Engineering Spatiotemporally‐Resolved Hydrogen‐Bond Networks for Decoupled H + /Zn 2+ Transport Toward Durable Low‐Temperature Aqueous Zinc‐Ion Batteries

ABSTRACT The performance of aqueous zinc‐ion batteries is limited by the coupled transport of protons (H + ) and Zn 2+ due to extensive hydrogen‐bond (H‐bond) networks in conventional electrolytes. To achieve the decoupling of this detrimental interplay, we establish a spatiotemporal H‐bond network regulation strategy via a meticulously designed choline chloride/glycerol‐based hydrated deep eutectic electrolyte (HDEE). Spatially, the HDEE reduces H‐bond network connectivity, decreasing average cluster size from 843 to 243 molecules, thereby weakening the long‐range pathways for Grotthuss proton hopping. Temporally, a system‐optimized H‐bond lifetime of 11.2 ps suppresses rapid H + transfer while maintaining sufficient dynamic flexibility essential for Zn 2+ solvation‐sheath reorganization. Such synergistic regulation further tailors the primary solvation structure of Zn 2+ , lowering its desolvation energy barrier. As a result, the HDEE effectively suppresses hydrogen evolution and corrosion, enabling uniform, dendrite‐ suppressed zinc deposition. The Zn//Zn symmetric cell achieves stable cycling for about 6400 hours at −25°C. Moreover, the Zn//I 2 full battery retains 93.6% capacity after 20,000 cycles at 5 A g −1 , accompanied by the effective suppression of the polyiodide shuttle effect. This work highlights network connectivity and H‐bond lifetime as useful descriptors for correlating H‐bond‐network characteristics with ion‐transport behavior, offering a promising design principle for advanced aqueous batteries.