-iodine battery chemically react with acetyl; a shuttling effect caused by a reaction of a multi-iodine polymer generated by an aqueous zinc-iodine battery and zinc is avoided; moreover, the reversible chemical reaction of acetyl and iodine is utilized, and methyl acetoacetate can participate in the solvation structure of Zn < 2 + >, so that the aqueous zinc-iodine battery has the characteristics of high capacity, fast dynamics, long cycle life and the like.

Description

Technical Field

[0001] The invention relates to the technical field of aqueous secondary batteries, and in particular to an aqueous zinc-iodine battery with a high rate and ultra-long cycle life and a preparation method thereof. Background Art

[0002] Currently, lithium-ion batteries are widely used in electric vehicles, aviation crafts and portable electronic products, and they have occupied most of the market; however, the scarcity and high cost of lithium resources, as well as flammable and toxic organic electrolytes, have greatly hindered their application. Therefore, there is an urgent need to develop safe, reliable and low-cost alternatives to meet the needs of rail transportation and next-generation electronic devices.

[0003] Aqueous zinc-ion batteries have high theoretical specific capacity, abundant zinc reserves, and good stability in air, and are considered to be one of the most promising candidate batteries in the past few decades. 2+ Different from the insertion and extraction of ions, aqueous zinc-iodine (Zn / / I2) batteries store energy based on the redox reaction of iodine at the cathode and the deposition / stripping of zinc at the anode. In recent years, Zn / / I2 batteries have made great progress in the development of cathode materials with high specific capacity and long service life, mainly focusing on various carbon materials, single-atom materials, coordination materials, and conductive polymers. In terms of zinc anodes, the main focus is on inhibiting dendrite growth and inhibiting the generation of by-products. In terms of electrolytes, the main focus is on regulating additives and modifying the diaphragm. However, Zn / / I2 batteries currently still face problems such as slow reaction kinetics, multi-iodine shuttle effect, low energy density, and instability of the zinc anode.

[0004] Therefore, the prior art still needs to be improved and developed. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide an aqueous zinc-iodine battery with a high rate and ultra-long cycle life and a preparation method thereof, aiming to solve the problems of slow reaction kinetics, multi-iodine shuttle effect and low energy density in the existing zinc-iodine batteries.

[0006] The technical solution of the present invention is as follows:

[0007] A high-rate and ultra-long cycle life aqueous zinc-iodine battery mainly consists of a zinc-containing negative electrode, an iodine-containing positive electrode and an organic-aqueous hybrid electrolyte; the organic-aqueous hybrid electrolyte mainly includes zinc salt and methyl acetoacetate.

[0008] In the high-rate and ultra-long cycle life aqueous zinc-iodine battery, the organic-water hybrid electrolyte also includes deionized water, and the volume of the methyl acetoacetate accounts for 18%-25% of the total volume of the deionized water and the methyl acetoacetate.

[0009] The aqueous zinc-iodine battery with high rate and ultra-long cycle life, wherein the concentration of the zinc salt in the organic-water hybrid electrolyte is 1 mol·L -1 ~2mol·L -1 .

[0010] The high-rate and ultra-long cycle life aqueous zinc-iodine battery, wherein the zinc salt comprises one or more of zinc trifluoromethanesulfonate, zinc sulfate, and zinc chloride.

[0011] The high-rate and ultra-long cycle life aqueous zinc-iodine battery, wherein the iodine-containing positive electrode comprises one of an activated carbon adsorbed zinc iodide positive electrode, an activated carbon adsorbed elemental iodine positive electrode, an iodine-loaded carbon cloth electrode piece, and a zinc iodide-loaded carbon cloth electrode piece.

[0012] The aqueous zinc-iodine battery with high rate and ultra-long cycle life, wherein the iodine loading in the iodine-containing positive electrode is greater than 4 mg / cm 2 .

[0013] The high-rate and ultra-long cycle life aqueous zinc-iodine battery, wherein the zinc-containing negative electrode is a zinc foil or a flexible conductive substrate loaded with a zinc-containing active layer.

[0014] The high-rate and ultra-long cycle life aqueous zinc-iodine battery, wherein the zinc-containing active layer is mainly composed of an active material, a conductive agent and a binder; the active material includes one or more of zinc powder and zinc oxide powder; the conductive agent includes one or more of graphite, acetylene black, Ketjen black, carbon fiber, and carbon nanotubes; the binder includes one or more of PVDF, PTFE, and CMC.

