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CN-121983682-A - Guanidine-containing hydrobromide electrolyte for high-energy-density zinc-bromine-iodine battery, and preparation method and application thereof

CN121983682ACN 121983682 ACN121983682 ACN 121983682ACN-121983682-A

Abstract

The application relates to guanidine-containing hydrobromide electrolyte for a high-energy-density zinc-bromine-iodine battery, and a preparation method and application thereof, and belongs to the technical field of water-based zinc-bromine-iodine batteries. The guanidine-containing hydrobromide electrolyte for the high-energy-density zinc-bromine-iodine battery comprises guanidine hydrobromide, zinc salt and deionized water. The guanidine-containing hydrobromide electrolyte for the high-energy-density zinc-bromine-iodine battery provided by the application can simultaneously realize iodine valence state I ‑ I 0 I + oxidation-reduction and bromine valence Br The oxidation reduction of Br 0 realizes the six-electron transfer of the halogen intermetallic compound in the zinc-bromine-iodine battery. On one hand, the application improves the energy density of the battery to 3-4 times of the initial value, and on the other hand, the zinc-bromine-iodine battery has the advantages of easy manufacture and easy industrialized popularization.

Inventors

  • SHI XIAODONG
  • WANG JIA
  • QIU CHAO
  • YANG MINGHAN
  • TIAN XINLONG
  • YANG YUTING

Assignees

  • 海南大学

Dates

Publication Date
20260505
Application Date
20260203

Claims (10)

  1. 1. A guanidine-containing hydrobromide electrolyte for a high energy density zinc-bromine-iodine battery, comprising guanidine hydrobromide, zinc salt and deionized water.
  2. 2. The guanidine hydrobromide-containing electrolyte for a high energy density zinc bromine iodine battery according to claim 1 wherein the molar concentration of guanidine hydrobromide is 0.1-10 mol kg -1 .
  3. 3. The guanidine hydrobromide-containing electrolyte for a high energy density zinc bromine iodine battery according to claim 1 wherein the purity of guanidine hydrobromide is 97-99.9%.
  4. 4. The guanidine-containing hydrobromide electrolyte for a high energy density zinc-bromine-iodine battery according to claim 1 wherein the zinc salt comprises zinc salt a and zinc salt B, the zinc salt a being at least one selected from the group consisting of zinc bis (trifluoromethylsulfonyl) imide, zinc triflate, zinc sulfate, zinc chloride, zinc fluoride, zinc perchlorate, and the zinc salt B being zinc bromide.
  5. 5. The guanidine-containing hydrobromide electrolyte for a high energy density zinc-bromine-iodine battery according to claim 4 wherein the molar concentration of zinc salt a is 1.0-10.0 mol kg -1 and the molar concentration of zinc salt B is 0.1-10.0 mol kg -1 .
  6. 6. The guanidine-containing hydrobromide electrolyte for a high energy density zinc-bromine-iodine battery according to claim 4 wherein the purity of the zinc salt a is 95-99.999% and the purity of the zinc salt B is 98-99.999%.
  7. 7. A method for preparing the guanidine-containing hydrobromide electrolyte for the high-energy-density zinc-bromine-iodine battery according to any one of claims 1to 6, comprising the following steps: And then adding guanidine hydrobromide, and fully stirring and mixing to obtain the guanidine hydrobromide-containing electrolyte for the high-energy-density zinc bromine-iodine battery.
  8. 8. A high energy density zinc bromine iodine battery comprising an iodine-containing positive electrode, a separator, a metallic zinc negative electrode and the guanidine-containing hydrobromide electrolyte for the high energy density zinc bromine iodine battery of any one of claims 1 to 6.
  9. 9. The high energy density zinc-bromine-iodine battery according to claim 8 wherein a ratio of a weight of guanidine-containing hydrobromide electrolyte to a capacity of the high energy density zinc-bromine-iodine battery is 5-50 g Ah -1 and a ratio of a capacity of the metallic zinc negative electrode to a capacity of the iodine-containing positive electrode is 1.5-20.
  10. 10. The high energy density zinc bromine iodine battery according to claim 8 wherein the separator material is fiberglass.

