Regulated Ion‐Conductive Electrode–Electrolyte Interface by In Situ Gelation for Stable Zinc Metal Anode

Abstract Dendritic growth and severe side reactions remain challenging problems for advancing aqueous zinc‐ion batteries. Those critical issues are closely related to the interfacial chemistry, solvation structure, and transportation kinetics of zinc ions. Herein, a regulated ion‐conductive electrode–electrolyte interface (PVA‐Zn(CF3SO3)2‐Si3N4, denoted as PZS) on Zn metal has been in situ constructed, which simultaneously solves the above‐mentioned issues. PZS can effectively accelerate ion transportation and extrude interfacial water, thus endowing dendrite‐free Zn deposition and eliminating side reactions. Benefiting from these features, the PZS‐Zn exhibits stable and reversible Zn stripping/plating with an ultralong cycling life of 3800 h, and an ultrahigh Coulombi efficiency of 99.8%. The full cell paired with the NH4V4O10 cathode runs stably over 1000 cycles at 5 A g−1 with near 100% capacity retention and is demonstrated to cycle up to 200 times along with 71.94% capacity retention in a practical cathode‐anode coupling configuration pouch cell. With this interfacial design, the assembled zinc batteries display excellent cycling stability, paving a practical way for aqueous Zn‐storage systems.