A Co‐Solvent Hydrogel Electrolyte for High‐Temperature and Anti‐Corrosion Zinc‐Ion Batteries

ABSTRACT Flexible aqueous zinc‐ion batteries (FAZIBs) hold significant potential as efficient energy storage devices for wearable electronics, owing to their cost‐effectiveness and enhanced safety. However, the poor corrosion resistance of Zn anodes remains a critical challenge hindering the development of high‐performance AZIBs. Leveraged the synergistic effect of tetramethylurea (TMU) and polyacrylamide (PAM), this work proposes a composite hydrogel electrolyte (PMT) based on the TMU‐H 2 O binary solvent. The zincophilic functional groups alter the solvation structure of Zn 2+ , reducing the activity of free water. Therefore, batteries assembled with this electrolyte exhibited exceptional corrosion resistance, effectively suppressing side reactions and dendrite growth. Zn||Zn cells demonstrate stable cycling for 2100 h at room temperature while maintaining a cycling lifespan exceeding 500 h at 50°C. This study provides fundamental insights into the design of high‐performance hydrogel electrolytes and demonstrates the potential of FAZIBs for practical wearable electronics.