Advanced absolute chemical precipitation for high-purity metal recovery in all-types of lithium-ion battery recycling

Conventional chemical precipitation methods face challenges in selectively recovering valuable metals from mixed spent lithium-ion batteries (LIBs) due to the similar chemical properties of Mn, Co, and Ni. This study introduces a novel absolute chemical precipitation process for the stepwise recovery of metals, beginning with leaching followed by selective precipitation. The process achieves leaching efficiencies exceeding 90 % for Co, Ni, Mn, and Li under optimal conditions (1 h, 70 degrees C, 3.5 mol/L H2SO4, 8 vol% H2O2, and 20 g/L pulp density). Subsequent precipitation steps deliver high-purity recoveries of FePO4 (97.22 %), MnO2 (94.1 %), Co2O3 & sdot;3H2O (98.7 %), Ni(OH)2 (95.9 %), and Li2CO3 (99.8 %), with precipitation percentages exceeding 98 %. The method is effective across diverse LIB chemistries, including LiNi x Co y Mn (1-x-y) O 2 (NCM), LiFePO4 (LFP), LiM2O4 (LMO), LiNi x Co y Al (1-x-y) O 2 (NCA), and LiCoO2 (LCO), without requiring pre-sorting. Pilot-scale validation using a 5 kg batch of mixed spent LIB cathode and anode active materials confirmed the process's scalability and consistent high recovery efficiencies, achieving purities exceeding 90 % for all recovered metals. By utilizing low-cost, nontoxic reagents and moderate processing temperatures, this method minimizes hazardous waste generation and operational costs, offering a sustainable and scalable solution for critical metal recovery of spent LIBs.