A wide temperature range high iodine loading positive electrode material and preparation method thereof and zinc-iodine battery

Abstract

The present invention relates to the technical field of electrode materials, and specifically to a wide-temperature-range high-iodine-loaded positive electrode material, a preparation method thereof, and a zinc-iodine battery. Activated carbon and iodine element are mixed and then subjected to a heat treatment to sublime the iodine element and embed it into the activated carbon, thereby obtaining iodine-loaded carbon black I2@CB; gelatin and acetic acid solution are mixed to obtain a gelatin binder solution; iodine-loaded carbon black I2@CB, a conductive agent, and the gelatin binder solution are mixed to obtain an iodine positive electrode slurry; the iodine positive electrode slurry is coated on a stainless steel mesh and dried to obtain a wide-temperature-range high-iodine-loaded positive electrode material. The wide-temperature-range high-iodine-loaded positive electrode material prepared by the present invention effectively suppresses the problems of active iodine dissolution and polyiodide shuttling by utilizing the active functional groups of gelatin in the gelatin binder solution, such as peptide bonds, carboxyl groups, and amino groups, to restrain active iodine and chemically adsorb polyiodides.

Description

Technical Field

[0001] The present invention relates to the technical field of electrode materials, and in particular to a wide-temperature-range high-iodine-loading positive electrode material, a preparation method thereof, and a zinc-iodine battery. Background Art

[0002] Intrinsically safe aqueous batteries are a key area of ​​focus for the development of high-energy-density, high-safety energy storage batteries. Compared to lithium- and sodium-ion batteries, which use organic electrolytes and carry flammability and explosion risks, and rely on imports for 70% of their lithium and cobalt resources, aqueous batteries offer low cost, high safety, environmental friendliness, and ease of operation in air, making them a key area of ​​focus for the development of high-safety energy storage batteries. Aqueous zinc batteries, which utilize a high-capacity metallic zinc anode (820 mAh / g) and are compatible with the operating window of aqueous electrolytes, are a hot topic in aqueous battery research. Traditional zinc-based batteries utilize intercalation-type cathode materials, which have low zinc storage capacity and slow kinetics. This mismatch with the high capacity of the zinc anode prevents the full potential of aqueous zinc batteries. Therefore, the development of novel cathode materials is urgently needed. Halogen electrode reactions generally exhibit fast kinetics due to the solubility of halogens. Zinc-iodine batteries, among others, achieve electrochemical energy storage through a conversion reaction mechanism, bypassing the traditional zinc-ion battery's reliance on ion intercalation and deintercalation, thus avoiding the structural collapse of the cathode material. In addition, iodine's low cost, abundant reserves, multivalent properties and high theoretical specific capacity (211 mAh / g) make zinc-iodine batteries a promising candidate for the next generation of clean and efficient energy storage devices.

[0003] However, zinc-iodine batteries still face serious problems with polyiodide shuttling and unstable zinc anodes, limiting their large-scale application. These issues arise because the iodine cathode undergoes a solid-liquid phase transition during the charge and discharge process. Solid iodine molecules discharge into soluble iodide ions, which react with iodine molecules to form soluble polyiodides. Polyiodides dissolved in the electrolyte diffuse to the zinc anode and react irreversibly with the zinc, causing corrosion of the zinc anode and loss of iodine active substances, limiting their practical application. Summary of the Invention

[0004] To address the shortcomings of the prior art, the present invention provides a wide-temperature-range, high-iodine-loaded cathode material, a preparation method thereof, and a zinc-iodine battery. The present invention heat-treats activated carbon and elemental iodine to produce iodine-loaded carbon black I2@CB. The iodine-loaded carbon black I2@CB, a conductive agent, and a gelatin binder solution containing gelatin and acetic acid are then mixed to produce an iodine cathode slurry. Finally, the iodine cathode slurry is coated and dried to produce a wide-temperature-range, high-iodine-loaded cathode material. The wide-temperature-range, high-iodine-loaded cathode material prepared by the present invention effectively suppresses the problems of active iodine dissolution and polyiodide shuttling by utilizing the active functional groups of gelatin in the gelatin binder solution, such as peptide bonds, carboxyl groups, and amino groups, to bind active iodine and chemically adsorb polyiodides.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] The first object of the present invention is to provide a method for preparing a wide temperature range high iodine loading cathode material, comprising the following steps:

[0007] S1. After mixing activated carbon and iodine, heat treatment is performed to sublime the iodine and embed it into the activated carbon to obtain iodine-loaded carbon black I2@CB. The mass ratio of activated carbon to iodine is 1 to 1.5:1. The greater the porosity of the iodine-loaded carbon black, the more iodine it carries, the larger the proportion of active material in the wide-temperature range and high-iodine-loaded positive electrode material, and the higher the energy density.

