Advances in lithium-ion battery recycling: Strategies, pathways, and technologies

Abstract

The use of lithium-ion batteries in portable electronic devices and electric vehicles has become well-established, and battery demand is rapidly increasing annually. While technological innovations in electrode materials and battery performance have been pursued, the environmental threats and resource wastage posed by the resulting surge in used batteries have been overlooked. Spent batteries are technically inoperable but contain excess metal inside the structure, making recycling essential for environmental protection and recovery of scarce resources. The battery recycling industry has gradually emerged under the influence of government implementation and ecological protection trends. However, the annual recycling volume is still insufficient compared to the output volume of used batteries. Therefore, more recycling plants and advanced technologies are imperative to improve recycling efficiency. This article summarizes pretreatment, pyrometallurgical, and hydrometallurgical processes and technologies in three major parts, analyzes their applicability and environmental friendliness using industrial examples, highlights their technical shortcomings and problems, and emphasizes the bright future of battery recycling.

Keywords

Spent lithium-ion batteries / Recycling process / Pyrometallurgy / Hydrometallurgy / Metal recovery

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

CRediT authorship contribution statement

Ziwei Tong: Writing - review & editing, Writing - original draft. Mingyue Wang: Writing - review & editing. Zhongchao Bai: Supervision. Huijun Li: Supervision. Nana Wang: Writing - review & editing, Supervision.

Acknowledgements

This article is dedicated to Professor Yitai Qian, the supervisor of Nana Wang and Zhongchao Bai.

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