2026 Romero Guillen Critical metals leaching from LIBs with aluminum

This study investigates the hydrometallurgical extraction of critical metals from various types of lithium-ion batteries, particularly focusing on the effectiveness of aluminum as a reducing agent. Using physical processing materials including aluminum- and graphite-active material combinations, leaching tests were performed on cylindrical NMC532, NCA, and prismatic NMC-LMO cells with sulfuric acid at differing concentrations and solid-to-liquid ratios. The experiments were aimed at optimizing conditions to maximize metal recovery efficiencies, achieving over 99% for lithium, nickel, manganese, and cobalt under ideal conditions. Factors such as increasing acid concentration and manipulating solid-to-liquid ratios were key determinants of extraction effectiveness. Experimental results demonstrated that a two-stage leaching process utilizing equal mixtures of aluminum and active material as well as graphite resulted in high efficiencies, specifically 94% for manganese, 93% for nickel, 92% for cobalt, and 94% for lithium. Additionally, tests on black mass supported reliable metal recovery, illustrating the potential of aluminum to enhance leaching rates while mitigating copper leaching issues, thus contributing to a more sustainable recycling process. This work underscores the viability of utilizing aluminum as a sustainable reducing agent in the recovery of metals from end-of-life lithium-ion batteries.