[0008] S2. Mix gelatin and acetic acid solution to obtain a gelatin binder solution.

[0009] S3. Mixing iodine-loaded carbon black I2@CB, a conductive agent, and a gelatin binder solution to obtain an iodine positive electrode slurry.

[0010] S4. Coat the iodine positive electrode slurry on a stainless steel mesh and dry it to obtain a positive electrode material with a wide temperature range and high iodine loading.

[0011] Preferably, the conditions for the heat treatment are: heating at 100°C to 140°C for 6h to 8h in a sealed container; within this temperature range, iodine sublimates into vapor and diffuses into the pores of the activated carbon, and then condenses into solid iodine after cooling, thereby achieving iodine loading in the activated carbon; and the sealed container is to prevent iodine from sublimating into vapor and overflowing.

[0012] Preferably, the gelatin binder solution contains gelatin at a mass percentage of 2% to 6% by weight. A gelatin mass percentage exceeding 6% by weight will result in an overly viscous gelatin binder solution, making it difficult to mix evenly after adding the conductive agent and iodine-loaded carbon black I2@CB. A gelatin mass percentage below 2% by weight will result in an overly dilute slurry, resulting in poor slurry adhesion when applied to the current collector. Furthermore, gelatin has low solubility in water, is easily gelled, and exhibits high viscosity. Using acetic acid as a solvent improves the viscosity and processability of wide-temperature, high-iodine-loaded cathode materials. Furthermore, gelatin contains abundant polar functional groups, including peptide bonds, amino groups, and carboxyl groups, which exhibit good wettability with the aqueous electrolyte of zinc-iodine batteries, facilitating the formation of a favorable cathode interface and reducing ion transfer impedance.

[0013] Preferably, the mass ratio of iodine-loaded carbon black I2@CB, conductive agent and gelatin binder solution is 7-8:1.5-2:0.5-1; the conductive agent is evenly mixed with the iodine-loaded carbon black I2@CB and gelatin binder solution to achieve smooth electron transmission, and the binder can provide sufficient adhesion to firmly bond the iodine-loaded carbon black I2@CB, conductive agent and current collector.

[0014] Preferably, the iodine is also ground for 1 to 3 minutes to form a fine powder. The grinding time should not be too long to prevent the iodine from sublimating. The iodine of the present invention is a particle slightly larger than sesame seeds. In order to mix evenly with the activated carbon and accelerate sublimation, it must be ground first.

[0015] Preferably, the conductive agent is selected from Ketjen black or conductive carbon materials.

[0016] Preferably, the drying conditions are: drying at 25°C to 35°C for 1 hour to 2 hours.

[0017] Preferably, the solvent in the acetic acid solution is water, and the mass fraction of acetic acid in the acetic acid solution is 75% to 80%.

[0018] Preferably, the current collector is selected from stainless steel mesh or titanium foil.

[0019] The second object of the present invention is to provide a wide temperature range and high iodine loading positive electrode material prepared by the above preparation method.

[0020] The third object of the present invention is to provide a zinc-iodine battery, which is a button battery or a soft-pack battery, and is composed of the above-mentioned wide temperature range high iodine loading positive electrode material, a separator and a negative electrode material and an electrolyte.

[0021] Preferably, the button battery consists of a button battery shell, a gasket and a shrapnel, a glass fiber separator, a ZnSO4 electrolyte, a wide temperature range high iodine loading positive electrode material and a zinc foil disc negative electrode.

[0022] Preferably, the soft-pack battery is composed of a glass fiber separator, a ZnSO4 electrolyte, a wide temperature range high iodine loading positive electrode material and a zinc foil negative electrode.

