Hybrid Co‐Solvent‐Induced High‐Entropy Electrolyte: Regulating of Hydrated Zn²⁺ Solvation Structures for Excellent Reversibility and Wide Temperature Adaptability

Abstract As a new generation of lithium‐ion battery alternative, aqueous zinc (Zn) ion batteries (ZIBs) garner tremendous interests for future energy storage application owing to their inherent incombustible, nontoxic, and low‐cost features. However, their practical utilization is hampered by the electrolyte freezing at subzero conditions. In this study, a novel high‐entropy (HE) electrolyte fabricated is presented with hybrid solvents to mitigate electrolyte freezing at low temperatures, restrain calendar corrosion, and boost Zn‐ion transfer kinetics. Specifically, the isovolumetric combined ethyl acetate, ethylene glycol, and dimethyl sulfoxide as solvent components not only induce a reconfiguration of hydrogen bonding, but also alter the solvation sheath of Zn ions within the HE electrolyte environment. This synergistic coupling of hybrid co‐solvents effectively harnesses the features of individual solvent additive and facilitates the remarkable advantages on cycling reversibility, especially in the low‐temperature conditions. Benefiting from the anti‐freezing and solvation structure regulation features, Zn symmetrical batteries equipped with HE electrolytes can work over 2500 h in low zinc salt concentration (1 m) at various temperatures. This work provides a facile modulation strategy to achieve the HE electrolyte, promoting the practical application and commercialization of advanced ZIBs with wide‐temperature adaptability.