Green closed-loop regeneration of ternary cathode materials from spent lithium-ion batteries through deep eutectic solvent

The increasing lithium-ion batteries (LIBs) market causes concerns about environmental issues and the mining of the earth's metallic minerals. The harmless treatment of the spent LIBs and the effective recovery of scarce metal resources are gradually given high priority worldwide. In this article, p-toluenesulfonic acid-based deep eutectic solvents (DESs) are prepared to leach metal components from spent ternary LIBs. And the ternary LiNi0.5Co0.2Mn0.3O2 material is regenerated through the co-precipitation method and high-temperature solid phase method. The results show that 97.96% of Li, 99.46% of Ni, 100% of Co, and 100% of Mn can be leached out again under the optimum conditions. The synthesized ternary material possesses an excellent reversible capacity (139.0 mAh center dot g(-1) at 0.5 C) and an adequate long-cycle stability (123.6 mAh center dot g(-1) after 100 cycles). This work provides an efficient and clean approach to recycling spent LIBs and has great potential application in the field of battery sustainability.