Revealing the Triangular Entanglement of Hydrogen Bond Network via Kosmotropic Effect for Durable Aqueous Zinc‐Ion Batteries

Abstract Regulating the H‐bond network between H₂O molecules has been regarded as an effective strategy to reconfigure the chemical environment at the electrode/electrolyte interface (EEI), but the intrinsic relationship between hydrogen‐bond (H‐bond) network, solvation structure, and EEI in electrolyte remains unclear. To this end, three additives with the same carbon skeleton but different hydroxyl functional groups are chosen to unlock their triangular relationship. Experimental and theoretical calculations demonstrate that 2‐methyl‐1,3‐propanediol (MP) molecules bearing their strong kosmotropic effect and modest steric‐hindrance effect not only form a strong and stable H‐bonds network by breaking the original H‐bond network of electrolyte but also reconstruct the solvation structure of Zn²⁺, predominantly inhibiting the H₂O‐triggered side reactions. Meanwhile, the synergistic effect of the hydroxyl functional groups in the same direction on the MP molecules ensures stable adsorption at EEI, promoting uniform Zn²⁺ diffusion and deposition. Consequently, the assembled Zn||Zn symmetric cell provides 3000 h of cycle life (0.5 mA cm⁻², 0.5 mAh cm⁻²) in the ZnSO₄+MP electrolyte, and Zn||Cu asymmetric cell maintains a high CE of 99.41% after 1000 cycles at 1 mA cm⁻², 1 mAh cm⁻². The full cell with ZnSO₄+MP electrolyte exhibits excellent rate capability and satisfactory discharge‐specific capacity.