Challenges and perspectives towards direct regeneration of spent LiFePO4 cathode

Recycling of spent lithium-ion batteries (LIBs) has emerged as an inevitable trend in promoting environmental sustainability and resource conservation. Lithium iron phosphate (LiFePO4 or LFP) battery, renowned for its unique stability and favorable price, has been the predominant focus for lithium-ion battery manufacturers, consequently resulting in a surge in the number of spent LIBs. In view of the failure mechanism, the direct regeneration technology presents a potential strategy for the closed-loop recycling of LFP. The aim is to retain the high added value and revitalize optimal state of the spent cathode materials through a non-destructive process that maximizes efficiency and ensures desirable profits. Hence, the existing technical challenges and recent progress in the separation pretreatment are reviewed and summarized. Subsequently, the current direct regeneration methods and advanced upcycling techniques for spent LFP cathode are outlined, along with an appraisal of their respective advantages and disadvantage. Specifically, a comprehensive analysis of environmental and economic benefits derived from three presentative examples is highlighted compared to traditional metallurgy process. The review also aims to provide an overview on direct regeneration of spent LFP cathode, making it favorable for further industry adoption.