Abstract: In recent years, with the rise and rapid development of new energy vehicles (EV), it is expected that a large number of lithium batteries will be scraped and disposed after 2025. Recycling valuable metals from spent lithium ion batteries can effectively reduce the environmental pollution of spent lithium batteries and realize the recycling of its resources, reducing the supply and demand conflict caused by the surge in the use of energy metals such as Li, Co and Ni. Selective lithium extraction from spent lithium-ion battery cathode materials can achieve short-flow recovery of lithium resources, and is conducive to the subsequent separation and extraction of cobalt and nickel high-value energy metals. Therefore, in recent years, the research on the selective extraction of lithium from spent lithium-ion batteries has attracted a lot of attentions. In this paper, we systematically sorted out the current research on selective lithium extraction by various recycling systems, including pyro-metallurgical processes such as high temperature smelting, thermal reduction and salting and roasting, and hydrometallurgical technologies of inorganic acid leaching, organic acid leaching, oxidative leaching et al. The advantages and disadvantages of different processes are also discussed in terms of environmental protection, leaching efficiency, energy consumption, and process feasibility. Finally, the development of efficient recovery of lithium from used lithium-ion batteries is prospected.