Electrolytes for Aqueous Zinc‐Ion Batteries

The electrolyte is the key to connecting the anode and cathode, and its design and optimization strategy are related to battery performance. In addition to the alkaline electrolyte, aqueous zinc-ion batteries (AZIBs) have been developed in neutral or mildly acidic electrolytes in recent years. In an aqueous medium, composition and salt concentration have an important influence on the intrinsic properties and electrochemical performance of electrolytes. To optimize the design of the electrolyte by adjusting pH, selecting zinc salt, introducing additives, changing concentration, and changing solvent, in the final analysis, the interface of the electrode will be affected when the electrolyte contacts the electrode directly. Cathode-electrolyte interphase plays an important role in preventing cathode dissolution and improving the electrochemical performance of aqueous ZIB. A wide voltage window to maintain the inherent stability of aqueous solvents during the electrochemical process is a prerequisite for high-performance AZIBs.