[0023] Preferably, the soft pack battery is prepared according to the following steps:

[0024] An aluminum current collector is welded to the wide-temperature range high-iodine-loading positive electrode material, and a copper-plated nickel current collector is welded to the negative electrode. The positive electrode, separator, and negative electrode are stacked in sequence, and an aluminum-plastic film is inserted. One end of the aluminum current collector and the copper-plated nickel current collector is led out, and the electrolyte is poured in and hot-pressed for packaging.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1. The present invention provides a method for preparing a wide-temperature-range, high-iodine-loading cathode material. The method comprises mixing activated carbon and elemental iodine, then heating the mixture to sublime the iodine and embed it into the activated carbon, thereby obtaining iodine-loaded carbon black I2@CB. The mass ratio of activated carbon to elemental iodine is 1 to 1.5:1. Gelatin and an acetic acid solution are then mixed to obtain a gelatin binder solution. The iodine-loaded carbon black I2@CB, a conductive agent, and the gelatin binder solution are then mixed to obtain an iodine cathode slurry. The iodine cathode slurry is then coated onto a stainless steel mesh and dried to obtain a wide-temperature-range, high-iodine-loading cathode material. The wide-temperature-range, high-iodine-loading cathode material prepared by the present invention utilizes the active functional groups of gelatin in the gelatin binder solution, such as peptide bonds, carboxyl groups, and amino groups, to enhance the binding capacity of the wide-temperature-range, high-iodine-loading cathode material for active iodine and its chemical adsorption of polyiodides, thereby effectively suppressing the problems of active iodine dissolution and polyiodide shuttling.

[0027] 2. The wide temperature range high iodine loading positive electrode material provided by the present invention has good performances of high loading capacity, high cycle capacity and long life. Gelatin is used as a binder for the wide temperature range high iodine loading positive electrode material, so that the wide temperature range high iodine loading positive electrode material can operate under a wide temperature range of -10°C to 60°C. Gelatin exhibits effective chemical adsorption characteristics for polyiodides. This mechanism significantly inhibits the shuttle effect, thereby reducing the loss of active substance iodine, directly improving the capacity performance of the wide temperature range high iodine loading positive electrode material and enhancing its cycle stability. In addition, due to its inherent high viscosity, gelatin enables the formation of a thicker wide temperature range high iodine loading positive electrode material layer during the preparation process, which provides a larger loading space for iodine, thereby achieving a higher iodine loading.

[0028] 3. The zinc-iodine battery provided by the present invention has excellent anti-self-discharge ability, high rate performance and long-lasting cycle stability in a wide temperature range. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1This is a comparison chart of the cycle performance of the wide temperature range high iodine loading positive electrode material prepared in Example 1 and the iodine positive electrode material prepared in Comparative Example 1 in zinc-iodine batteries, where a is 25°C, b is 60°C, and c is -10°C.

[0030] Figure 2 This is a cycling performance diagram of the wide temperature range, high iodine loading cathode material prepared in Example 1 at high loading and 2C rate.

[0031] Figure 3 This is a comparison chart of the anti-self-discharge performance of the wide temperature range high iodine loading positive electrode material prepared in Example 1 and the iodine positive electrode material prepared in Ratio 1.

[0032] Figure 4 The adsorption performance diagram of the gelatin binder solution prepared in Example 1 and the PTFE binder prepared in Comparative Example 1 is shown, wherein a is the adsorption performance of the gelatin binder solution prepared in Example 1 and the PTFE binder prepared in Comparative Example 1. 3- adsorption, the illustration is I 3- Color comparison chart before and after solution adsorption; b is the adsorption of I2, and the inset is the color comparison chart before and after I2 solution adsorption.

[0033] Figure 5 The contact angle diagrams of the wide temperature range high iodine loading cathode material prepared in Example 1 and the iodine cathode material prepared in Ratio 1 and the electrolyte, where a is PTFE and b is Gelatin. DETAILED DESCRIPTION

[0034] The following will clearly and completely describe the technical solution of the present invention in conjunction with the data in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0035] It should be noted that the professional terms used in the present invention are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present invention. Unless otherwise specified, the various raw materials, reagents, instruments and equipment used in the following embodiments of the present invention can be purchased on the market or prepared by existing methods. Among them, polytetrafluoroethylene is denoted as PTFE.

[0036] In the existing technology, zinc-iodine batteries face serious problems of multiple iodide shuttling and unstable zinc negative electrodes, which limit the large-scale application of zinc-iodine batteries. Traditional methods focus on improving the electrolyte formula, optimizing the battery structure or developing new additives, but these methods are often difficult to fundamentally solve the problems of active iodine dissolution and multiple iodide shuttling. In recent years, improving the cycle stability and energy density of zinc-iodine batteries by designing high-performance positive electrode materials has become a research hotspot. Among them, using porous carbon materials as iodine carriers and fixing iodine molecules by physical adsorption or chemical bonding can effectively reduce iodine dissolution and shuttling effects. However, simple physical adsorption is not enough to maintain the stability of iodine for a long time, especially under high temperature or long-term cycling conditions.

