A zinc-iodine battery synergistically stabilized by an inorganic / organic hybrid material and its application

Abstract

The present invention discloses a zinc-iodine battery synergistically stabilized by an inorganic / organic hybrid material and its application, belonging to the technical field of chemical energy batteries. The zinc-iodine battery includes a positive electrode sheet, a negative electrode sheet and an electrolyte; the positive electrode sheet contains an inorganic / organic hybrid material composed of a layered inorganic material and a cyclic two-dimensional organic material. The layered inorganic material and the cyclic two-dimensional organic material are fully mixed to obtain an inorganic / organic hybrid material; the inorganic / organic hybrid material, conductive carbon and binder are ground and mixed, coated on a current collector and then an I- active substance solution is dropped to obtain a positive electrode sheet. The layered inorganic material is zirconium hydrogen phosphate; the cyclic two-dimensional organic material is phthalocyanine. The present invention prepares an inorganic-organic hybrid interface layer, combines the high strength and high modulus of ZPO with the flexibility of PC, significantly improves the phase interface fusion of ZPO / PC, inhibits the shuttle of water-soluble intermediates, and improves the cycle stability and service life of the battery.

Description

Technical Field

[0001] The present invention relates to the technical field of chemical energy batteries, and particularly relates to a zinc-iodine battery synergistically stabilized by an inorganic / organic hybrid material and its application. Background Art

[0002] In order to meet the growing demands of people for portable electronic products and electric vehicles, the development of new electrochemical energy storage systems is of great significance. Compared with organic electrolyte batteries, aqueous rechargeable energy storage devices have higher operating safety and lower costs, and have received increasing attention. Among them, aqueous zinc-iodine batteries have high theoretical capacity, low redox potential, stable chemical properties and rich resources, and have good application prospects. As a multi-valent electrode material, the iodine electrode is rich in sources and has a large capacity (422 mAh g -1 , based on I - —I + ). However, in an aqueous electrolyte, an iodonium ion (I + ) intermediate is formed during the charging process. It has certain oxidizing properties and is prone to hydrolysis in water, resulting in a low Coulombic efficiency. During the discharging process, the shuttle effect of water-soluble intermediates (I - , I 3 - , I 5 - ) will lead to the loss of active species, ultimately resulting in capacity decay and short cycle life, restricting the further development of zinc-iodine batteries.

[0003] Currently, researchers have developed high-concentration electrolytes and eutectic electrolytes to stabilize I + , reduce the occurrence of side reactions. At the same time, these electrolytes have relatively high viscosities, which can inhibit the shuttle of water-soluble intermediates (I - , I 3 - , I 5 - ). However, these electrolytes have high costs, are prone to freezing at low temperatures and have high viscosities, ultimately resulting in sluggish reaction kinetics and poor electrochemical performance of zinc-iodine batteries. Therefore, in addition to improving the electrolyte, the positive and negative electrodes can also be improved. For example, designing more excellent cathode materials can effectively capture and stabilize these intermediates (I - , I 3 - , I 5 -), thus avoiding the shuttle effect of the intermediate in the electrolyte. If a two-dimensional layer structure is added to the positive electrode, the contact area with the electrolyte can be increased, the ion diffusion path can be shortened, and the kinetic performance can be improved. The layered material has a periodic layered structure and a two-dimensional ion transport channel, thereby improving the ion transport rate; the layered material has strong structural stability and can maintain its integrity well during charge and discharge, without significant volume change or structural collapse, thus providing a stable environment for the continuous transport of ions.

