High‐selective separation recovery of Ni, Co, and Mn from the spent LIBs via acid dissolution and multistage oxidation precipitation

Abstract For recovering Ni, Co, and Mn from lithium‐ion batteries, traditional chemical precipitation methods demonstrate low selectivity and significantly contribute to environmental pollution. This study proposes a separation recovery technique for transition metals, specifically Ni, Co, and Mn, from spent LIBs, involving “acid dissolution” and “multistage oxidation precipitation”. More than 98 % of transition metals can be extracted from spent LIBs using a low acid concentration (0.5 M) without reducing agents. The feasibility of separating different metals via multistage oxidation precipitation, based on their different electrode potentials for oxidizing Me 2+ (Me=Mn/Co/Ni), was confirmed. The combination of oxidizing agent S 2 O 8 2− and the precipitant OH − was universally applied to the fractional precipitation of Mn, Co, and Ni respectively. About 99 % of Mn, 97.06 % Co, and 96.62 % Ni could be precipitated sequentially by changing the concentrations of S 2 O 8 2− and the pH value of solution. XRD, XPS, XRF, ICP‐MS and other methods were employed to elucidate the mechanism behind the multistage oxidation precipitation of target metal compounds, exploiting the differential electrode potentials for oxidizing Me 2+ ions. This technique surpasses traditional solvent extraction in cost‐effectiveness and selectivity, showing promise for large‐scale industrial applications in recovering Mn, Co, and Ni.