[0037] To address the above technical deficiencies, the present invention provides a method for preparing a wide-temperature-range, high-iodine-loading cathode material, comprising the following steps: mixing activated carbon and elemental iodine, then heating to sublime the iodine and embed it into the activated carbon, thereby obtaining iodine-loaded carbon black I2@CB; wherein the mass ratio of activated carbon to elemental iodine is 1 to 1.5:1; mixing gelatin and an acetic acid solution to obtain a gelatin binder solution; mixing the iodine-loaded carbon black I2@CB, a conductive agent, and the gelatin binder solution to obtain an iodine cathode slurry; coating the iodine cathode slurry onto a stainless steel mesh, and drying the resulting wide-temperature-range, high-iodine-loading cathode material. The wide-temperature-range, high-iodine-loading cathode material prepared by the present invention effectively suppresses the problems of active iodine dissolution and polyiodide shuttling by utilizing the active functional groups of gelatin in the gelatin binder solution, such as peptide bonds, carboxyl groups, and amino groups, to bind active iodine and chemically adsorb polyiodides.

[0038] The technical solution of the present invention is further explained below using embodiments, which are specifically as follows:

[0039] Example 1

[0040] A method for preparing a wide temperature range high iodine loading cathode material comprises the following steps:

[0041] S1. Activated carbon and iodine were mixed in a mortar at a mass ratio of 1:1, and ground in a mortar for about 2 minutes until fine. The mixture was then taken out and added to a glass sample bottle. The mixture was placed in a forced air drying oven and heated at 120°C for 6 hours to allow the iodine to sublime and embed into the activated carbon, thereby obtaining iodine-loaded carbon black I2@CB.

[0042] S2. Prepare an acetic acid solution according to a mass ratio of acetic acid to water of 8:2, weigh type A gelatin and dissolve it in the acetic acid solution, and then heat it in a water bath at 60°C for 2 hours to obtain a gelatin binder solution, wherein the mass fraction of type A gelatin in the gelatin binder solution is 5wt%.

[0043] S3. Weigh iodine-loaded carbon black I2@CB, Ketjen black and gelatin binder solution respectively, with the mass ratio of iodine-loaded carbon black I2@CB, Ketjen black and gelatin binder solution being 7:2:1, and then put them into a mortar and grind them for 5 minutes. During the process, acetic acid solution is added to adjust the viscosity of the iodine positive electrode slurry, and continue wet grinding for 2 minutes to obtain iodine positive electrode slurry.

[0044] S4. Coat the iodine positive electrode slurry on a stainless steel mesh and place it in an oven to dry at 25°C for 2 hours to obtain a wide temperature range high iodine loading positive electrode material, which is recorded as Gelatin.

[0045] Example 2

[0046] A method for preparing a wide temperature range high iodine loading cathode material comprises the following steps:

[0047] S1. Activated carbon and iodine were mixed in a mass ratio of 1.5:1, added to a mortar and ground for about 2 minutes until fine. The mixture was then removed and added to a glass sample bottle. The mixture was placed in a forced air drying oven and heated at 100°C for 8 hours to allow the iodine to sublime and embed into the activated carbon, thereby obtaining iodine-loaded carbon black I2@CB.

[0048] S2. Prepare an acetic acid solution according to a mass ratio of acetic acid to water of 8:2, weigh type A gelatin and dissolve it in the acetic acid solution, and then heat it in a water bath at 60°C for 2 hours to obtain a gelatin binder solution, wherein the mass fraction of type A gelatin in the gelatin binder solution is 6wt%.

[0049] S3. Weigh iodine-loaded carbon black I2@CB, Ketjen black and gelatin binder solution respectively, with the mass ratio of iodine-loaded carbon black I2@CB, Ketjen black and gelatin binder solution being 7:2:1, and then put them into a mortar and grind them for 5 minutes. During the process, acetic acid solution is added to adjust the viscosity of the iodine positive electrode slurry, and continue wet grinding for 2 minutes to obtain iodine positive electrode slurry.

[0050] S4. Coat the iodine positive electrode slurry on a stainless steel mesh and place it in an oven to dry at 25°C for 2 hours to obtain a positive electrode material with a wide temperature range and high iodine loading.

