Recycling of Li-ion batteries: hydrometallurgical flowchart, multivariate analysis, and life cycle assessment

In this paper, we are proposing a flexible flowchart for recycling Ni-rich Li-ion batteries by hydrometallurgy. Physical separation processing is important to separate cathode and anode fractions from plastic, external structure and foils (mostly Cu). Al foil partly remained in the black mass works as reducing agent reducing costs and environmental impacts of H2O2 use. H2SO4 is still the best option considering economic and environmental benefits. Mn separation occurs by ozone precipitation demonstrating a better option than solvent extraction reaching 99% efficiency with 96% purity. Ni and Co separation by ion exchange chelating resins (bis-picolylamine) has higher selectivity over Al and Li, and our experimental data and optimization modeling demonstrates that minor differences in particle size of resin beads impacts on adsorption capacity (Dowex M4195 < Lewatit TP 220). About 1.46 × 106 kg-CO2eq would be generated to produce 1 ton of LiOH, lower than mining process with recovery of 95% battery materials. The process could be used for recycling NMCs, NCA, and LCO cathode-type batteries with minor changes in process steps.