The Recycling of Spent Lithium-Ion Batteries: a Review of Current Processes and Technologies

Abstract

The application of lithium-ion batteries (LIBs) in consumer electronics and electric vehicles has been growing rapidly in recent years. This increased demand has greatly stimulated lithium-ion battery production, which subsequently has led to greatly increased quantities of spent LIBs. Because of this, considerable efforts are underway to minimize environmental pollution and reuse battery components. This article will review the current status of the main recycling processes for spent LIBs, including laboratory- and industrial-scale recycling processes. In addition, a brief review of the design and reaction mechanisms of LIBs will be provided, and typical physical, chemical, and bioleaching recycling processes will be discussed. The significance of recycling will also be emphasized in terms of economic benefits and environmental protection. Furthermore, due to the unprecedented development of electric vehicles, large quantities of retired power batteries are predicated to appear in the near future. And because of this, secondary uses of these retired power batteries will be discussed from an economic, technical, and environmental perspective. Finally, potential problems and challenges of current recycling processes and prospects of key recycling technologies will be addressed.

Keywords

Spent lithium-ion batteries / Recycling / Leaching / Secondary use

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Funding

National Natural Science Foundation of China(U1564206)