Electrostatic Potential-Dominated Weak Solvation Chemistry for Synergistic Optimization of V₂O₅ Cathode and Zn Anode

Practical aqueous zinc-ion batteries face severe challenges from cathodic dissolution and anodic dendrite growth. Herein, we report a novel electrostatic potential-dominated weakly solvated electrolyte that correlates molecular charge anisotropy with both solvation thermodynamics and interfacial passivation kinetics. By regulating the electrostatic force among Zn²⁺, H₂O, and weak solvent, the attack ability of free water on vanadium oxide is efficiently reduced, and the vanadium dissolution is effectively prohibited. Simultaneously, the modified solvating structure induces a dense and inorganic-rich solid electrolyte interface, promoting uniform zinc deposition and suppressing side reactions. Benefiting from such synergistic optimization, the developed zinc-ion battery achieves a high capacity of 410 mAh g^-1 and maintains 80% of the capacity after 650 cycles at 0.5 A g^-1. Stable Ah-level pouch cell with high energy density (138 Wh kg^-1, based on electrode mass; 36.3 Wh kg^-1, based on full cell) is also achieved, paving a promising way for practical applications.