Electrochemical technology to drive spent lithium-ion batteries (LIBs) recycling: recent progress, and prospects

The widespread use of lithium-ion batteries (LIBs) in recent years has led to a marked increase in the quantity of spent batteries, resulting in critical global technical challenges in terms of resource scarcity and environmental impact. Therefore, efficient and eco-friendly recycling methods for these batteries are needed. The recycling methods for spent LIBs include hydrometallurgy, pyrometallurgy, solid-phase regeneration, and electrochemical methods. Compared to other recycling methods, electrochemical methods offer high ion selectivity and environmental friendliness. Assembling research on the recycling and reutilization of spent LIBs, with a focus on the various electrochemical techniques that can enhance these processes, is essential. A thorough analysis of the characteristics and evolution of these methods remains crucial to advancing the field of electrochemical technology in battery recycling. This review first discussed the necessity of recycling spent LIBs from multiple perspectives and briefly introduced the main pyrometallurgical and hydrometallurgical recycling technologies, analyzing their advantages and disadvantages. Moreover, we comprehensively summarized the current applications of electrochemical technology in the recycling of spent LIBs, including pretreatment, leaching, element separation, and regeneration. Then, we analyzed the characteristics and advantages of different electrochemical techniques in the LIB recycling process and discussed the obstacles encountered in the application of electrochemical technology and their solutions. Finally, a comparison between electrochemical technology and traditional recycling processes was provided, highlighting the potential advantages of electrochemical technology in reducing recycling costs and minimizing waste emissions.