Direct Regeneration of Cathodes from Spent LIB Black Mass through Integrated Roasting-Flotation with Impurity-Tailored Self-Decontamination

Abstract

Addressing the critical incompatibility between direct recovery technology and industrial battery-crushing technology, this work proposes a short-process, eco-friendly strategy for the direct regeneration of cathode material from spent lithium- ion battery black mass (BM). In the strategy, the cathode material (designated S-NCM) with a 99.08% recovery and a 95.92% grade is firstly extracted greenly and nondestructively via flotation separation after roasting pretreatment. Crucially, residual metal impurities in the BM are ingeniously utilized to capture fluorinated pollutants (e.g., HF) during the roasting process, effectively eliminating hazardous gas emissions. Following targeted prelithiation and high temperature sintering, S-NCM is transformed into regenerated cathode material (R-NCM). Electrochemical tests demonstrate that R-NCM delivers a reversible specific capacity of 139.27 mAh·g−1 at 0.1 C and maintains 91.85% capacity retention after 100 cycles. Techno-economic analysis confirms the strategy’s significant environmental benefits and commercial viability. The total energy consumption of direct regenerating (2.88 MJ·kg−1) is substantially lower than that of pyro-methods (39.12 MJ·kg−1) and hydro-methods (42.97 MJ·kg−1). Owing to its process simplicity, low energy demand, and elimination of secondary synthesis, the regenerated cathode material can directly serve battery remanufacturing. Consequently, the direct regenerating strategy offers 6.8-fold and 2.4-fold higher profitability compared to pyro- and hydro- methods, respectively. This work provides a sustainable solution for large-scale direct regeneration of spent battery-derived BM.