A novel strategy of lithium recycling from spent lithium-ion batteries using imidazolium ionic liquid

Abstract

In light of the increasing demand for environmental protection and energy conservation, the recovery of highly valuable metals, such as Li, Co, and Ni, from spent lithium-ion batteries (LIBs) has attracted widespread attention. Most conventional recycling strategies, however, suffer from a lack of lithium recycling, although they display high efficiency in the recovery of Co and Ni. In this work, we report an efficient extraction process of lithium from the spent LIBs by using a functional imidazolium ionic liquid. The extraction efficiency can be reached to 92.5% after a three-stage extraction, while the extraction efficiency of Ni-Co-Mn is less than 4.0%. The new process shows a high selectivity of lithium ion. FTIR spectroscopy and ultraviolet are utilized to characterize the variations in the functional groups during extraction to reveal that the possible extraction mechanism is cation exchange. The results of this work provide an effective and sustainable strategy of lithium recycling from spent LIBs.