Advances and challenges in graphite recycling from spent lithium-ion batteries

Abstract

With the continuous growth of global energy demand, the demand for graphite as an anode material for lithium-ion batteries (LIBs) has increased significantly. However, the large volume of end-of-life LIBs generates substantial amounts of retired graphite, which not only poses potential environmental risks but also raises challenges for strategic resource security, making its standardized management an urgent issue. This review focuses on the recycling and reuse of graphite from retired LIBs, systematically summarizing the core stages of the recovery process, including battery disassembly, graphite separation and purification, and strategies for restoring the performance of regenerated graphite. Key technologies, such as mechanical disassembly, hydrometallurgical/pyrometallurgical treatment, acid leaching, graphitization, flash joule heating, microwave treatment, and carbon coating, are analyzed in terms of their advantages and limitations, with discussion on effective approaches to enhance the electrochemical performance, structural repair, and cycling stability of regenerated graphite. Despite significant progress in graphite recycling and regeneration, several research gaps remain, such as the unclear quantitative relationship between defect repair efficiency and energy input during regeneration, which hinders precise process control, and the heterogeneity of retired graphite from different sources, which limits the adaptability of existing technologies. Furthermore, the industrial-scale application of regeneration technologies and the precise regeneration of various types of graphite are expected to be key research directions. These advances will facilitate the closed-loop utilization of LIBs materials, ensure strategic resource supply, and contribute to the development of sustainable energy.