Novel targetedly extracting lithium: An environmental-friendly controlled chlorinating technology and mechanism of spent lithium ion batteries recovery.

A targeted extraction technology for recycling lithium from spent lithium transition metal oxides (LTMO) type batteries is developed in this paper. The chlorinating technology with ammonium chloride as the only additive is employed and controlled to selectively extract lithium. High lithium extraction rate with a low selectivity was first obtained at non-controlled chlorinating conditions. During this process, it was found that the reducing driving force (RDF) played a vital role in metals extraction. Once RDF was controlled at a low level, lithium elements could be targetedly extracted out while other metal elements still remained in the residues. The results showed that 91.73% lithium elements were leached out with a selectivity of 90.04% at the optimal conditions. Further, the mechanism was proposed to explain the release behavior of metals from cathode materials from the perspective of extracting driving force. These principles also offer inspiration for metal selective extraction fields such as metallurgy and recovery of complex systems including multiple metals.