A ternary cross-linked gel electrolyte with high mechanical strength and ionic conductivity for ultra-long-life reversible zinc deposition

Bottlenecks such as electrolyte leakage, zinc dendrite growth, and poor mechanical properties severely limit practical application of aqueous zinc ion batteries. To improve the cycle stability and reversibility of zinc deposition in zinc ion batteries, a ternary cross-linked gel electrolyte PCS composed of polyacrylamide, carboxymethyl cellulose and soluble starch was designed. The solid ternary cross-linked structure provides excellent mechanical properties of PCS gel. The interaction of polar groups with H2O and Zn2+ significantly reduced the activity of the mobilized water in PCS, inhibiting the occurrence of side reactions, and regulating the solvation structure of Zn2+. As a result, the cells with PCS have ultra-long-life reversible zinc deposition (stable cycling of Zn//Zn symmetric cells over 4900 h), high reversibility (coulombic efficiency of 99.5%) and high cycling stability (cycling stably for 1000 cycles).