Development of anion conductive gel polymer electrolytes with high ion conductivity and long-term stability for rechargeable zinc air battery

Abstract

Rechargeable zinc air batteries (r-ZABs) are expected to be the next generation secondary batteries due to their higher capacities than lithium ion batteries. However, they have not yet been put into practical applications because of the solvent evaporation and dendritic growth, resulting in low charge–discharge cycle stabilities in r-ZABs using conventional aqueous electrolytes. In this study, a novel anion-conductive gel polymer electrolyte (GPE) membrane, consisting of a crosslinked network polymer bearing anion exchange groups, hydroxide ion-conductive ionic liquid (IL), and electrospun polymer nanofibers, was developed. This GPE(IL) showed high cycling stability over 400 charge–discharge r-ZAB battery cycles, with liquid volatilization suppression, reduced zincate ion diffusion, and improved tolerance to CO2 exposure as demonstrated through solid-state 13C NMR, all contributing to this greatly improved r-ZAB performance.Graphical abstract