Advancing aqueous zinc-Ion batteries through polymer interface engineering: from mechanisms to applications

Abstract

Aqueous zinc-ion batteries (AZIBs) have attracted considerable attention as energy storage system with the advantages of high safety and low cost. However, dendrite growth and side reactions of zinc anodes severely limit their cycle life. Polymer materials have become a crucial tactic to improve the stability of zinc anodes because of their unique interface management capabilities and designable functional groups. This review systematically summarizes the research progress of polymer protective layers in AZIBs. Starting from the challenges faced by the zinc anodes, the advantages and main action mechanisms of polymers as protective layers are discussed in depth. Studies have shown that polymer protective layers can significantly improve the cycle stability of zinc anodes. Nevertheless, low ionic conductivity, high cost, and difficulties in large-scale fabrication remain bottlenecks. In the future, it is necessary to develop multifunctional polymer systems, clarify interfacial dynamics through in-situ characterization techniques, and promote the application of biodegradable materials in flexible devices. Through mechanism innovation and engineering optimization, polymer protective layers will provide key solutions for the practical application of high-stability AZIBs.