Insights on the process of battery grade nickel production via ion-exchange technology

Abstract In recent years, recycling of Li-ion batteries to recover valuable metals has become critically important to comply with new European Union regulations, which mandate the recovery of high-purity strategic metals (95% in Co, Ni, Cu, and 80% in lithium by the end of 2031). This work proposes a hydrometallurgical route combining oxidative precipitation with ion-exchange purification block for cobalt-free cathode active materials, specifically LMNO. Oxidative precipitation allows manganese recovery without the addition of any organic reagents; however, the process suffers from limited selectivity, resulting in nickel co-precipitation. This study highlights the integration of an ion-exchange purification block using Dowex™ M4195 to recover Ni from precipitated Mn solids and residual Ni-Li solution post oxidative precipitation. Despite the presence of high sodium and potassium impurities (> 20 g∙L − 1 ) in residual Ni-Li solution, the selectivity of these resins for Ni allows the production of high purity nickel solution and therefore high purity battery grade Ni precursors > 99.9%.