Review on Multivalent Rechargeable Metal-Organic Batteries

Rechargeable multivalent-ion batteries are considered as sustainable energy storage solutions that can supplement the current lithium-ion technology. Their large-scale application is however hindered by the lack of high-capacity cathode materials. Organic electrode materials (OEMs) in metal-organic batteries (MOBs) offer unique opportunities thanks to their structure diversity and tunability. Unfortunately, their potential is still not fulfilled as a result of a series of challenges. Here, we present an overview of recent progresses in enhancing the electrochemical performances of OEMs in MOBs. We first discuss the electrochemical performance and charge storage mechanism of different types of OEMs in MOBs, including conductive polymers, carbonyl and organosulfur compounds, and some other organic materials. This is then followed by the discussion on different strategies employed to improve the performances of MOBs through structure engineering, polymerization, hybridization, and amorphization of OEMs. Finally, a short perspective is provided for the possible future development of OEMs in MOBs.