AbstractRecycling of spent ternary lithium‐ion batteries (LIBs) is crucial for both resource recovery and environmental sustainability. Deep eutectic solvents (DESs), as an eco‐friendly leaching agent, offer a promising alternative to mineral acids for the metal recovery. However, current DES‐based systems primarily focus on binary LiCoO2 batteries and suffer from complex leaching conditions, including high operation temperature, long reaction time. Herein, a dual‐function green solution is synthesized using choline chloride and tartaric acid, enabling direct precipitation of nickel (Ni) and separation of cobalt (Co), manganese (Mn), and lithium (Li) within 50 min at 100 °C, without requiring additional reducing agents throughout the process. The recovery efficiency of Li, Ni, Co, and Mn reached 99.2%, 97.3%, 94.4%, and 94.1%, respectively, while the purity of Ni products approached 99.9%. The used system is suitable for recycling various types of ternary batteries. Additionally, both theoretical and experimental analyses reveal that Ni ions exhibit superior binding energy and coordination with DESs compared to other ions, attributed to the synergistic effect of strong interaction and stable chelation. This research offers a promising method for the replenishment of essential metal resources.
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