ZnF2‐Riched Inorganic/Organic Hybrid SEI: in situ‐Chemical Construction and Performance‐Improving Mechanism for Aqueous Zinc‐ion Batteries

Abstract Uncontrolled dendrites growth and serious parasitic reactions in aqueous electrolytes, greatly hinder the practical application of aqueous zinc‐ion battery. On the basis of in situ‐chemical construction and performance‐improving mechanism, multifunctional fluoroethylene carbonate (FEC) is introduced into aqueous electrolyte to construct a high‐quality and ZnF 2 ‐riched inorganic/organic hybrid SEI (ZHS) layer on Zn metal anode (ZMA) surface. Notably, FEC additive can regulate the solvated structure of Zn 2+ to reduce H 2 O molecules reactivity. Additionally, the ZHS layer with strong Zn 2+ affinity can avoid dendrites formation and hinder the direct contact between the electrolyte and anode. Therefore, the dendrites growth, Zn corrosion, and H 2 evolution reaction on ZMA in FEC‐included ZnSO 4 electrolyte are highly suppressed. Thus, ZMA in such electrolyte realize a long cycle life over 1000 h and deliver a stable coulombic efficiency of 99.1 % after 500 cycles.