Current Status and Future Prospects on Upcycling Spent Lithium-Ion Batteries for the Preparation of Electrocatalysts

Spent lithium-ion batteries (LIBs), which typically contain valuable transition metals such as nickel, cobalt, and manganese as well as toxic organic electrolytes, pose significant risks to human health and the environment. Remarkable progress has been made in developing efficient, cost-effective, and environmentally friendly processes for upcycling spent LIBs, which has primarily concentrated on the recovery of critical metal resources that can be reutilized for the production of various functional materials such as electrocatalysts. Spent LIBs contain significant quantities of transition metals at the cathodes and graphite at the anodes, which possess considerable potential for upgrading into electrocatalysts suitable for a wide range of electrochemical reactions, including the oxygen evolution reaction (OER), oxygen reduction reaction (ORR), and hydrogen evolution reaction (HER). This review offers a comprehensive summary of emerging strategies for upcycling waste LIBs into electrocatalysts along with future prospects for their high-value utilizations.