Thermochemically driven layer structure collapse via sulfate roasting toward the selective extraction of lithium and cobalt from spent LiCoO2 batteries

• Published in: Journal of power sources Vol. 572; p. 233094
• Main Authors: He, Minyu, Rohani, Sohrab, Teng, Liumei, Gao, Yuxiang, Jin, Xi, Zhang, Xiufeng, Liu, Qingcai, Liu, Weizao
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.07.2023
• Subjects: Copperas; Recycling; Redox reaction; Spent lithium-ion batteries; Sulfation roasting; Copperas; Spent lithium-ion batteries; Recycling; Sulfation roasting; Redox reaction
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2023.233094

With the rapid development of new energy devices, a large amount of spent lithium-ion batteries (LIBs) are produced every year. Recovering valuable metals from spent LIBs is significant for achieving environmental protection and alleviating resource shortages. In this study, a novel approach by in situ thermal reduction technology with waste copperas is developed to recycle valuable metals from spent LiCoO2 (LCO) batteries. The mechanism study through in situ x-ray diffractometer and thermal analysis reveal that the sulfation of LCO underwent two pathways i.e., ion exchange and gas-solid reactions. In the ion exchange pathway, the layered structure of LCO collapse due to the reduction by divalent iron in copperas, and the detachment of lithium ions result in a larger lattice spacing of transition metal layer and formation of a stable spinel structure. Furthermore, the SO2 generated from the decomposition of iron sulfates reduces the unreacted LCO through gas-solid interactions, realizing the sulfation of lithium and cobalt completely. Economic analysis indicates the potential benefit of this process is approximately 8266$/t spent LCO. This study provides an alternative technological route and a new approach to green recovery of the spent LCO batteries, exhibiting great potential for wide applications. [Display omitted] •This study employed the concept of “waste to wealth”.•The conversion efficiency of Li and Co reached 100% after sulfation reaction.•An environmentally friendly approach for recycling spent LiCoO2 battery is proposed.•The mechanism of the sulfation reaction of LiCoO2 was obtained.