Recent advances and challenges of cathode materials in aqueous rechargeable zinc-ion batteries

Abstract

Aqueous Zn-ion battery (AZIB) is a new type of secondary battery developed in recent years. It has the advantages of high energy density, high power density, efficient and safe discharge process, non-toxic and cheap battery materials, simple preparation process, etc., and has high application prospects in emerging large-scale energy storage fields such as electric vehicles and energy storage grids. Currently, one of the main factors hindering the further development of AZIBs batteries is the lack of suitable cathode materials. This article briefly introduces the advantages and energy storage mechanisms of aqueous zinc-ion batteries. Based on the crucial role of cathode materials in AZIBs, several common cathode materials (such as manganese-based compounds, vanadium-based compounds, nickel/cobalt-based compounds, and lithium/sodium intercalated compounds) are reviewed, and strategies to improve their conductivity and cycling stability are summarized, focusing on modification strategies such as structural regulation, nanoengineering, doping modification, and compounding with high-conductivity materials. The article also points out the key development directions for cathode materials of AZIBs in the future.