Recent Progress in Aqueous Zinc-ion Batteries: a Deep Insight into Zinc Metal Anodes

Aqueous zinc ion batteries (AZIBs) have recently sparked an enormous surge of research attention, due to their environmental benignity, natural abundance, negligible safety issue, and exceptional electrochemical performance. Despite the rapid progress in designing a kind of exceptional cathode material with high compatibility to the aqueous electrolyte, the potential issues on the zinc anode side should not be underestimated, including dendrite growth, Zn corrosion, and hydrogen evolution. Herein, the origin of the above problems is outlined from the perspective of thermodynamics, and the optimization strategies of Zn are accordingly discussed and summarized in two aspects: the anode and the electrolyte. Finally, some general guidance and suggested future research directions for high-performance Zn anodes are proposed, aiming to further prolong cycling lifespan and promote commercialization of AZIBs.