Recent progress on the recycling technology of Li-ion batteries

Lithium-ion batteries (LIBs) have been widely applied in portable electronic devices and electric vehicles. With the booming of the respective markets, a huge quantity of spent LIBs that typically use either LiFePO4 or LiNixCoyMnzO2 cathode materials will be produced in the very near future, imposing significant pressure for the development of suitable disposal/recycling technologies, in terms of both environmental protection and resource reclaiming. In this review, we firstly do a comprehensive summary of the-state-of-art technologies to recycle LiNixCoyMnzO2 and LiFePO4-based LIBs, in the aspects of pretreatment, hydrometallurgical recycling, and direct regeneration of the cathode materials. This closed-loop strategy for cycling cathode materials has been regarded as an ideal approach considering its economic benefit and environmental friendliness. Afterward, as for the exhausted anode materials, we focus on the utilization of exhausted anode materials to obtain other functional materials, such as graphene. Finally, the existing challenges in recycling the LiFePO4 and LiNixCoyMnzO2 cathodes and graphite anodes for industrial-scale application are discussed in detail; and the possible strategies for these issues are proposed. We expect this review can provide a roadmap towards better technologies for recycling LIBs, shed light on the future development of novel battery recycling technologies to promote the environmental benignity and economic viability of the battery industry and pave way for the large-scale application of LIBs in industrial fields in the near future.