Mapping the Design of Electrolyte Materials for Electrically Rechargeable Zinc–Air Batteries

Electrically rechargeable zinc-air batteries (ERZABs) have attracted substantial research interest as one of the best candidate power sources for electric vehicles, grid-scale energy storage, and portable electronics owing to their high theoretical capacity, low cost, and environmental benignity. However, the realization of ERZABs with long cycle life and high energy and power densities is still a considerable challenge. The electrolyte, which serves as the ionic conductor, is one of the core components of ERZABs, as it plays a significant role during the discharge-charge process and greatly influences the rechargeability, operating voltage, lifespan, power density, and safety of ERZABs. Herein, the fundamental electrochemistry of electrolyte materials for ERZABs and the associated challenges are presented. Furthermore, recent advances in electrolyte materials for ERZABs, including alkaline aqueous electrolytes, nonalkaline electrolytes, ionic liquids, and semisolid-state electrolytes are discussed. This work aims to provide insights into the future exploration of high-performance electrolytes and thus promote the development of ERZABs.