Weak-hydrogen-bond continuum via coordination-induced intramolecular strain for low-temperature Zn-ion batteries

Ideal electrolytes for low-temperature-resistant aqueous zinc-ion batteries should promote rapid ion desolvation while stabilizing interfacial reactions. Existing research generally introduces additive molecules for optimizing local coordination environment to inhibit H 2 O crystallization; the strong hydrogen bond (HB) effect between co-solvents still exists, and uncoordinated polar groups act as acceptors/donors to induce uneven group coordination and the formation of new strong HB networks. Herein, we propose an electrolyte design strategy with a coordination-induced mechanism to address the long-standing challenges of slow low-temperature kinetics and irregular dendrites in aqueous zinc-ion batteries. By introducing low-carbon polyols to optimize the global solvation structure, low-temperature ice crystallization through intramolecular strain is mitigated, promoting the interaction between non-coordinating solvents to shift from strong HB (O-H:O*, 30 kJ/mol) to weak HB (C-H:O*, 5 kJ/mol), which enables dynamic salt-water-organic cosolvent ternary interaction, promoting rapid Zn 2+ reaction kinetics and stabilizing interfacial reactions. Both experimental and theoretical analyses confirm the effectiveness of the present strategy, which enables low-carbon-polyol-based electrolyte to exhibit a high capacity of 65.13 mAh/g at −25 °C (1 A/g) and a capacity retention of ~95% after 600 cycles.