[0051] Example 3

[0052] A method for preparing a wide temperature range high iodine loading cathode material comprises the following steps:

[0053] S1. Activated carbon and iodine were mixed in a 1:1 mass ratio, added to a mortar and ground for about 2 minutes until fine; then taken out and added to a glass sample bottle, placed in a forced air drying oven and heated at 140°C for 6 hours to allow the iodine to sublime and embed into the activated carbon to obtain iodine-loaded carbon black I2@CB.

[0054] S2. Prepare an acetic acid solution according to a mass ratio of acetic acid to water of 8:2, weigh type A gelatin and dissolve it in the acetic acid solution, and then heat it in a water bath at 60°C for 2 hours to obtain a gelatin binder solution, wherein the mass fraction of type A gelatin in the gelatin binder solution is 2 wt%.

[0055] S3. Weigh iodine-loaded carbon black I2@CB, Ketjen black and gelatin binder solution respectively, with the mass ratio of iodine-loaded carbon black I2@CB, Ketjen black and gelatin binder solution being 8:1.5:0.5. Then put them into a mortar and grind them for 10 minutes. During the process, acetic acid solution is added to adjust the viscosity of the iodine positive electrode slurry, and continue wet grinding for 5 minutes to obtain iodine positive electrode slurry.

[0056] S4. Coat the iodine positive electrode slurry on a stainless steel mesh and place it in an oven to dry at 35°C for 1 hour to obtain a positive electrode material with a wide temperature range and high iodine loading.

[0057] Comparative Example 1

[0058] A method for preparing an iodine-loaded positive electrode material comprises the following steps:

[0059] S1. Activated carbon and iodine were mixed in a mass ratio of 1:1, added to a mortar and ground for about 2 minutes until fine; then taken out and added to a glass sample bottle, placed in a forced air drying oven and heated at 60°C for 6 hours to allow the iodine to sublime and embed into the activated carbon to obtain iodine-loaded carbon black I2@CB.

[0060] S2. Weigh iodine-loaded carbon black I2@CB, Ketjen black, and PTFE binder respectively, with a mass ratio of iodine-loaded carbon black I2@CB, Ketjen black, and PTFE binder being 7:2:1. Then put them into a mortar and grind them for 5 minutes. During the process, water is continuously added to adjust the viscosity of the iodine positive electrode slurry to obtain a positive electrode slurry.

[0061] S3. Coat the positive electrode slurry on a stainless steel mesh and place it in an oven at 25° C. to 35° C. to dry for 2 h to obtain an iodine-loaded positive electrode material, which is recorded as PTFE.

[0062] Application method:

[0063] The wide temperature range high iodine loading positive electrode material prepared in Example 1 and the iodine-loaded positive electrode material prepared in Comparative Example 1 were respectively used as positive electrode sheets and placed in the center of the positive electrode shell. A small amount of 2 mol / L ZnSO4 electrolyte was dropped, and a glass fiber diaphragm was installed. The electrolyte was continued to be added until it was soaked. A zinc foil disc was taken and aligned with the position of the positive electrode sheet and placed in the battery shell. A gasket and a spring were placed, and the battery sealing machine was used to encapsulate them to obtain zinc-iodine button batteries, which were respectively recorded as Gelatin-button battery and PTFE-button battery.

[0064] observe Figure 1The present invention uses gelatin as a functional binder to improve the electrochemical performance of zinc-iodine batteries. Compared to commonly used polytetrafluoroethylene (PTFE) binders, the battery using the gelatin binder solution exhibits higher cycle capacity and longer cycle life, whether tested at room temperature (25°C), high temperature (60°C), or low temperature (-10°C). After 14,000 cycles of charge and discharge at 10C at room temperature, the gelatin-based button cell achieved a specific discharge capacity of 123 mAh / g, while the PTFE-based button cell failed after approximately 9,000 cycles, with a specific discharge capacity of only 96 mAh / g.

[0065] observe Figure 2 It was concluded that type A gelatin, as a binder, can be used to make a high-loaded iodine positive electrode. When the iodine loading is about 10 mg, it can still stably cycle nearly 700 times under 2C conditions, and the specific capacity remains at 124 mAh / g.

[0066] observe Figure 3 It was concluded that gelatin binder solution also has advantages in resisting self-discharge. After the zinc-iodine button battery was charged to 1.6V and then left to stand for 48 hours, the voltage of the PTFE-button battery dropped to 1.268V, while the Gelatin-button battery still maintained 1.315V, indicating that the Gelatin-button battery has strong resistance to self-discharge.

