DMSO-Based Organohydrogel Electrolyte Suppressing Zinc Dendrites for Long-Cycling Zinc-Air Batteries

The rapid growth of flexible wearable electronics has driven the need for lightweight, high-energy-density energy storage solutions. Flexible zinc-air batteries (FZABs) have emerged as promising candidates for next-generation power sources in wearable devices. However, one of the key challenges is the development of high-performance hydrogel electrolytes that can support the efficiency and flexibility required for these applications. Traditional hydrogel electrolytes often suffer from zinc-dendrite-induced corrosion, which limits their practical use. In this study, an organohydrogel electrolyte was developed by incorporating dimethyl sulfoxide (DMSO) into a poly(acrylic acid)-butyl acrylate (PAB) copolymer. The introduction of DMSO significantly enhances the solvation sheath of zinc ions, facilitating uniform zinc ion deposition and effectively suppressing dendrite growth. Moreover, the DMSO-modified electrolyte significantly improves the antifreeze properties and electrochemical performance of the zinc-air battery, expanding its operational temperature range to as low as −40 °C with stable cycling. Compared to traditional hydrogel electrolytes, the optimized organohydrogel electrolyte enables flexible zinc-air batteries to achieve a stable open-circuit voltage of 1.39 V, an energy efficiency of 68.6%, and a cycle life of over 70 h. Notably, a superior specific capacity of 721.21 mAh·g–1 was maintained even at −40 °C. Additionally, the flexible zinc-air batteries demonstrated robust performance under mechanical deformation, such as bending up to 90° and powering light-emitting diodes (LEDs) in various configurations, showcasing their substantial potential for practical applications in wearable devices.