Three-dimensional scaffold-supported hydrogel electrolytes with integrated high conductivity and stability for robust zinc-ion batteries

Hydrogel electrolytes (HGEs) have emerged as promising electrolytes for zinc-ion batteries (ZIBs), owing to their favorable mechanical strength, ionic conductivity, and interfacial stability. However, simultaneously achieving these mutually conflicting properties remains a key issue that hinders their rapid development. Herein, we propose a molecular-scale strategy to precisely balance these mutually conflicting properties in HGEs using sucrose and choline chloride. Our findings reveal that the synergistically modified HGE, achieving a high hydrogen production inhibition rate of 97.2%, high ionic conductivity of 17.71 mS·cm⁻¹, high mechanical properties (strength of 278.07 kPa, elongation of 463.62%), enabling the Zn anode to reach an average Coulombic efficiency (CE) of 99.16% over 700 cycles and maintain highly reversible cycling for up to 1300 h at a high current density of 5 mA·cm⁻². This study presents a promising strategy for developing a green, high-performance HGE, which is expected to accelerate the practical implementation of ZIBs.