Salt‐Bridged Miscibility Unlocks Hydrophobic Diluents to Engineer Anion‐Rich Solvation for Highly Reversible Zinc Batteries

Aqueous zinc batteries offer inherent safety and cost advantages, yet their further application is hindered by severe surface corrosion, H 2 evolution. While incorporating organic diluents is a common strategy to modify the electrolyte microenvironment, a fundamental dilemma exists: water‐miscible solvents usually have strong Zn 2+ binding energy, thereby increasing the Zn 2+ de‐solvation energy barrier, and even react with Zn metal, whereas inert, hydrophobic diluents fail to form a homogeneous phase. Here, we propose a salt‐bridged miscibility mechanism to break through this limitation. Guided by systematic screening, we demonstrate that specific Zn salts, notably Zn(OTf) 2 , act as efficient molecular bridges, dramatically lowering the miscibility barrier between H 2 O and hydrophobic diluents like tetrahydropyran (THP), thereby constructing thermodynamically stable and interface friendly homogeneous electrolyte. The inert THP disrupts the hydrogen bonding network between H 2 O molecules, broadens the electrochemical stability window, and participates in interface regulation. As a result, the Zn|Cu half cells employing this engineered inert electrolyte can maintain a high coulombic efficiency of 99.79% over 2000 cycles. And the full cells with HNVO cathode can retain remarkable stability over 30 000 cycles at 5 A g −1 . This work solves a fundamental trade‐off of hydrophobic diluents for future electrolyte engineering.