[0004] When it comes to two-dimensional layered materials, the most easily thought of ones currently are inorganic materials such as graphene, boron nitride, and MoS 2 etc. In particular, there are many reports on the use of graphene as an electrode material. However, graphene has low strength and few active sites, and it is difficult to inhibit the shuttle of water-soluble intermediates (I - 、I 3 - 、I 5 - ) only by graphene. Therefore, it is necessary to develop more positive electrode materials containing layered structures for preparing more stable zinc-iodine batteries, reducing the hindrance suffered by ions when moving between layers in the aqueous electrolyte, inhibiting the shuttle ability of water-soluble intermediates, and improving the cycle stability and service life of the battery. Summary of the Invention

[0005] Aiming at the above-mentioned prior art, the purpose of the present invention is to provide a zinc-iodine battery stabilized by inorganic / organic hybrid materials and its application. The present invention fully mixes the inorganic layered material zirconium hydrogen phosphate (ZPO) and the cyclic two-dimensional organic material phthalocyanine (PC) to form an inorganic-organic hybrid interface layer to make a positive electrode sheet, and combines the high strength and high modulus of ZPO with the flexibility of PC, so that the phase interface fusion of the composite material ZPO / PC is significantly improved, and the cycle stability and service life of the battery are improved.

[0006] To achieve the above purpose, the present invention adopts the following technical solutions:

[0007] In the first aspect of the present invention, a zinc-iodine battery stabilized by inorganic / organic hybrid materials is provided. The zinc-iodine battery includes a positive electrode sheet, a negative electrode sheet, and an electrolyte; the positive electrode sheet contains an inorganic / organic hybrid material composed of a layered inorganic material and a cyclic two-dimensional organic material.

[0008] Preferably, the positive electrode sheet is prepared by the following method:

[0009] (1) Fully mix the layered inorganic material and the cyclic two-dimensional organic material to obtain an inorganic / organic hybrid material;

[0010] (2) Grind and mix the inorganic / organic hybrid material, conductive carbon, and binder, coat it on a current collector, and then drop I- An active material solution is obtained to get a positive electrode sheet.

[0011] Preferably, in step (1), the layered inorganic material is zirconium hydrogen phosphate; the cyclic two-dimensional organic material is phthalocyanine. The chemical formula of phthalocyanine is C 32 H 18 N 8 .

[0012] Preferably, in step (1), the mass ratio of the layered inorganic material to the cyclic two-dimensional organic material is 1:1.

[0013] Preferably, in step (1), the sufficient mixing is ball milling or dissolution and precipitation; the dissolution and precipitation specifically is: adding the cyclic two-dimensional organic material into an organic solvent to dissolve, then adding the layered inorganic material, and after dissolution, evaporating the organic solvent to obtain an inorganic / organic hybrid material.

[0014] The organic solvent is absolute ethanol.

[0015] Preferably, in step (2), the mass ratio of the inorganic / organic hybrid material, conductive carbon, and binder is 8:1:1.

[0016] The conductive carbon is acetylene black, and the binder is PVDF.

[0017] Preferably, the I - active substance contained in the active material solution - The active substance is selected from lithium iodide, sodium iodide, potassium iodide, ammonium iodide, or copper iodide.

[0018] Preferably, the I - active substance contained in the active material solution - The concentration of the active substance is 0.1 - 4.0 M.

[0019] Preferably, the negative electrode sheet is a zinc foil; the electrolyte is a zinc trifluoromethanesulfonate solution.

[0020] In the second aspect of the present invention, there is provided the application of the above zinc-iodine battery in improving the cycle stability and service life of the battery.

[0021] Advantages of the present invention:

[0022] (1) In the present invention, the inorganic layered material ZPO and the cyclic two-dimensional organic material PC are fully mixed to form an inorganic-organic hybrid interface layer. By combining the high strength and high modulus of the ZPO material with the flexibility of the PC material, the phase interface fusion of the composite material ZPO / PC is significantly improved. It not only solves the problem of I during the charging process +The problem of intermediate instability is solved, improving the Coulombic efficiency of the battery. Meanwhile, the cyclic conjugated system of PC can effectively capture and stabilize the intermediates (I - 、I 3 - 、I 5 - ) during these discharge processes, thus avoiding the shuttle effect of the intermediates in the electrolyte and enhancing the cycling performance of the battery. This unique innovative idea provides a simple and reliable method for improving the comprehensive performance of zinc-iodine batteries, brings new opportunities for the development of the energy storage field, and promotes the development of energy storage devices towards high efficiency, environmental friendliness, and safety.