[0067] Adsorption test:

[0068] The gelatin adhesive solution prepared in Example 1 was dripped onto a glass sheet and dried to obtain a gelatin adhesive film. 3- Weigh equal mass of PTFE binder powder and add I 3- After 30 minutes of rest, the color change of the solution was observed, and the I3 in the solution was quantitatively characterized by UV-visible spectroscopy. - Among them, I3 - It is formed by the reaction of 8mmol / L I2 and 8mmol / L KI dissolved in water, and its concentration is 8mmol / L.

[0069] observe Figure 4 The illustration of Figure a in the figure shows that in the brown I 3- After the gelatin binder solution prepared in Example 1 was added to the solution for adsorption, the brown-yellow 3- The color of the solution becomes lighter, and the Figure 4 The UV-visible absorption spectrum results in Figure a show that the gelatin binder solution can reduce I 3- The aggregation density is related to I 3-It has a strong chemical adsorption effect, weakening its diffusion to the negative electrode and inhibiting the shuttle effect. It adsorbs I2 and reduces the dissolution of active iodine. Observe Figure 4b. After adding the gelatin binder solution prepared in Example 1 to the I2 solution, the color of the I2 solution gradually becomes clear, indicating that the concentration of I2 in the I2 solution is significantly reduced.

[0070] Depend on Figure 5 Draw, observe Figure 5 As shown in Figure a, the contact angle of the PTFE binder is 41°, while the abundant polar functional groups in type A gelatin, such as peptide bonds, amino groups, and carboxyl groups, make the wide temperature range high iodine loading cathode material have good affinity with the electrolyte, and the contact angle is 0, as shown in Figure 5. Figure 5 As shown in Figure b, it can reduce the impedance at the interface and improve the performance of zinc-iodine button batteries.

[0071] It should be noted that when numerical ranges are mentioned in the present invention, it should be understood that both endpoints of each numerical range and any value between the two endpoints may be selected. Since the steps and methods used are the same as those in the embodiments, in order to avoid redundancy, the present invention describes preferred embodiments. Although preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they understand the basic inventive concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0072] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A method for preparing a wide temperature range high iodine loading cathode material, characterized in that: The following steps are involved: After mixing activated carbon and iodine, the mixture is heated to allow the iodine to sublime and embed into the activated carbon, thereby obtaining iodine-loaded carbon black I2@CB; wherein the mass ratio of activated carbon to iodine is 1-1.5:1; After mixing gelatin and acetic acid solution, a gelatin binder solution is obtained; The iodine-loaded carbon black I2@CB, a conductive agent, and a gelatin binder solution are mixed to obtain an iodine positive electrode slurry; The iodine positive electrode slurry is coated on the current collector and dried to obtain a wide temperature range high iodine loading positive electrode material; In the gelatin binder solution, the mass percentage of gelatin is 2wt%~6wt%; The solvent in the acetic acid solution is water, and the mass fraction of acetic acid in the acetic acid solution is 75%~80%.

2. The method for preparing a wide temperature range high iodine loading cathode material according to claim 1, characterized in that: The heat treatment conditions are: heating at 100°C~140°C in a sealed container for 6h~8h.

3. The method for preparing a wide temperature range high iodine loading cathode material according to claim 1, characterized in that: The mass ratio of iodine-loaded carbon black I2@CB, conductive agent and gelatin binder solution is 7~8:1.5~2:0.5~1.

4. A wide temperature range high iodine loading positive electrode material obtained by the preparation method of the wide temperature range high iodine loading positive electrode material according to any one of claims 1 to 3.

5. A zinc-iodine battery, characterized in that: The zinc-iodine battery is a button battery or a soft-pack battery, and is composed of the wide-temperature range high-iodine-loading positive electrode material according to claim 4, a separator, a negative electrode material and an electrolyte.

6. The zinc-iodine battery according to claim 5, characterized in that: The button battery consists of a button battery shell, a gasket, a shrapnel, a glass fiber separator, a ZnSO4 electrolyte, a wide temperature range high iodine loading positive electrode material and a zinc foil disc negative electrode.

7. The zinc-iodine battery according to claim 5, characterized in that: The soft-pack battery consists of a glass fiber separator, a ZnSO4 electrolyte, a wide-temperature range high-iodine-loading positive electrode material, and a zinc foil negative electrode.

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