ABSTRACT Direct recycling offers a promising alternative for regenerating spent Li‐ion batteries (LIBs); however, achieving high‐purity cathode and ensuring cost‐effectiveness remains challenging. Herein, we present an innovative integrated process that simultaneously enables delamination and relithiation of spent cathodes, Li x Ni 0.6 Co 0.2 Mn 0.2 O 2 and Li x FePO 4 , under open‐air conditions with minimal energy. By oxidizing diethylene glycol, a green solvent, the transition‐metal oxidation state in the cathode is effectively reduced, thereby facilitating Li reinsertion into the structure. Consequently, the formation of glycol aldehyde induces 100% electrode delamination, enabling a one‐pot restoration pathway. The reaction mechanism is elucidated using Proton nuclear magnetic resonance ( 1 H‐NMR), Soft X‐ray absorption spectroscopy (soft‐XAS), and X‐ray absorption near‐edge structure spectroscopy (XANES), and the regenerated cathodes consistently recover over 99% of their electrochemical performance for both 2 and 50 Ah cells. Furthermore, the regeneration solution is reusable, requiring only Li salt supplementation. This study presents a practical, low‐cost, and environmentally friendly approach for advancing the scalability and feasibility of direct LIB recycling technologies.
Song et al. (Mon,) studied this question.