Direct Regenerating Cathode Materials from Spent Lithium-Ion Batteries

Recycling cathode materials from spent lithium-ion batteries (LIBs) is critical to a sustainable society as it will relief valuable but scarce recourse crises and reduce environment burdens simultaneously. Different from conventional hydrometallurgical and pyrometallurgical recycling methods, direct regeneration relies on non-destructive cathode-to-cathode mode, and therefore, more time and energy-saving along with an increased economic return and reduced CO2 footprint. This review retrospects the history of direct regeneration and discusses state-of-the-art development. The reported methods, including high-temperature solid-state, hydrothermal/ionothermal, molten salt thermochemistry, and electrochemical method, are comparatively introduced, targeting at illustrating their underlying regeneration mechanism and applicability. Further, representative repairing and upcycling studies on wide-applied cathodes, including LiCoO2 (LCO), ternary oxides, LiFePO4 (LFP), and LiMn2O4 (LMO), are presented, with an emphasis on milestone cases. Despite these achievements, there remain several critical issues that shall be addressed before the commercialization of the mentioned direct regeneration methods. Direct regeneration method takes a shortcut to obtain cathodes with performance near to, same as, or even superb to that of the cathode synthesized from the normal routes, without the disruption and reformation of crystal structure. Here is an overview of directly regenerating cathode materials from spent lithium-ion batteries and a summary of representative works in this field.image

Automated summary

Recycling cathode materials from spent lithium-ion batteries is crucial for sustainability. Direct regeneration methods offer a non-destructive and efficient way to obtain high-performance cathodes, reducing energy consumption and carbon footprint. This review discusses the development of direct regeneration and introduces various methods and studies on repairing and upgrading cathodes.