Zinc-ion coordinated inorganic silicone quasi-solid electrolyte for low self-discharge and stable zinc metal batteries

Aqueous zinc-ion batteries (ZIBs) have emerged as promising candidates for next-generation energy storage systems due to their inherent safety, cost-effectiveness, and high energy density. However, challenges such as hydrogen evolution reactions induced by active water in liquid electrolytes and the formation of zinc dendrites severely limit their practical application. To address the adverse effects of free water, various quasi-solid-state electrolytes are developed. In this study, a solid-liquid hybrid inorganic silica gel electrolyte (ISE) is synthesized via a facile sol-gel process. The ISE enables efficient zinc-ion transport through the synergistic interaction of a solid silica-oxygen framework and liquid water. Consequently, the ISE demonstrates an ionic conductivity of 1.39 × 10 –4 S cm –1 and exceptional long-term cycling stability, with over 800 h of long-term charge-discharge operation. Furthermore, the full cell retains 70 % of its capacity after 1800 cycles, with a low self-discharge rate and a capacity retention of up to 90 %.