Synergy of In Situ Heterogeneous Interphases with Hydrogen Bond Reconstruction Enabling Highly Reversible Zn Anode at −40 °C

Abstract Aqueous Zn 2+ ion batteries (AZIBs) are considered promising candidates for large‐scale energy storage systems. However, the critical technical bottlenecks, including Zn dendrite, corrosion reactions, and poor low‐temperature performance, significantly impede their commercialization. Here, γ‐valerolactone (γ‐GVL), a bioactive polar biomass‐based green solvent derived from lignocellulose, is introduced into electrolyte as a co‐solvent to improve the electrochemical stability of Zn anode and enhance its low‐temperature cycling performance. The non‐toxic γ‐GVL, serving as a strong hydrogen‐bonding ligand, coordinates with H 2 O to reconstruct the electrolyte's hydrogen bond network, broadening the electrochemical stability window and enhancing the anti‐frost properties of aqueous electrolytes. Moreover, γ‐GVL facilitates in situ formation of a heterogeneous solid‐electrolyte interphase (SEI) composed of ZnF 2 and ZnS inorganic components. The heterogeneous interphases maintain superior ionic conductivity for Zn 2+ transportation and hydrophobicity for H 2 O repulsion, synergistically enabling highly stable and dendrite‐free Zn deposition. Consequently, Zn||Zn cells exhibit improved cycling performance across a wide temperature range, achieving an extended cycle life of 5060 h at 25 °C and 2300 h at −40 °C. Zn||VO 2 full cells show enhanced low‐temperature cyclability, retaining 97.0% capacity after 300 cycles at −20 °C, demonstrating substantial potential for advancing the commercialization of low‐temperature aqueous electrolytes.