Recent progress in biomass-derived and functional polymer binders for aqueous zinc metal batteries

Aqueous zinc-metal batteries (AZBs) have become a key research focus for large-scale energy storage, owing to their intrinsic safety, low cost, and environmental friendliness. Although extensive work has addressed anodes, cathodes, separators, and electrolytes, the binder also plays a critical role in electrode fabrication and significantly affects the redox kinetics of AZB electrodes. However, binders have received limited attention in this field, and no systematic review has yet summarized binder design specifically for aqueous batteries. This review comprehensively covers recent advances in AZB binders, categorizes their functional mechanisms and optimization strategies, and offers perspectives on remaining challenges to guide the rational design of high-performance binders.