Selective recycling lithium from spent lithium batteries using carbonate ester derived from electrolyte in hydrothermal environments

Recycling lithium from lithium -ion batteries (LIBs) and reducing electrolyte pollution are challenges for the sustainable development of the LIBs industry. Herein, we report a novel strategy for the selective recovery of lithium from spent LiMn0.5Co0.2Ni0.3O2 (NCM523) cathode materials via hydrothermal leaching using a carbonate ester derived from an electrolyte as the leaching agent. Lithium was leached via either the common linear or cyclic carbonate ester used in the electrolytes, and 98.58 % of the lithium was recovered with nearly 100 % selectivity using the carbonate ester mixture. Meanwhile, a lithium recovery purity above 99.8 % was achieved, which was attributed to the absence of the leaching of other metals. The lithium extraction using the actual recovered carbonate ester or different types of LIBs materials (LiMn2O4, LiCoO2, and various NCM cathode materials) is feasible. This work provides new inspiration for recycling lithium from spent LIBs in an eco-friendly and sustainable manner.