One‐Pot Direct Recycling of Spent LiCoO 2 via Synergistic Binder Defluorination and Phase Reconstruction

Abstract

ABSTRACT Direct recycling of spent lithium‐ion battery cathodes is hindered by two interdependent challenges: persistent polyvinylidene fluoride (PVDF) binder residues that block particle surfaces and incomplete structural repair of degraded layered phases. Here, we report a one‐pot regeneration strategy based on a Li + ‐containing deep eutectic solvent (Li + ‐DES) that integrates targeted defluorination and phase reconstruction within a reusable medium. Under mild conditions, the functionalized Li + ‐DES selectively cleaves C─F bonds of PVDF, enabling complete binder removal and interface purification. Without any solvent exchange, the same Li + ‐DES serves as a lithium‐rich repair medium, in which enhanced Li + coordination and transport promote the formation of a uniform pre‐lithiation layer and facilitate the conversion of inactive spinel Co 3 O 4 back into well‐ordered layered LiCoO 2 upon annealing. The regenerated LiCoO 2 delivers a discharge capacity of 157.4 mAh g −1 at 0.1 C, retains 83.1% of its capacity after 300 cycles, and maintains stable cycling even at 4.6 V. By integrating defluorination, Li replenishment, and structural reconstruction into a single reusable system, this work provides a simplified, energy‐efficient, and sustainable route for closed‐loop recycling of degraded cathode materials.