[0023] (2) ZPO in the positive electrode sheet of the present invention belongs to a layered material and has a large specific surface area and surface charge, which can bind well with the intermediate I + ions, stabilize the I + ions, reduce its side reactions, and improve the Coulombic efficiency of the battery. The present invention utilizes the fact that the PC material has a cyclic 18-electron large conjugated system, which can effectively capture and stabilize the intermediates (I - 、I 3 - 、I 5 - ) during these discharge processes, achieving the effect of synergistically stabilizing the intermediates of the zinc-iodine battery. With the help of this inorganic / organic hybrid material, the present invention can directly use I⁻ as the electrode material, which is more conducive to the application of large-scale energy storage of zinc-iodine batteries. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 are the charge-discharge curves of the ordinary zinc-iodine battery prepared in Comparative Example 1 in the first 5 cycles at a current density of 0.5 A g -1 ;

[0025] Figure 2 is the X-ray diffraction pattern of ZPO in Comparative Example 2;

[0026] Figure 3 are the scanning electron microscope images and mapping images of ZPO in Comparative Example 2; among them, (a)-(c) are the scanning electron microscope images of ZPO at different magnifications; (d) is the mapping image of Zr element; (e) is the mapping image of P element; (f) is the mapping image of O element;

[0027] Figure 4 are the charge-discharge curves of the inorganic material zinc-iodine battery prepared in Comparative Example 2 in the first 5 cycles at a current density of 0.5 A g -1 ;

[0028] Figure 5 are the charge-discharge curves of the inorganic material zinc-iodine battery prepared in Comparative Example 2 at 2 A g-1 Battery performance graph for 1 - 100 cycles at a current density;

[0029] Figure 6 Stabilization mechanism diagram of ZPO in the inorganic material zinc - iodine battery prepared in Comparative Example 2;

[0030] Figure 7 X - ray diffraction spectrum of PC in Comparative Example 3;

[0031] Figure 8 Scanning electron microscope image and mapping images of PC in Comparative Example 3; where (a) - (c) are scanning electron microscope images of PC at different magnifications; (d) is the mapping image of C element; (e) is the mapping image of N element; (f) is the mapping image of O element;

[0032] Figure 9 Charge - discharge curves of the organic material zinc - iodine battery prepared in Comparative Example 3 in the first 5 cycles at 0.5 A g -1 ;

[0033] Figure 10 Battery performance graph for 1 - 100 cycles of the organic material zinc - iodine battery prepared in Comparative Example 3 at 2 A g -1 current density;

[0034] Figure 11 Stabilization mechanism diagram of PC in the organic material zinc - iodine battery prepared in Comparative Example 3;

[0035] Figure 12 X - ray diffraction spectrum of the ZPO / PC hybrid material prepared in the Example;

[0036] Figure 13 Scanning electron microscope image and mapping images of the ZPO / PC hybrid material prepared in the Example; where (a) - (c) are scanning electron microscope images of the ZPO / PC hybrid material at different magnifications; (d) is the mapping image of C element; (e) is the mapping image of N element; (f) is the mapping image of O element; (g) is the mapping image of Zr element; (h) is the mapping image of P element;

[0037] Figure 14 Charge - discharge curves of the zinc - iodine battery with synergistic stabilization of inorganic / organic hybrid material prepared in the Example in the first 5 cycles at 0.5 A g -1 current density;

[0038] Figure 15 Battery performance graph for 1 - 100 cycles of the zinc - iodine battery with synergistic stabilization of inorganic / organic hybrid material prepared in the Example at 2 A g -1 current density. DETAILED DESCRIPTION

[0039] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0040] As introduced in the background technology section, under normal conditions, zinc-iodine batteries use iodine as the active substance. However, the use of iodine requires solvent thermal or sublimation methods to prepare it into electrode sheets, that is, "iodine filling" is required to make electrode sheets, and the reaction must be carried out at high temperature.

