Recovery of valuable metals from spent ternary Li-ion batteries: Dissolution with amidosulfonic acid and d-glucose

For recovery of Li, Co, Ni and Mn from the spent lithium-ion batteries, a novel leaching process involving amidosulfonic acid as leaching agent and d-glucose as reducing agent was developed. The effects of parameters including temperature, amidosulfonic acid concentration, solid-to-liquid ratio (S/L ratio), mass ratio of d-glucose to cathode materials (d-glucose dosage) and leaching time on the leaching efficiencies of Co, Li, Mn and Ni were investigated. The leaching efficiencies reached 96.7% for Co, 98.4% for Li, 97.6% for Mn, and 98.3% for Ni under the most suitable conditions (90 °C, amidosulfonic acid of 1.5 mol L−1, S/L ratio of 50 g L−1, d-glucose dosage of 0.75, and 90 min). During the leaching process, with the dissolution of metals, the spherical particles of cathode materials firstly decomposed into small primary granules. Then valuable metals were further dissolved into leachate from these primary granules under the synergistic effect of H+ and d-glucose. Co-precipitation with oxalic acid recovered 99.9% of Co, 99.7% of Ni and 96.3% of Mn. The collected Co-Ni-Mn oxalate precipitates show homogeneous morphology and can be converted into well-shaped Co-Ni-Mn oxide by thermal treatment. Thus, the proposed process is found to be simple and efficient.