A Temperature Self‐Adaptive Electrolyte for Wide‐Temperature Aqueous Zinc‐Ion Batteries

The advancement of aqueous zinc‐ion batteries (AZIBs) is often hampered by the dendritic zinc growth and the parasitic side reactions between the zinc anode and the aqueous electrolyte, especially under extreme temperature conditions. This study unveils the performance decay mechanism of zinc anodes in harsh environments, characterized by “dead zinc” at low temperatures and aggravated hydrogen evolution and adverse by‐products at elevated temperatures. To address these issues, a temperature self‐adaptive electrolyte (TSAE), founded on the competitive coordination principle of co‐solvent and anions, is introduced. This electrolyte exhibits a dynamic solvation capability, engendering an inorganic‐rich solid electrolyte interface (SEI) at low temperatures while an organic alkyl ether‐ and alkyl carbonate‐containing SEI at elevated temperatures. The self‐adaptability of the electrolyte significantly enhances the performance of the zinc anode across a broad temperature range. A Zn//Zn symmetrical cell, based on the TSAE, showcases reversible plating/stripping exceeding 16 800 h (>700 d) at room temperature under 1 mA cm−2 and 1 mAh cm−2, setting a record of lifespan. Furthermore, the TSAE enables stable operation of the zinc full batteries across an ultrawide temperature range of −35 to 75 °C. This work illuminates a pathway for optimizing AZIBs under extreme temperatures by fine‐tuning the interfacial chemistry. This study elucidates the failure mechanisms of zinc anodes in aqueous electrolytes under high‐ and low‐temperature conditions. By manipulating the competitive relationship between solvents and anions in the electrolyte, a temperature self‐adaptive electrolyte is devised and fabricated to enable the superior operation of zinc anodes within the temperature range of −35 to 75 °C.