[0041] Based on this, the purpose of the present invention is to provide a zinc-iodine battery with coordinated stability of inorganic / organic hybrid materials and its application. The present invention fully mixes the inorganic layered material zirconium hydrogen phosphate (ZPO) and the cyclic two-dimensional organic material phthalocyanine (PC) to form an inorganic-organic hybrid interface layer. Zirconium hydrogen phosphate (ZPO) is a new multifunctional mesoporous material and one of the layered solid acid materials. It has a large specific surface area and surface charge, good ion exchange properties, high thermal stability and acid and alkali resistance. Therefore, ZPO can be well combined with I + Ionic bonding, solidification + ions, reducing their side reactions and improving the coulombic efficiency of the battery. At the same time, phthalocyanine (PC) has a unique cyclic 18-electron conjugated system, and it is easy to form a two-dimensional layered structure between molecules. The cyclic conjugated system can effectively capture and stabilize the intermediates (I - ,I 3 - ,I 5 - ), thereby avoiding the shuttle effect of intermediates in the electrolyte. When ZPO is used alone to prepare the positive electrode sheet, it cannot inhibit the shuttle of water-soluble intermediates. When PC is used alone to prepare the positive electrode sheet, the strength is not enough and it is not compatible with I +The ion-binding ability is insufficient, so the performance of the positive electrode sheets prepared from these two materials alone is difficult to meet the requirements. By combining the high strength and high modulus of the ZPO material with the flexibility of the PC material to prepare the positive electrode sheet, the layered ZPO and layered PC materials can be fully mixed intermolecularly, making the mixing more uniform, achieving a large number of uniform inorganic-organic phase interfaces, and improving the phase interface fusion of the composite material ZPO / PC. During the charge and discharge process, the layered structure can better maintain its integrity, without significant volume changes or structural collapse, and can provide more active sites for adsorption, making the prepared zinc-iodine battery have better cycle stability and longer service life. In addition, when preparing the positive electrode sheet, the inorganic-organic hybrid interface layer formed by the inorganic layered material zirconium hydrogen phosphate (ZPO) and the cyclic two-dimensional organic material phthalocyanine (PC) does not require high-temperature "iodine filling", and only need to drop lithium iodide, sodium iodide, potassium iodide, ammonium iodide or copper iodide containing I - active substance solution, that is, greatly reducing the preparation difficulty and preparation safety, and simplifying the preparation process.

[0042] In order to enable those skilled in the art to more clearly understand the technical solution of the present application, the technical solution of the present application will be described in detail below in conjunction with specific embodiments.

[0043] The test materials used in the embodiments of the present invention are all conventional test materials in the art and can be obtained through commercial channels.

[0044] Example: Preparation of a zinc-iodine battery stabilized by an inorganic / organic hybrid material

[0045] S1. Preparation of the inorganic / organic hybrid material: Add 200 mg of PC powder to 100 mL of absolute ethanol and dissolve it after ultrasonic treatment for 20 min. Then add 200 mg of ZPO powder to it and ultrasonicate for 20 min to fully disperse ZPO into the ethanol solution, so that it can fully contact with the dissolved PC. Evaporate the solution on a heating table at 50 °C to obtain the inorganic / organic hybrid material denoted as ZPO / PC hybrid material.

[0046] S2. Preparation of the positive electrode sheet: Put the ZPO / PC hybrid material (80 mg) prepared in S1, conductive carbon acetylene black (10 mg) and binder PVDF (10 mg) into a mortar, add 200 μL of N-methylpyrrolidone (NMP), grind and mix thoroughly, and coat it on a circular titanium foil metal (diameter: 10 mm, thickness: 100 μm) current collector, and dry it in vacuum at 70 °C for 8 h. Subsequently, drop 80 μL of a potassium iodide solution with a concentration of 0.2 M on its surface and let it stand and dry at room temperature to make the active substance I - fully contact and enter the internal electrode material to obtain the positive electrode sheet.

[0047] S3. Assembly of zinc-iodine battery: Using a zinc foil (diameter: 10 mm; thickness: 100 μm) as the negative electrode, zinc trifluoromethanesulfonate (concentration: 3M, 150 μL) as the electrolyte, and a glass fiber (diameter: 16 mm; thickness: 100 μm) as the separator, assemble with the positive electrode sheet prepared in S2 to obtain a 2032 battery, which is a zinc-iodine battery stabilized by inorganic / organic hybrid materials, and test its electrochemical performance.

