Direct Recovery and Efficient Reutilization of Degraded Ternary Cathode Materials from Spent Lithium-Ion Batteries via a Homogeneous Thermochemical Process

Efficient recycling of cathode materials in scrapped lithium-ion batteries is urgent for the sustainable supply of the transition-metal and lithium resources. The conventional processes always extract the elements as raw materials for the resynthesis of cathode materials, leading to tedious disposal of corrosive liquid wastes. From the perspective of industrial processing, the collected waste batteries usually contain impurities (such as carbon-based conductive agents). Herein, we report a facile strategy to directly recover degraded ternary cathode materials in the presence of acetylene black using deliberately selected molten salt medium. Taking degraded LiNi0.5Co0.2Mn0.3O2 (NCM523), for example, after regeneration, the degraded NCM523 particles can directly recover the pristine α-NaFeO2-type structure and specific capacity compared to commercial materials. The intrinsic network structures between NCM523 and carbon in the spent cathodes can trigger a faster relithiation process. This work not only provides a simple and environment-friendly method for recovering degraded ternary cathode materials but also gives a new clue to efficiently recycle and reuse waste energy storage materials.