Issues and rational design of aqueous electrolyte for Zn‐ion batteries

Abstract Aqueous Zn‐ion batteries (AZIBs) are regarded as a promising alternative to the widely used lithium‐ion batteries in large‐scale energy storage systems. The researches on the development of novel aqueous electrolyte to improve battery performance have also attracted great interest since the electrolyte is a key component for Zn 2+ migration between cathode and anode. Herein, we briefly summarized and illuminated the recent development tendency of aqueous electrolyte for AZIBs, then deeply analyzed its existing issues (water decomposition, cathode dissolution, corrosion and passivation, and dendrite growth) and discussed the corresponding optimization strategies (pH regulation, concentrated salt solution, electrolyte composition design, and functional additives). The internal mechanisms of these strategies were further revealed and the relationships between issues and solutions were clarified, which could guide the future development of aqueous electrolytes for AZIBs.