All-in-One Polymer Gel Electrolyte towards High-Efficiency and Stable Fiber Zinc-Air Battery.

Abstract

Fiber zinc-air batteries are explored as promising power systems for wearable and portable electronic devices due to their intrinsic safety and the use of ambient oxygen as cathode material. However, challenges such as limited zinc anode reversibility and sluggish cathode reaction kinetics result in poor cycling stability and low energy efficiency. To address these challenges, we design a polydopamine-based all-in-one gel electrolyte (PAGE) that simultaneously regulates the reversibility of zinc anodes and the kinetics of air cathodes through polydopamine interfacial and redox chemistry, respectively. The intrinsic catechol and carboxylate groups in PAGE regulate the transport and solvation structure of Zn2+, facilitating dendrite-free zinc deposition with a lamellar stacking morphology. Additionally, the oxidation of redox-active catechol groups in PAGE replaces the sluggish oxygen evolution reaction on the air cathode and reduces the energy barrier for charging, enabling fiber zinc-air batteries to achieve a significantly improved energy efficiency of 95% and a longer lifespan of 40 hours. Further integration into self-powered electronic textiles underscores its potential for next-generation wearable systems.