Pyrometallurgical options for recycling spent lithium-ion batteries: A comprehensive review

Lithium-ion batteries (LIBs) have attracted increasing attention for electrical energy storage applications in recent years due to their excellent electrochemical performance. The unprecedented growth trajectory in lithium-ion battery manufacturing perpetuated by the inception of electric vehicles (EV) results in a vast amount of spent LIBs reaching their end of life (EOL). From the perspective of resource circulation, procurement, and sustainability with an insight into the circular economy, an effective recycling system must be developed to recycle the spent LIBs. This paper provides a comprehensive overview of the current status of pyrometallurgical options for recycling spent LIBs. In particular, this study summarizes the thermal pretreatment methods used to recover the active cathode material and then discusses the developed extractive pyrometallurgical options for recycling spent LIBs. A summary is presented on some recent examples of laboratory and industrial-scale recycling processes to demonstrate the practical applications of pyrometallurgical options for recycling. Finally, the review sheds light on the battery recycling legislation, and challenges and future outlook for recycling LIBs are also discussed.