[0015] The aqueous zinc-iodine battery with high rate and ultra-long cycle life, wherein the flexible conductive substrate comprises one of copper, stainless steel, titanium, graphite paper, zinc, silver, carbon cloth, and carbon nanofiber paper.

[0016] A method for preparing a high-rate and ultra-long cycle life aqueous zinc-iodine battery comprises the following steps:

[0017] Applying the positive electrode slurry on the current collector to obtain a positive electrode sheet;

[0018] The positive electrode sheet is immersed in a zinc iodide aqueous solution and dried to obtain an iodine-containing positive electrode;

[0019] mixing the zinc salt aqueous solution with methyl acetoacetate to obtain an electrolyte;

[0020] The iodine-containing positive electrode, the electrolyte and the zinc-containing negative electrode are assembled to obtain an aqueous zinc-iodine battery.

[0021] Beneficial effects: The present invention provides an aqueous zinc-iodine battery with a high rate and ultra-long cycle life and a preparation method thereof. The aqueous zinc-iodine battery with a high rate and ultra-long cycle life is mainly composed of a zinc-containing negative electrode, an iodine-containing positive electrode and an organic-water hybrid electrolyte; the organic-water hybrid electrolyte mainly includes zinc salt and methyl acetoacetate. The present invention uses an iodine-containing positive electrode to match a zinc-containing negative electrode and zinc salts with methyl acetoacetate. Since the electropositivity of the carbon atom in the acetyl group is much stronger than the carbon positivity in the ester group, the polyiodide ions react preferentially with the C atoms in the acetyl group, thereby causing the triiodide ions in the polyiodine polymer generated by the aqueous zinc-iodine battery to react chemically with the acetyl group, so that a portion of the polyiodine polymer is reacted, thereby avoiding the "shuttle effect" caused by the reaction of the polyiodine polymer generated by the aqueous zinc-iodine battery with zinc; and, by utilizing the reversible chemical reaction of the acetyl group and iodine, and methyl acetoacetate can participate in the Zn 2+ The solvation structure makes the aqueous zinc-iodine battery have the characteristics of high capacity, fast kinetics and long cycle life. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The infrared spectra of Example 1 of the present invention with different proportions of methyl acetoacetate added;

[0023] Figure 2 The cyclic voltammogram of the aqueous zinc-iodine battery assembled in Example 1 of the present invention at a scan rate of 1-5 mV / s;

[0024] Figure 3 The figure is a rate charge and discharge curve diagram of the aqueous zinc-iodine battery assembled in Example 1 of the present invention;

[0025] Figure 4 The aqueous zinc-iodine battery assembled in Example 1 of the present invention was tested in air, 60Ag -1 Charge and discharge curves under current density;

[0026] Figure 5 The aqueous zinc-iodine battery assembled in Example 1 of the present invention was tested in air, 60Ag -1 Cycling performance diagram at different current densities. DETAILED DESCRIPTION

[0027] The present invention provides a high-rate ultra-long cycle life aqueous zinc-iodine battery and a preparation method thereof. To make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0028] It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as generally understood by those skilled in the art in the art to which the present invention belongs. It should also be understood that terms such as those defined in general dictionaries should be understood to have meanings consistent with the meanings in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless specifically defined as herein.

[0029] In aqueous electrolytes, Zn / / I2 batteries exhibit reversible I - / I2 / I 3- Redox reaction in which polyiodides serve as intermediates. However, the highly soluble polyiodide intermediates induce a severe shuttle effect, resulting in irreversible loss of active materials, leading to slow kinetics of Zn-I2 batteries. Worse still, the direct reaction between polyiodides with the shuttle effect and the zinc anode further exacerbates severe zinc corrosion and consumption, leading to low coulombic efficiency and limited durability of Zn / / I2 batteries. Therefore, improving the kinetics, cycle life, and coulombic efficiency of Zn / / I2 batteries is of great significance for the development of Zn / / I2 batteries.

