Low-current-density stability of vanadium-based cathodes for aqueous zinc-ion batteries

Vanadium-based cathodes have received widespread attention in the field of aqueous zinc-ion batteries, presenting a promising prospect for stationary energy storage applications. However, the rapid capacity decay at low current densities has hampered their development. In particular, capacity stability at low current densities is a requisite in numerous practical applications, typically encompassing peak load regulation of the electricity grid, household energy storage systems, and uninterrupted power supplies. Despite possessing notably high specific capacities, vanadium-based materials exhibit severe instability at low current densities. Moreover, the issue of stabilizing electrode reactions at these densities for vanadium-based materials has been explored insufficiently in existing research. This review aims to investigate the matter of stability in vanadium-based materials at low current densities by concentrating on the mechanisms of capacity fading and optimization strategies. It proposes a comprehensive approach that includes electrolyte optimization, electrode modulation, and electrochemical operational conditions. Finally, we presented several crucial prospects for advancing the practical development of vanadiumbased aqueous zinc-ion batteries. (c) 2024 Science China Press. Published by Elsevier B.V. and Science China Press. All rights reserved.