[0048] Figure 12 XRD pattern of the ZPO / PC hybrid material prepared in S1 of the example. Its characteristic peaks show obvious characteristic peaks of ZPO, and at the same time, a PC peak appears near 5°, proving the successful compounding of the hybrid material.

[0049] Figure 13 SEM image of the ZPO / PC hybrid material prepared in S1 of the example. The lamellae of ZPO are still maintained, and its surface becomes rough due to the compounding of PC material. Zr element, P element, C element, N element, and O element are evenly distributed in the sample.

[0050] Figure 14 Charge-discharge curves of the zinc-iodine battery stabilized by inorganic / organic hybrid materials prepared in the example at 0.5 A g -1 for the first 5 cycles. The initial discharge capacity is 235 mAh g -1 , and after 5 cycles, its capacity becomes 227 mAh g -1 , and the Coulombic efficiency can still be maintained at 99%. Both the capacity and the Coulombic efficiency are higher than those of Comparative Example 1, and the Coulombic efficiency and cycling performance have been improved.

[0051] Figure 15 Long-term cycling curves of the zinc-iodine battery stabilized by inorganic / organic hybrid materials prepared in the example at a current density of 2 A g -1 . The specific discharge capacity of the battery decreases from 138 mAh g -1 to 130 mAh g -1 after 100 cycles, and the Coulombic efficiency remains at 99%, indicating that the ZPO / PC hybrid material can synergistically stabilize the intermediates (I + , I - , I 3 - , I 5 - ) of the zinc-iodine battery and improve the electrochemical performance of the battery.

[0052] The schematic diagram of the stabilization mechanism is as shown in Figure 6 and Figure 11 . Due to the easy exchange between the hydrogen ions in the ZPO structure and I + , ZPO can effectively stabilize I+ suppresses its hydrolysis reaction. On the other hand, the conjugated system in the PC ring structure can adsorb the intermediate (I - 、I 3 - 、I 5 - ), inhibiting its dissolution in water, thereby improving the stability of the battery.

[0053] Comparative Example 1: Preparation of a conventional zinc-iodine battery

[0054] S1. Preparation of the positive electrode sheet: Put conductive carbon acetylene black (90 mg) and binder PVDF (10 mg) into a mortar, add 200 μL of NMP solvent and grind them thoroughly, then coat it on a circular titanium foil metal (diameter: 10 mm; thickness: 100 μm) current collector, and dry it in vacuum at 70 °C for 8 h. Subsequently, 80 μL of potassium iodide solution (0.2 M) was dropped on its surface and left to dry at room temperature, so that the active substance I - fully contacted and entered the interior of the electrode material.

[0055] S2. Assembly of the zinc-iodine battery: Using the positive electrode sheet prepared in S1, zinc foil (diameter: 10 mm; thickness: 100 μm) as the negative electrode, zinc trifluoromethanesulfonate (3 M, 150 μL) as the electrolyte, and glass fiber (diameter: 16 mm; thickness: 100 μm) as the separator to assemble a 2032 battery, which is a conventional zinc-iodine battery, and its electrochemical performance was tested.

[0056] Figure 1 Figure shows the charge-discharge curves of the zinc-iodine battery prepared in Comparative Example 1 in the first 5 cycles at 0.5 A g -1 , its Coulomb efficiency is about 93%, and the discharge capacity is 23 mAh g -1 . After only 5 cycles, its capacity decreased to 16.5 mAh g -1 , indicating that without the synergistic stabilization of inorganic / organic hybrid materials, when the zinc-iodine battery uses potassium iodide as the active substance, the side reactions are serious and the shuttle effect is serious, resulting in poor battery performance.