[0030] Based on this, the present invention provides an aqueous zinc-iodine battery with a high rate and ultra-long cycle life, which is mainly composed of a zinc-containing negative electrode, an iodine-containing positive electrode and an organic-aqueous hybrid electrolyte; the organic-aqueous hybrid electrolyte mainly includes zinc salt and methyl acetoacetate.

[0031] In this embodiment, an iodine-containing positive electrode is matched with a zinc-containing negative electrode and a zinc salt and methyl acetoacetate (MA). Since the electropositivity of the carbon atom in the acetyl group is much stronger than the carbon positivity in the ester group, the polyiodide ions react with the C atom in the acetyl group first, thereby causing the triiodide ions in the polyiodine polymer generated by the aqueous zinc-iodine battery to react chemically with the acetyl group, so that a portion of the polyiodine polymer is reacted, thereby avoiding the "shuttle effect" caused by the reaction of the polyiodine polymer generated by the aqueous zinc-iodine battery with zinc; and, by utilizing the reversible chemical reaction of the acetyl group and iodine, and the fact that methyl acetoacetate can participate in the Zn 2+ The solvation structure of the aqueous zinc-iodine battery makes the aqueous zinc-iodine battery have the characteristics of high capacity, fast kinetics and long cycle life. In addition, the aqueous zinc-iodine battery with high rate and ultra-long cycle life realizes two charging and discharging platforms, corresponding to I - / I 3- and I 3- / I2 redox reaction. In addition, the acetyl group in the additive can undergo a reversible redox reaction with iodine. This redox reaction can enable the aqueous zinc-iodine battery to have the advantages of high rate performance and long cycle stability.

[0032] Specifically, compared with the previous zinc-iodine battery, the use of zinc salt and methyl acetoacetate as the main components of the electrolyte can effectively simplify the battery structure, so that it can be combined with the process means of producing large batteries, providing the possibility of manufacturing commercial zinc-iodine batteries. The electrolyte is applied to the aqueous zinc-iodine battery, so that the whole battery has faster reaction kinetics. This method is simple, easy to prepare, low-cost, and suitable for large-scale production. At the same time, the assembled aqueous zinc-iodine secondary battery has excellent electrochemical properties. In addition, the present invention rationally designs the zinc-iodine battery, and realizes that the zinc-iodine full battery has faster reaction kinetics by introducing a high proportion of organic solvents. This method is simple, easy to operate, and efficient, and the cost of the electrolyte containing organic and water hybrids is relatively low, which meets the industrial production and commercial application requirements of aqueous zinc-iodine batteries.

[0033] In some embodiments, the organic-water hybrid electrolyte further includes deionized water, and the volume of the methyl acetoacetate accounts for 18%-25% of the total volume of the deionized water and the methyl acetoacetate. The addition of a large amount of organic solvent will participate in the Zn 2+ On the other hand, the solvation structure will improve the reaction kinetics of the battery.

[0034] In a preferred embodiment, the organic-aqueous hybrid electrolyte also includes deionized water, and the volume of the methyl acetoacetate accounts for 20% of the total volume of the deionized water and the methyl acetoacetate. The methyl acetoacetate organic solvent in this volume ratio can accelerate the reaction kinetics of the zinc-iodine battery, consume a portion of the polyiodide to allow the reaction to proceed as quickly as possible, and achieve a charge and discharge reaction with high reversibility.

[0035] In some embodiments, the concentration of the zinc salt in the organic-aqueous hybrid electrolyte is 1 mol·L -1 ~2mol·L -1 If the zinc salt concentration is too high, it will lead to high viscosity and high cost problems. On the one hand, if the zinc salt concentration is too high, high viscosity will slow down the migration rate of ions; on the other hand, if the zinc salt concentration is too high, the cost of zinc salt will increase.

[0036] In a preferred embodiment, the concentration of the zinc salt in the organic-water hybrid electrolyte is 1.5 mol·L -1 In this way, the system contains an appropriate proportion of water, which will not cause excessive costs on the one hand, and on the other hand, the mobility of ions in the solution system will not be slowed down.

[0037] In some embodiments, the zinc salt includes one or more of zinc trifluoromethanesulfonate, zinc sulfate, and zinc chloride. The provision of zinc salt can provide sufficient Zn 2+ , which can make the redox reaction proceed smoothly.

