Abstract Scope |
Critical metals recovery from waste lithium-ion batteries (LIBs) is vital for advancing energy technologies. This study investigates the leaching performance of two deep eutectic solvents (DESs), namely choline chloride (ChCl):L-ascorbic acid (LAA):H2O (2:1:6) and ChCl:urea (1:2), for the selective extraction of Li, Co, Ni, and Mn from NMC811 cathode materials. To the best of our knowledge, these DESs have not been previously utilized for leaching NMC811, although they have shown promise in related systems. A design of experiments methodology was employed to systematically investigate the effects of temperature, solid-to-liquid ratio, and duration. The ChCl:LAA:H2O system achieved leaching efficiencies of 83.8% for Li, 100% for Co, 100% for Ni, and 94.5% for Mn, while the ChCl:urea system yielded 83.1% Li, 100% Co, 100% Ni, and 87.5% Mn recovery. Thorough material characterization was performed before and after leaching to develop a furthered understanding of reaction mechanisms, phase transformations, and surface chemistry evolution. |