Deep eutectic solvents (DESs) have been proposed as green alternatives for recycling lithium-ion battery (LIB) cathode materials. In the present work, a sustainable DES based on choline chloride and L-(+)-tartaric acid has been systematically investigated for leaching of a LIB cathode material (LiCo_1/3Ni_1/3Mn_1/3O₂) for the first time. Moreover, in a novel approach, antisolvent crystallization has been applied to recover metals from the DES leachate. The L-(+)-tartaric acid-based DES shows a good leaching capacity and a high leaching rate at 70 °C. Furthermore, antisolvent crystallization is shown to enable a high metal recovery efficiency of cobalt, nickel and manganese (>98.5%). The precipitate from antisolvent crystallization can be used as a precursor for the synthesis of new cathode material, while the remaining DES and antisolvent can be recovered for reuse in the process. This work presents a green, effective and closed-loop metal recovery strategy for recycling LIB cathode materials using a sustainable DES.

已提出深共晶溶剂 (DES) 作为回收锂离子电池 (LIB) 正极材料的绿色替代品。在目前的工作中，基于氯化胆碱和 L-(+)-酒石酸的可持续 DES 已被系统地研究用于浸出 LIB 正极材料 (LiCo _1/3 Ni _1/3 Mn _1/3 O ₂) 第一次。此外，在一种新的方法中，反溶剂结晶已被用于从 DES 渗滤液中回收金属。基于 L-(+)-酒石酸的 DES 在 70 °C 下表现出良好的浸出能力和高浸出率。此外，反溶剂结晶显示能够实现钴、镍和锰的高金属回收效率（>98.5%）。反溶剂结晶产生的沉淀物可用作合成新正极材料的前体，而剩余的 DES 和反溶剂可回收再利用。这项工作提出了一种绿色、有效和闭环的金属回收策略，用于使用可持续的 DES 回收 LIB 正极材料。