[0038] In a preferred embodiment, the organic-water hybrid electrolyte mainly includes zinc trifluoromethanesulfonate and methyl acetoacetate, and the reversible chemical reaction of acetyl and iodine and methyl acetoacetate can participate in the reaction of Zn 2+ The solvation structure makes the aqueous zinc-iodine battery have the characteristics of high capacity, fast kinetics and long cycle life.

[0039] In some embodiments, the iodine-containing positive electrode includes one of an activated carbon adsorbed zinc iodide positive electrode, an activated carbon adsorbed elemental iodine positive electrode, an iodine-loaded carbon cloth electrode piece, and a zinc iodide-loaded carbon cloth electrode piece. Providing iodine in the form of adsorption or loading can increase its reaction contact specific surface area and improve the reaction kinetics of the battery.

[0040] In some embodiments, the iodine loading in the iodine-containing positive electrode is greater than 4 mg / cm 2 The iodine loading is controlled within this range so that a portion of the formed polyiodine polymer is reacted, thus avoiding the "shuttle effect" caused by the reaction between the polyiodine polymer generated by the aqueous zinc-iodine battery and zinc.

[0041] In some embodiments, the zinc-containing negative electrode is a zinc foil or a flexible conductive substrate loaded with a zinc-containing active layer. 2+ The solvation structure results in the aqueous zinc-iodine battery having the characteristics of high capacity, fast kinetics and long cycle life.

[0042] In some embodiments, the zinc-containing active layer is mainly composed of an active material, a conductive agent and a binder; the active material includes one or more of zinc powder and zinc oxide powder; the conductive agent includes one or more of graphite, acetylene black, Ketjen black, carbon fiber, and carbon nanotubes; the binder includes one or more of PVDF, PTFE, and CMC.

[0043] In some embodiments, the flexible conductive substrate includes one of copper, stainless steel, titanium, graphite paper, zinc, silver, carbon cloth, and carbon nanofiber paper, and the flexible conductive substrate has good conductivity.

[0044] In addition, the present invention also provides a method for preparing a high-rate and ultra-long cycle life aqueous zinc-iodine battery, comprising the steps of:

[0045] Step S10: coating the positive electrode slurry on the current collector to obtain a positive electrode sheet;

[0046] Step S20: soaking the positive electrode sheet in a zinc iodide aqueous solution and drying to obtain an iodine-containing positive electrode;

[0047] Step S30: mixing the zinc salt aqueous solution with methyl acetoacetate to obtain an electrolyte;

[0048] Step S40: Assembling the iodine-containing positive electrode, the electrolyte and the zinc-containing negative electrode to obtain an aqueous zinc-iodine battery.

[0049] In this embodiment, an organic and aqueous hybrid electrolyte is used to change the reaction mechanism of the zinc-iodine battery, simplify the structure and improve the reversibility; an iodine-containing positive electrode is matched with a zinc-containing negative electrode and zinc salts and methyl acetoacetate (MA); since the electropositivity of the carbon atom in the acetyl group is much stronger than the carbon positivity in the ester group, the polyiodide ions react preferentially with the C atom in the acetyl group, thereby causing the triiodide ions in the polyiodine polymer generated by the aqueous zinc-iodine battery to react chemically with the acetyl group, so that a portion of the polyiodine polymer is reacted, thereby avoiding the "shuttle effect" caused by the reaction of the polyiodine polymer generated by the aqueous zinc-iodine battery with zinc; and, by utilizing the reversible chemical reaction of the acetyl group and iodine, and the fact that methyl acetoacetate can participate in the Zn 2+ The solvation structure makes the aqueous zinc-iodine battery have the characteristics of high capacity, fast kinetics and long cycle life.

[0050] In some embodiments, the step S10 specifically includes: cutting the carbon cloth into a suitable size and placing it in a high-pressure hydrothermal autoclave containing concentrated nitric acid for hydrothermal treatment. After cooling to room temperature, the carbon cloth is taken out, ultrasonically treated with deionized water, then rinsed with deionized water and ethanol and vacuum dried to obtain a carbon current collector; then, activated carbon, Ketjen black, and PVDF are placed in a beaker in proportion, and appropriate N-methylpyrrolidone (NMP) is added for sufficient stirring, and then coated on the treated carbon cloth after stirring, and after vacuum drying, cut into a circular electrode with a diameter of 7 cm to obtain a positive electrode.

