CN-122025854-A - Aqueous zinc ion battery electrolyte and preparation method and application thereof

Abstract

The invention discloses a water-based zinc ion battery electrolyte, a preparation method and application thereof, wherein the electrolyte comprises zinc salt, an additive and deionized water, the additive is benzyl trimethyl ammonium bromide, and the concentration of the additive is 0.1-0.2 mol/L compared with the electrolyte. The invention successfully realizes the construction of the dynamic hydrophobic layer and inhibits side reactions such as hydrogen evolution corrosion and the like. Meanwhile, hydrophilic groups at the outermost side of the hydrophobic layer can also reduce a desolvation energy barrier of Zn 2+ , improve deposition/dissolution kinetics of Zn 2+ and further prolong the cycle life of the water-based zinc ion battery. In addition, the introduction of the anions Br − not only can destroy the original hydrogen bond network, inhibit the activity of water and reduce side reactions, but also can activate I + ions, excite a high-voltage discharge platform and improve the capacity of the zinc-iodine battery. Therefore, the electrolyte can improve the cycle stability of the zinc-iodine battery, and the preparation method is simple and efficient, has low cost and important practical value.

Inventors

• ZHANG XINBO
• CHEN CHUNLING
• LIU JIANWEI
• HUANG GANG
• LIU TONG
• ZHUANG ZHENBANG

Assignees

• 中国科学院长春应用化学研究所

Dates

Publication Date

20260512

Application Date

20260116

Claims (10)

1. 1. The aqueous zinc ion battery electrolyte is characterized by comprising zinc salt, an additive and deionized water; Wherein the additive is benzyl trimethyl ammonium bromide, and the concentration of the additive in the electrolyte is 0.1-0.2 mol/L.
2. 2. The aqueous zinc-ion battery electrolyte of claim 1 wherein the zinc salt comprises one or more of ZnSO 4 、Zn(OTf) 2 、ZnCl 2 、Zn(ClO 4 ) 2 、Zn(BF 4 ) 2 、Zn(TFSI) 2 、Zn(Ac) 2 .
3. 3. The aqueous zinc-ion battery electrolyte according to claim 2, wherein the concentration of zinc salt in the electrolyte is 1-3 mol/L.
4. 4. The method for preparing an aqueous zinc-ion battery electrolyte according to any one of claim 1 to 3, comprising, And uniformly mixing zinc salt, an additive and deionized water to obtain the aqueous zinc ion battery electrolyte.
5. 5. The use of the aqueous zinc-ion battery electrolyte according to any one of claims 1 to 3 for the preparation of aqueous zinc-ion batteries.
6. 6. A preparation method of a water-based zinc ion battery is characterized by comprising the following steps of, Injecting the electrolyte according to any one of claims 1-3 into a glass fiber diaphragm, and assembling the electrolyte with a zinc foil negative electrode and a positive electrode together to obtain a battery; Wherein the material of the positive electrode comprises one of copper foil, zinc foil, titanium foil and iodine pole piece.
7. 7. The method for preparing the aqueous zinc-ion battery according to claim 6, wherein the method for preparing the iodine electrode sheet comprises the steps of, Mixing the iodine-loaded activated carbon powder, the conductive carbon black and the binder according to the mass ratio of 6-7:3-2:1, adding deionized water, and uniformly stirring to form slurry; Uniformly coating the slurry on a substrate, and controlling the iodine loading to be 0.75-1.25 mg/cm 2 ; and (3) drying the coated slurry, peeling, pressing and attaching the slurry to a titanium mesh, and cutting into iodine pole pieces with the diameter of 10-12 mm.
8. 8. The method for producing an aqueous zinc-ion battery according to claim 7, wherein the method for producing the iodine-supported activated carbon powder comprises, And placing the activated carbon and iodine into a sealed container, and performing heat treatment for 10-12 hours at 60-75 ℃ by adopting a vapor deposition method, wherein the mass fraction of the iodine in the product is controlled to be 30-35 wt%, so as to obtain the activated carbon powder loaded with the iodine.
9. 9. The method for preparing a water-based zinc ion battery according to claim 7, wherein the conductive carbon black comprises one or more of Super P, acetylene black, carbon nanotubes, graphene and Ketjen black, and the binder comprises one or more of polytetrafluoroethylene and polyvinylidene fluoride.
10. 10. The method according to any one of claims 6 to 9, wherein the aqueous zinc ion battery is produced.

