Zhang Ruihan, Shi Xingyi, Esan Oladapo Christopher, An Liang
Department of Mechanical Engineering The Hong Kong Polytechnic University Hung Hom Kowloon Hong Kong SAR 999077 China.
Glob Chall. 2022 Jun 11;6(12):2200050. doi: 10.1002/gch2.202200050. eCollection 2022 Dec.
Lithium-ion batteries (LIBs) are regarded to be the most promising electrochemical energy storage device for portable electronics as well as electrical vehicles. However, due to their limited-service life, tons of spent LIBs are expected to be produced in the recent years. Suitable recycling technology is therefore becoming more and more important as improper treatment of spent LIBs, especially the aged organic electrolyte, can cause severe environmental pollution and threats to human health. The organic solvents and high concentration of lithium salts in aged electrolytes are always sensitive toward water and air, which would easily hydrolyze and decompose into toxic fluorine-containing compounds, leading to severe fluorine pollution of the surrounding environment. Hence, recycling aged electrolytes from spent LIBs is an efficient way to avoid this potential risk to the environment. However, several issues inhibit the realization of electrolyte recycling, including the volatile, inflammable, and toxic nature of the electrolytes, the difficulty to extract electrolytes from the electrodes and separators, and various electrolyte compositions inside LIBs from different applications and companies. Herein, the current progress in recycling methods for aged electrolytes from spent LIBs is summarized and perspectives on future development of electrolyte recycling are presented.
锂离子电池（LIBs）被认为是用于便携式电子设备以及电动汽车的最有前景的电化学储能装置。然而，由于其使用寿命有限，预计近年来将产生大量废旧锂离子电池。因此，合适的回收技术变得越来越重要，因为对废旧锂离子电池，尤其是老化的有机电解质处理不当会造成严重的环境污染并威胁人类健康。老化电解质中的有机溶剂和高浓度锂盐对水和空气总是很敏感，它们很容易水解并分解成有毒的含氟化合物，导致周围环境受到严重的氟污染。因此，从废旧锂离子电池中回收老化电解质是避免这种潜在环境风险的有效方法。然而，有几个问题阻碍了电解质回收的实现，包括电解质的挥发性、易燃性和毒性，从电极和隔膜中提取电解质的困难，以及来自不同应用和公司的锂离子电池内部各种电解质成分。在此，总结了从废旧锂离子电池中回收老化电解质的方法的当前进展，并对电解质回收的未来发展提出了展望。
