Application of wheat starch-acrylamide dual-crosslinked hydrogel in flexible zinc-air batteries

A dual-crosslinking strategy, in which wheat starch and acrylamide was used to construct a low-cost and high-performance gel electrolyte, was proposed to overcome the challenges of high cost, poor water retention, and interfacial instability of electrolytes in flexible zinc-air batteries., Material characterization, electrochemical testing, and quantum chemical calculations were employed to evaluate its structural and electrochemical properties and to elucidate the mechanisms of performance enhancement. The results demonstrate that, in comparison with polyacrylamide gel, the developed gel exhibits a water retention rate of 81.7% after 12 hours, representing a 16% improvement; a fracture strain of 135%, indicating an 81% enhancement; an ionic conductivity of 375 mS/cm, reflecting a 69% increase; and a discharge power density of 175 mW/cm², showing a 48% rise. Furthermore, the cycling stability of the assembled flexible zinc-air battery exceeds 45 hours, indicating a twofold enhancement in operational lifespan. This dual-crosslinking strategy, which forms continuous hydrophilic ion channels and enhances interfacial wettability, significantly improves water retention, mechanical strength, ionic conductivity, and electrochemical stability, thereby offering an optimization solution for the development of flexible zinc-air batteries.