Hydrated Eutectic Electrolyte Regulating Hydrogen‐Bond Network toward Wide‐Temperature Adaptability for Zinc‐Metal Batteries

Abstract Dendrite growth and interfacial side reactions often degrade the performance of zinc‐ion batteries, hindering their practical application in renewable energy storage, particularly under harsh conditions. Herein, a hydrated eutectic electrolyte design through co‐solvent and additive engineering is proposed using ethylene glycol (EG) and trace choline bromide (CB) for a typical ZnSO 4 electrolyte. Molecular dynamics simulations and spectroscopic analyses demonstrate that H 2 O molecules confined in Zn 2+ solvation shells are regulated through hydrogen‐bonding coordination. More importantly, EG co‐solvent effectively suppresses the activity of free H 2 O and extends the operation‐temperature range of the electrolyte. Besides, the preferential adsorption of CB additive on Zn‐anode surface not only guides zinc deposition along (002) plane with improved uniformity, but also participates in constructing heterogeneous organic‐inorganic solid‐electrolyte interphase layer. The designed ZSO‐EG‐CB electrolyte endows Zn||Zn symmetric cell with an exceptional lifespan exceeding 8500 h at 5 mA cm −2 , meanwhile supports the Zn||NVO full cell with excellent rate capability and high cycling stability within wide‐temperature tolerance (−20 to 60 °C). This work establishes a dual‐regulation paradigm through synergistic solvation environment modulation and interface engineering, providing a promising strategy for high‐performance electrolytes in wide‐range temperature Zn‐metal batteries.