High Interfacial Stability Eutectic Gel Electrolyte for High‐Temperature Rechargeable Zinc Metal Batteries

Rechargeable zinc metal batteries (RZMBs) have become promising energy storage systems due to their high safety and low cost. However, poor cycle stability caused by parasitic side reactions (such as hydrogen evolution and corrosion) and dendrite growth at the zinc anode/electrolyte interface, especially the deterioration at high temperatures, seriously restrict their application. Herein, a new eutectic gel electrolyte was developed, which realizes the regulation of Zn 2+ solvated structure and the coordinated strengthening of interface stability by combining the deep eutectic solvent with the polymer matrix. Eutectic gel electrolyte not only has the advantages of low volatility, wide electrochemical window, and high thermal stability of eutectic solvents, but also further inhibits side reactions and uniformizes ion transport through the gel network. The results show that eutectic gel electrolyte can effectively inhibit zinc dendrites growth, reduce interfacial hydrogen evolution, corrosion, and maintain excellent stability at high temperatures. The symmetrical cell based on this electrolyte achieves stable cycles of more than 2100 h at a current density of 0.5 mA cm −2 , with an average Coulombic efficiency of up to 99.08%. More importantly, even at high temperatures 50°C, the zinc plating/stripping of more than 2100 h can be maintained, alleviating the serious internal side effects of Zn//nitrogen‐doped hydration V 2 O 5 batteries at high temperature. This work provides a new strategy for designing highly stable and thermally resistant electrolytes for RZMBs, offering a promising pathway toward their practical implementation.