[0051] In some embodiments, the temperature of the hydrothermal treatment is 100° C.-130° C., and the time of the hydrothermal treatment is 7 h-9 h.

[0052] In some embodiments, the mass ratio of the activated carbon, the Ketjen black and the PVDF is (6-7):(2-3):1.

[0053] In some embodiments, the zinc-containing negative electrode is pure zinc foil with a thickness of 90 mm-120 mm.

[0054] The following examples are further given to illustrate the present invention in detail. It should also be understood that the following examples are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the above content of the present invention belong to the scope of protection of the present invention.

[0055] Example 1

[0056] This embodiment provides an aqueous zinc-iodine battery with a high rate and ultra-long cycle life, and the specific preparation steps are as follows:

[0057] Preparation of carbon cloth loaded with iodine positive electrode: First, the carbon cloth was cut into appropriate sizes and placed in a high-pressure hydrothermal autoclave containing concentrated nitric acid for hydrothermal treatment at 120°C for 8 hours. After cooling to room temperature, the carbon cloth was taken out, ultrasonically treated with deionized water, then rinsed with deionized water and ethanol, and vacuum dried at 80°C to obtain a carbon current collector.

[0058] Then, put the activated carbon: Ketjen black: PVDF in a mass ratio of 7:2:1 into a beaker, add appropriate N-methylpyrrolidone (NMP) and stir thoroughly, and then coat it on the treated carbon cloth after stirring for 12 hours, and vacuum dry it at 60°C for 12 hours. Cut the dried carbon cloth into a circular electrode with a diameter of 7 cm.

[0059] Finally, prepare a 2 mol / L or less than 2 mol / L zinc iodide aqueous solution, soak the above-cut electrode coated with slurry in the zinc iodide aqueous solution for half an hour, take out the soaked electrode and dry it at 40°C under vacuum for 12 hours to obtain a carbon cloth-loaded iodine positive electrode.

[0060] Preparation of methyl acetoacetate electrolyte: First, prepare a 1M aqueous solution of zinc trifluoromethanesulfonate (Zn(OTF)2), then add methyl acetoacetate (MA) organic solvent in different volume ratios (5%, 10%, 15%, 20%) to the solution, and mix the two solutions thoroughly. Figure 1 The infrared spectra of the samples with different proportions of additives (methyl acetoacetate) are shown in Figure 1. Figure 1 It can be seen that the -OH in water has undergone an obvious blue shift, indicating that the introduction of MA can significantly weaken the strong hydrogen bonding interaction of water.

[0061] Preparation of aqueous zinc-iodine battery: An aqueous zinc-iodine battery was prepared using iodine supported on carbon cloth as the positive electrode, pure zinc foil as the negative electrode (100 mm thick), and methyl acetoacetate electrolyte as the electrolyte. Figure 2 This is the cyclic voltammogram of the aqueous zinc-iodine battery at a scan rate of 1-5mV / s. From the figure, we can see that the reaction consists of two pairs of redox peaks, corresponding to the two redox platforms in the charge-discharge curve; Figure 3 This is the rate charge and discharge curve of the aqueous zinc-iodine battery in air. From the charge and discharge rate curve, it can be clearly seen that the battery has excellent rate performance under both high current density and low current density, proving that the battery has faster kinetics. The aqueous zinc-iodine battery has a high rate performance at 60Ag. -1 At the current density, the charge and discharge curves tested in air are as follows Figure 4 As shown, the two charging and discharging platforms indicate the existence of two-step I - / I2 / I 3- Furthermore, the aqueous zinc-iodine battery was tested in air, and 60Ag -1 The long cycle performance under current density is shown in the figure Figure 5 As shown in the figure, it can be clearly seen that the battery is -1 At a current density of 1.5 %, the initial capacity can reach 80 mAh g -1 After 30,000 cycles, the capacity is still about 78 mAh g -1 , has good reversibility.