[0057] Comparative Example 2: Preparation of an inorganic material zinc-iodine battery

[0058] S1. Preparation of the positive electrode sheet: Put ZPO (80 mg), conductive carbon acetylene black (10 mg) and binder PVDF (10 mg) into a mortar, add 200 μL of NMP and grind them thoroughly, then coat it on a circular titanium foil metal (diameter: 10 mm; thickness: 100 μm) current collector, and dry it in vacuum at 70 °C for 8 h. Subsequently, 80 μL of potassium iodide solution (0.2 M) was dropped on its surface and left to dry at room temperature, so that the active substance I -Fully contact and enter into the interior of the electrode material.

[0059] S2. Assembly of the zinc-iodine battery: The prepared positive electrode sheet, zinc foil (diameter: 10 mm; thickness: 100 μm) as the negative electrode, zinc trifluoromethanesulfonate (3M, 150 μL) as the electrolyte, and glass fiber (diameter: 16 mm; thickness: 100 μm) as the separator were used to assemble a 2032 battery, which is an inorganic material zinc-iodine battery, and its electrochemical performance was tested.

[0060] Figure 2 It is the XRD pattern of ZPO in Comparative Example 2. Its characteristic peaks are consistent with the standard card and there are no additional characteristic peaks, proving that ZPO is a pure phase.

[0061] Figure 3 It is the SEM image of ZPO in Comparative Example 2. ZPO shows a lamellar structure with a size of approximately 0.5 - 1.5 μm. The Zr element, P element, and O element are evenly distributed in the sample, proving that ZPO is a uniform layered material.

[0062] Figure 4 It is the charge-discharge curves of the inorganic material zinc-iodine battery prepared in Comparative Example 2 at 0.5 A g -1 for the first 5 cycles. Its Coulomb efficiency reaches 99%. Compared with Comparative Example 1, the introduction of ZPO is beneficial to stabilizing I + ions, reducing its side reactions, and improving the Coulomb efficiency of the battery.

[0063] Figure 5 It is the 100-cycle long-term cycling curve of the inorganic material zinc-iodine battery prepared in Comparative Example 2 at a current density of 2 A g -1 The discharge specific capacity of the battery decreased from 78 mAh g -1 to 66 mAh g -1 after 100 cycles, and the Coulomb efficiency was 98%, indicating that ZPO is beneficial to stabilizing I + intermediates and improving the Coulomb efficiency.

[0064] The schematic diagram of the mechanism of its stabilization mechanism is as shown in Figure 6 Since the hydrogen ions in the ZPO structure are prone to exchange with I + , ZPO can effectively stabilize I + , inhibit its hydrolysis reaction, and thus improve the Coulomb efficiency.

[0065] There are two obvious plateaus in the charge-discharge curve of Comparative Example 2, indicating that ZPO can effectively stabilize I + , and can realize the two-step reaction of I - —I + . The capacity and Coulomb efficiency are also improved. However, the intermediate (I -, I 3 - , I 5 - Due to the existence of the shuttle effect, its cycling performance is poor and there is still attenuation. While in the examples, the use of inorganic-organic hybrid materials can improve the capacity and Coulomb efficiency, and at the same time, the cycling performance has also been greatly improved.

[0066] Comparative Example 3: Preparation of an organic material zinc-iodine battery

[0067] S1. Preparation of the positive electrode sheet: Put PC (80 mg), conductive carbon acetylene black (10 mg), and binder PVDF (10 mg) into a mortar, add 200 μL of NMP and grind and mix thoroughly, then coat it on a circular titanium foil metal (diameter: 10 mm; thickness: 100 μm) current collector, and dry it in vacuum at 70 °C for 8 h. Subsequently, drop 80 μL of potassium iodide solution (0.2 M) on its surface and let it stand and dry at room temperature to allow the active substance I - to come into full contact and enter the interior of the electrode material.

[0068] S2. Assembly of the zinc-iodine battery: Use the prepared positive electrode sheet, zinc foil (diameter: 10 mm; thickness: 100 μm) as the negative electrode, zinc trifluoromethanesulfonate (3 M, 150 μL) as the electrolyte, and glass fiber (diameter: 16 mm; thickness: 100 μm) as the separator to assemble a 2032 battery, which is the organic material zinc-iodine battery, and test its electrochemical performance.