Description

Aqueous zinc ion battery electrolyte and preparation method and application thereof Technical Field The invention belongs to the technical field of water-based zinc ion batteries, and particularly relates to a water-based zinc ion battery electrolyte, a preparation method and application thereof. Background With the global growing demand for renewable energy storage and electric vehicles, it is important to develop safe, efficient, low cost electrochemical energy storage systems. Although lithium ion batteries predominate in the marketplace, their inherent safety risks (such as flammability and explosiveness of organic electrolytes), high cost, and limited lithium resources limit their further use in the field of large-scale energy storage. The water-based zinc ion battery is used as an emerging energy storage system, has multiple advantages of high theoretical capacity (820 mAh/g or 5855 mAh/cm < 3 >) of a zinc cathode, low oxidation-reduction potential (-0.76V vs. SHE), abundant storage capacity of zinc resource crust and low price, and simultaneously, adopts an aqueous solution as electrolyte, thereby thoroughly eliminating the risk of easy combustion and easy explosion of the electrolyte. Therefore, the aqueous zinc ion battery is widely focused on the advantages of high safety, low cost and environmental friendliness, and is considered as one of the candidates with great potential in the future large-scale energy storage field. However, the practical application of the current water-based zinc ion battery is still limited by the problems of short cycle life, low coulombic efficiency and the like, and the main reason is that the compatibility of the zinc cathode and the water-based electrolyte is poor, and a series of side reactions such as hydrogen evolution reaction, corrosion, surface passivation and the like are easy to initiate, so that zinc dendrite growth is further increased, and the performance and the service life of the battery are influenced. In order to solve the above problems, researchers have proposed various strategies, but all have certain limitations. For example, the cathode is modified by constructing a three-dimensional metallic zinc cathode or surface coating to enhance interface stability and improve battery cycle performance, but the method has complex process and high cost and is difficult to popularize on a large scale, and the high-concentration electrolyte reduces free water molecules by utilizing a salt water-in-package strategy and inhibits hydrogen evolution side reaction, but the method can lead to the increase of the viscosity of the electrolyte, reduce the ionic conductivity and influence the battery performance. Therefore, there is a need to develop a new electrolyte system that is efficient, stable and economical to further improve the cycle performance of the aqueous zinc ion battery. Disclosure of Invention This section is intended to outline some aspects of embodiments of the application and to briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section as well as in the description of the application and in the title of the application, which may not be used to limit the scope of the application. The present invention has been made in view of the above and/or problems occurring in the prior art. Therefore, the invention aims to overcome the defects in the prior art and provide the aqueous zinc ion battery electrolyte. In order to solve the technical problems, the invention provides the following technical proposal that the electrolyte comprises zinc salt, additive and deionized water; Wherein the additive is benzyl trimethyl ammonium bromide, and the concentration of the additive in the electrolyte is 0.1-0.2 mol/L. As a preferable scheme of the water-based zinc ion battery electrolyte, the zinc salt comprises one or more of ZnSO4、Zn(OTf)2、ZnCl2、Zn(ClO4)2、Zn(BF4)2、Zn(TFSI)2、Zn(Ac)2. As a preferable scheme of the water-based zinc ion battery electrolyte, the concentration of zinc salt in the electrolyte is 1-3 mol/L. The invention further aims to overcome the defects of the prior art and provide a preparation method of the water-based zinc ion battery electrolyte. In order to solve the technical problems, the invention provides the following technical proposal that comprises, And uniformly mixing zinc salt, an additive and deionized water to obtain the aqueous zinc ion battery electrolyte. It is still another object of the present invention to overcome the deficiencies of the prior art and to provide an application of an aqueous zinc ion battery electrolyte in the preparation of an aqueous zinc ion battery. It is still another object of the present invention to provide a method for preparing an aqueous zinc ion battery that overcomes the deficiencies of the prior art. In order to solve the technical problems, the invention provides the following technical proposal that comprises, Injecting the electrolyte according t