[0062] In summary, the present invention provides an aqueous zinc-iodine battery with a high rate and ultra-long cycle life and a preparation method thereof. The aqueous zinc-iodine battery with a high rate and ultra-long cycle life is mainly composed of a zinc-containing negative electrode, an iodine-containing positive electrode and an organic-water hybrid electrolyte; the organic-water hybrid electrolyte mainly includes zinc salt and methyl acetoacetate. The present invention uses an iodine-containing positive electrode to match a zinc-containing negative electrode and zinc salts with methyl acetoacetate. Since the electropositivity of the carbon atom in the acetyl group is much stronger than the carbon positivity in the ester group, the polyiodide ions react preferentially with the C atoms in the acetyl group, thereby causing the triiodide ions in the polyiodine polymer generated by the aqueous zinc-iodine battery to react chemically with the acetyl group, so that a portion of the polyiodine polymer is reacted, thereby avoiding the "shuttle effect" caused by the reaction of the polyiodine polymer generated by the aqueous zinc-iodine battery with zinc; and, by utilizing the reversible chemical reaction of the acetyl group and iodine, and methyl acetoacetate can participate in the Zn 2+ The solvation structure makes the aqueous zinc-iodine battery have the characteristics of high capacity, fast kinetics and long cycle life.

[0063] It should be understood that the application of the present invention is not limited to the above examples. For ordinary technicians in this field, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A high-rate and ultra-long cycle life aqueous zinc-iodine battery, characterized in that: The invention mainly consists of a zinc-containing negative electrode, an iodine-containing positive electrode and an organic-water hybrid electrolyte; the organic-water hybrid electrolyte mainly comprises zinc salt and methyl acetoacetate.

2. The aqueous zinc-iodine battery with a high rate and ultra-long cycle life according to claim 1, characterized in that: The organic-water hybrid electrolyte also includes deionized water, and the volume of the methyl acetoacetate accounts for 18%-25% of the total volume of the deionized water and the methyl acetoacetate.

3. The aqueous zinc-iodine battery with a high rate and ultra-long cycle life according to claim 1, characterized in that: The concentration of the zinc salt in the organic-water hybrid electrolyte is 1 mol·L -1 ~2mol·L -1 .

4. The aqueous zinc-iodine battery with a high rate and ultra-long cycle life according to claim 1, characterized in that: The zinc salt includes one or more of zinc trifluoromethanesulfonate, zinc sulfate, and zinc chloride.

5. The aqueous zinc-iodine battery with a high rate and ultra-long cycle life according to claim 1, characterized in that: The iodine-containing positive electrode includes one of an activated carbon-adsorbed zinc iodide positive electrode, an activated carbon-adsorbed elemental iodine positive electrode, an iodine-loaded carbon cloth electrode piece, and a zinc iodide-loaded carbon cloth electrode piece.

6. The aqueous zinc-iodine battery with a high rate and ultra-long cycle life according to claim 1, characterized in that: The iodine loading in the iodine-containing positive electrode is greater than 4 mg / cm 2 .

7. The aqueous zinc-iodine battery with a high rate and ultra-long cycle life according to claim 1, characterized in that: The zinc-containing negative electrode is a zinc foil or a flexible conductive substrate loaded with a zinc-containing active layer.

8. The aqueous zinc-iodine battery with a high rate and ultra-long cycle life according to claim 7, characterized in that: The zinc-containing active layer is mainly composed of an active material, a conductive agent and a binder; the active material includes one or more of zinc powder and zinc oxide powder; the conductive agent includes one or more of graphite, acetylene black, Ketjen black, carbon fiber, and carbon nanotubes; the binder includes one or more of PVDF, PTFE, and CMC.

9. The aqueous zinc-iodine battery with a high rate and ultra-long cycle life according to claim 7, characterized in that: The flexible conductive substrate includes one of copper, stainless steel, titanium, graphite paper, zinc, silver, carbon cloth, and carbon nanofiber paper.

10. A method for preparing a high-rate and ultra-long cycle life aqueous zinc-iodine battery according to any one of claims 1 to 9, characterized in that: Includes steps: Applying the positive electrode slurry on the current collector to obtain a positive electrode sheet; The positive electrode sheet is immersed in a zinc iodide aqueous solution and dried to obtain an iodine-containing positive electrode; Mixing the zinc salt aqueous solution with methyl acetoacetate to obtain an electrolyte; The iodine-containing positive electrode, the electrolyte and the zinc-containing negative electrode are assembled to obtain an aqueous zinc-iodine battery.

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