[0069] Figure 7 Figure 21 shows the XRD spectrum of PC in Comparative Example 3. The presence of characteristic peaks indicates the π-π conjugate structure in the organic material PC molecules.

[0070] Figure 8 Figure 25 shows the SEM image of PC in Comparative Example 3. PC presents particles, and C, N, and O elements are evenly distributed in the sample.

[0071] Figure 9 Figure 29 shows the charge-discharge curves of the organic material zinc-iodine battery prepared in Comparative Example 3 in the first 5 cycles at 0.5 A g -1 . The initial discharge capacity is 138 mAh g -1 . After 5 cycles, its capacity becomes 101 mAh g -1 . The capacity is higher than that of Comparative Example 1, and the cycling has been improved.

[0072] Figure 10 Figure 39 shows the 100-cycle long cycling curve of the organic material zinc-iodine battery prepared in Comparative Example 3 at a current density of 2 A g -1 . The discharge specific capacity of the battery decreases from 97 mAh g after 100 cycles -1Drop to 85 mAh g -1 , indicating that PC can effectively capture and stabilize the intermediates (I - , I 3 - , I 5 - ) during these discharge processes, improving the cycling performance of the battery.

[0073] The schematic diagram of the stabilization mechanism is as shown in Figure 11 . Due to the conjugated system in the cyclic structure of PC, it can adsorb the intermediates (I - , I 3 - , I 5 - ), inhibiting their dissolution in water, thereby improving the stability of the battery.

[0074] In the cycling performance graph of Comparative Example 3, it can be seen that since PC can adsorb the intermediates (I - , I 3 - , I 5 - ) during the reaction process, the shuttle effect is inhibited, thus improving the cycling performance of the battery. However, only one obvious plateau appears in the charge-discharge curve, and the plateau at high potential is not obvious. This is because the PC material cannot stabilize the I + ions, resulting in a relatively lower capacity in Comparative Example 3 compared to the Examples. In the Examples, the use of inorganic-organic hybrid materials can improve the cycling performance while also significantly improving the capacity and Coulomb efficiency.

[0075] The above are only the preferred embodiments of the present application and are not used to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application.

Claims

1. A zinc-iodine battery with coordinated stabilization of inorganic / organic hybrid materials, characterized in that: The zinc-iodine battery comprises a positive electrode sheet, a negative electrode sheet and an electrolyte; the positive electrode sheet contains an inorganic / organic hybrid material composed of a layered inorganic material and a ring-shaped two-dimensional organic material; The positive electrode sheet is prepared by the following method: (1) Fully mixing a layered inorganic material and a cyclic two-dimensional organic material to obtain an inorganic / organic hybrid material; the layered inorganic material is zirconium hydrogen phosphate; the cyclic two-dimensional organic material is phthalocyanine; the mass ratio of the layered inorganic material to the cyclic two-dimensional organic material is 1:1; the full mixing is ball milling or dissolution separation; The dissolution separation is specifically as follows: adding the cyclic two-dimensional organic material to an organic solvent to dissolve it, then adding the layered inorganic material, and after the material is dissolved, evaporating and removing the organic solvent to obtain an inorganic / organic hybrid material; (2) The inorganic / organic hybrid material, conductive carbon and binder are ground and mixed, coated on the current collector and then dripped with I - Active material solution, to obtain a positive electrode sheet; said I - Active substance solution contains I - The active substance is selected from lithium iodide, sodium iodide, potassium iodide, ammonium iodide or copper iodide; - Active substance solution contains I - The concentration of active substances is 0.1~4.0M; The electrolyte is a zinc trifluoromethanesulfonate solution.

2. The zinc-iodine battery according to claim 1, characterized in that: In step (2), the mass ratio of the inorganic / organic hybrid material, the conductive carbon and the binder is 8:1:

1.

3. The zinc-iodine battery according to claim 1, characterized in that: The negative electrode sheet is zinc foil.

4. Application of the zinc-iodine battery according to any one of claims 1 to 3 in improving the cycle stability and service life of the battery.

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