Zincophobic Electrolyte Achieves Highly Reversible Zinc‐Ion Batteries

Zinc metal batteries show tremendous applications in wide‐scale storages still impeded by aqueous electrolytes corrosion and interfacial water splitting reaction. Herein, a zincophobic electrolyte containing succinonitrile (SN) additive is proposed, the SN electrolyte shows a lower affinity for zinc but a stronger affinity for solid‐state interphase (SEI). In the SN electrolyte, zinc hydroxide sulfate (ZHS) is more inclined to accumulate horizontally, forming a dense SEI protective layer on the surface of the Zn anode, effectively slowing down the corrosion of Zn and dendrite growth. The zincophobic SN electrolyte enables excellent performance: zinc plating/stripping Coulombic efficiency of 99.71% for an average of 400 cycles; stable cycles in a symmetric cell for 4000 h (0.9% zinc utilization) and 325 h (86.1% zinc utilization). The soft pack battery using limited zinc delivers maximum energy density of 57.0 Wh kg−1 (based on mass loading of cathode materials and anode materials). Such a simple additive strategy provides a theoretical reference for zinc chemistry in a mild electrolyte environment in practical applications. Introduction of succinonitrile molecules into the electrolyte to construct a zincophobic electrolyte can change the free energy of the anode surface. The zincophobic electrolyte has lower affinity for Zn metal, so that it can slow down the occurrence of hydrogen evolution reaction and reduce corrosion caused by the interface water.