Description

Guanidine-containing hydrobromide electrolyte for high-energy-density zinc-bromine-iodine battery, and preparation method and application thereof Technical Field The application relates to the technical field of water-based zinc-bromine-iodine batteries, in particular to guanidine-containing hydrobromide electrolyte for a high-energy-density zinc-bromine-iodine battery, and a preparation method and application thereof. Background Energy storage devices are an important approach for energy conversion and multi-element technology development. For example, power supply is the most fundamental guarantee of explosive growth of the Al industry. Commercial energy storage products dominated by lithium ion batteries still have the risk of flammability, and aqueous batteries are expected to become an important device for the next generation energy storage market by virtue of incombustibility. The low energy density of aqueous batteries has hampered its own commercialization. Iodine positive electrode of traditional zinc-iodine battery is I -The redox between I 0 provides battery capacity, each elemental iodine can realize two electron transfer, and the theoretical gram capacity of the positive electrode is 211 mAh g -1. Although the gram capacity of the positive electrode is comparable to the gram capacity of the polycrystalline/single crystal ternary positive electrode material commercialized in excellent lithium ion batteries. The energy density of the battery is affected by gram capacity of the anode and the cathode, the consumption of electrolyte, working voltage and surface loading. The water-based zinc-iodine battery is limited by the inherent oxidation-reduction potential of the water solvent, and the working voltage (0.4-2V) of the water-based zinc-iodine battery is far lower than the working voltage (2-4V) of a commercial lithium ion battery. Increasing the surface loading or achieving more multivalent halogen ion electron transfer is critical to increasing the energy density of the cell. The low conductivity of the iodine simple substance leads to the polarization aggravation and the rapid capacity decay of the zinc-iodine battery under high load, and is not suitable for the development of the current large device. Currently, more electron transfer is achieved at limited operating voltages, and increasing the faraday current of the battery capacity is the most effective measure. If can realize I -And I +, wherein each iodine simple substance can realize four-electron transfer, and the theoretical gram capacity is 422 mAh g -1. In addition, br -The redox between Br 0 allows each elemental bromine to provide two electron transfer, with gram capacity up to 335 mAh g -1. At the same time realize iodine valence (I) -I0I +) and bromine valence (Br) -Br 0) in the form of a six electron transfer, then a multiple increase in cell energy density is achieved. Disclosure of Invention In view of the above, the application provides a guanidine hydrobromide electrolyte for a high energy density zinc bromine iodine battery, a preparation method and application thereof, and the electrolyte can excite I 0I + and Br -The redox of Br 0 can effectively overcome the defects existing in the prior art. In a first aspect, the application provides a guanidine-containing hydrobromide electrolyte for a high energy density zinc-bromine-iodine battery, comprising guanidine hydrobromide, zinc salt and deionized water. Preferably, the mass molar concentration of the guanidine hydrobromide is 0.1-10 mol kg -1. Specifically, the mass molar concentration of the guanidine hydrobromide is 0.4-2 mol L -1. Preferably, the purity of the guanidine hydrobromide is 97-99.9%. Specifically, the purity of the guanidine hydrobromide is 99-99.9%, which is a commercially available salt in the field. Preferably, the zinc salt comprises zinc salt A and zinc salt B, wherein the zinc salt A is at least one of zinc bis (trifluoromethylsulfonyl) imide, zinc trifluoromethane sulfonate, zinc sulfate, zinc chloride, zinc fluoride and zinc perchlorate, and the zinc salt B is zinc bromide. Specifically, both zinc salt a and zinc salt B are commercially available in the art. Preferably, the molar concentration of the zinc salt A is 1.0-10.0 mol kg -1, and the molar concentration of the zinc salt B is 0.1-10.0 mol kg -1. Specifically, the molar concentration of the zinc salt A is 4.0-6.0 mol kg -1, and the molar concentration of the zinc salt B is 0.5-1.0 mol kg -1. Preferably, the purity of the zinc salt A is 95-99.999%, and the purity of the zinc salt B is 98-99.999%. Specifically, the purity of the zinc salt A is 98-99.999%, and the purity of the zinc salt B is 99.9-99.999%. The second aspect of the application also provides a preparation method of the guanidine-containing hydrobromide electrolyte for the high-energy-density zinc-bromine-iodine battery, which comprises the following steps: And then adding guanidine hydrobromide, and fully stirring and mixing to obt