Synergistic modulation of alkaline aluminum-air battery based on localized water-in-salt electrolyte towards anodic self-corrosion

Abstract

A long-term hurdle for Al-air batteries is the severe open-circuit corrosion, irreversibly self-discharging more than 80% per month depending on the battery design. In this work, we introduce an ionic liquid-ethylene glycol system as a local water-in-salt electrolyte to modify the conventional aqueous solution. At the same time, synergistic effect between morin and ionic liquid is employed to further reduce the salt component, as well as improving the performance. Experiments such as electrochemical test, surface analysis and theoretical calculations prove that the additives can modulate the anodic interface and restrain the free water molecules through hydrogen bond. Thus, Al-6061 anode suffers low parasitic corrosion rate and gains stable surface. Furthermore, the performance of assembled aluminum air battery is greatly improved with an excellent specific capacity of 2010 mAh/g, reliable cycle stability and anode utilization.