Research progress on the separation of cathode materials from metal current collectors of spent lithium-ion batteries

With wide applications of lithium-ion batteries in the field of electronic equipment/devices, the recycling and reutilization of spent lithium-ion batteries has become a popular research topic for the reutilization of secondary resources. Compared with the traditional metallurgical recovery method, the direct repair of cathode materials simplifies the recycling process and has good application prospects. The efficient stripping of the cathode material and metal current collector (aluminum foil) in the pretreatment process is a key part of the direct recovery of cathode materials. In this work, the current research status and advantages and disadvantages of physical (mechanical separation, organic solvent separation, centrifugal separation, electrostatic separation, water phase separation) and chemical methods (thermal treatment, electrolysis, acid and alkaline treatments, advanced oxidation, deep eutectic solvents) for stripping cathode materials and metal collectors from spent lithium-ion batteries are reviewed, respectively, and the prospects for the application of the emerging stripping methods are outlooked, which provides an important reference for the efficient and cost-effective pretreatment of spent lithium-ion batteries.