Green and Low-Cost Approach for Recovering Valuable Metals from Spent Lithium-Ion Batteries

Spent lithium-ion batteries (LIBs) are increasingly produced as the consumption of LIBs for electric vehicles and 3C products is increasing. Herein, a process to recycle valuable metals from the cathodes of LIBs is proposed, in which the separation of aluminum foil and cathode material is realized by calcining the spent cathode sheet in CO2. The spent aluminum foil separated from cathode sheet is used as a reducing agent to displace Ni2+, Co2+, and Mn2+ in the leachate to generate high-purity Ni–Co–Mn nanopowders. In addition, the recovery efficiencies of Li, Ni, Co, and Mn are 95.04, 97.5, 99.3, and 4%, respectively. Ternary cathode materials are synthesized by the solid-phase method using the reduction products as the precursors. The initial discharge capacity of the synthetic material at 0.2 C reaches 165 mA h g–1. The use of the spent aluminum current collector reduces the consumption of auxiliary materials, and the aluminum current collector is transformed from waste into a high-value-added reductant, greatly lowering the process costs and also making the process green. Finally, an economic and energy consumption analysis of the entire process is performed. This green and low-cost process achieves a closed loop of LIBs, which is critical to support sustainable expansion of the LIB production.