Technology and principle on preferentially selective lithium extraction for spent ternary lithium batteries: A review

[Display omitted] •Progress on preferentially selective lithium extraction from active cathode materials of spent ternary lithium batteries are detail reviewed.•The reaction principles and mechanisms of the different Li recovery methods are discussed.•Unravel the technical essence and underlying challenges for LIB recycling.•Emphasize the importance of priority recycling Li to the future LIB recovery. Given the significance of resource conservation and environmental preservation inherent in spent lithium-ion batteries, the effective recovery and use of valuable metal components of spent lithium-ion batteries have become an important measure to alleviate problems. Preferential selective Li extraction has attracted attention for tackling the shortage of Li resources. Based on summarizing the four stages of preliminary separation in the pre-treatment process of spent ternary lithium batteries, the reaction principles and mechanisms of the recovery methods, such as hydrometallurgy, combined pyro-hydrometallurgical processes, membrane separation, and biometallurgy, are further explored, and the advantages and disadvantages of the various methods are evaluated. Through the analysis of the principle, reaction process and results of recovering lithium methods can provide a few directions for scholars’ subsequent research. It is prudent to advocate for a transition towards a safe, environmentally sound, and efficient approach in recycling and utilizing cathode materials from spent ternary lithium batteries.