As the global consumption of lithium-ion batteries increased dramatically, recycling spent lithium-ion batteries became an urgent task, which is vital to alleviate resource shortages and maintain sustainable development. In this study, a strategy for preferential extraction of lithium from spent LiCoO2 (LCO) cathodes by chlorination roasting combined with water leaching was proposed, along with the regeneration of LCO cathodes with materials recycled from spent LCO. Calcium chloride (CaCl2) was selected for chlorination, and roasting temperature, dosage of CaCl2, and roasting time were optimized systematically. In this process, lithium was converted into water-soluble LiCl under a low chlorination atmosphere, the relatively stable Co-O octahedral structure was maintained in the solid phase, and preferential extraction of lithium was completed by subsequent water-leaching. The experimental results showed that 99.49% of Li was selectively recovered as LiCl which was further recovered as battery-grade Li2CO3, and 98.12% of Co was recovered in the form of Co3O4. Regenerated LCO cathodes (r-LCO) from recovered Li2CO3 and Co3O4, exhibited excellent electrochemical performance with a capacity of 141.2 mAh g−1 at 1 C and a high-capacity retention of 91.8% after 100 cycles.

中文翻译：

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从废 LiCoO2 阴极优先提取锂和 LiCoO2 阴极再生


随着全球锂离子电池消费量的急剧增加，回收废旧锂离子电池成为一项紧迫的任务，这对于缓解资源短缺和保持可持续发展至关重要。在这项研究中，提出了一种通过氯化焙烧结合水浸出从废 LiCoO2 （LCO） 阴极中优先提取锂的策略，以及用从废 LCO 中回收的材料再生 LCO 阴极。选择氯化钙 （CaCl2） 进行氯化，系统优化焙烧温度、CaCl2 用量和焙烧时间。在该工艺中，锂在低氯化气氛下转化为水溶性 LiCl，在固相中保持相对稳定的 Co-O 八面体结构，并通过随后的水浸出完成锂的优先提取。实验结果表明，99.49% 的 Li 被选择性回收为 LiCl，进一步回收为电池级 Li2CO3,98.12% 的 Co 以 Co3O4 的形式回收。从回收的 Li2CO3 和 Co3O4 中再生的 LCO 阴极 （r-LCO） 表现出优异的电化学性能，在 1 C 时容量为 141.2 mAh g-1，循环 100 次后容量保持率高达 91.8%。