A green and efficient combination process for recycling spent lithium-ion batteries

Considering the growing number of spent lithium-ion batteries (LIBs), it is of great interest to recover valuable metals in an environmentally friendly manner, but this remains a challenge. A pretreatment-deep eutectic solvent (DES) tandem recovery process was developed to recycle various metals from spent LIBs selectively. The pre-treatment step allows the recovery of graphite, diaphragm, copper, and aluminum foil. Combined with the leaching separation process based on DES synthesized from betaine hydrochloride (BeCl) and ethylene glycol (EG), it could exploit the difference in transition metal ion coordination, thus selectively leaching and separating cobalt (Co), manganese (Mn), and nickel (Ni) from the cathode material. This method can comprehensively recover electrode materials, thereby solving the problem of environmental pollution and resource wastage of spent LIBs and realizing the sustainability of the new energy industry.