Molecular‐Level Design of Multifunctional Membranes: A Holistic Approach for High‐Performance Aqueous Zinc Metal Batteries

Abstract In the pursuit of the development of safe energy storage devices, aqueous zinc metal batteries have garnered incredible attention due to their non‐flammable nature and high energy densities. However, they suffer from severe complicated degradations induced by dendrite formation, hydrogen evolution reaction, transition metal dissolution, and their crosstalk effect. Herein, membranes are designed and engineered for high mechanical strength, Zn ²⁺ selectivity, and hydrophobicity to simultaneously address the complex degradations. The prevention of dendrite formation and crosstalk‐induced side reactions results in high reversibility of Zn metal anodes with a high average CE of 99.73% and an excellent cycle life in full cells with a capacity retention of 88.87% after 1000 cycles. This result highlights the importance of crosstalk prevention in the separator and offers the design principle of novel membranes for aqueous Zn metal batteries, advancing toward commercial level without requiring major modifications to the overall system.