Design of Recycling Processes for NCA-Type Li-Ion Batteries from Electric Vehicles toward the Circular Economy

de Castro, R. H., Romano Espinosa, D. C., Gobo, L. A., Kumoto, E. A., Botelho Junior, A. B., & Tenorio, J. A. S. (2024). Design of Recycling Processes for NCA-Type Li-Ion Batteries from Electric Vehicles toward the Circular Economy. Energy & Fuels, 38(6), 5545–5557. https://doi.org/10.1021/acs.energyfuels.3c04904

Abstract

NCA batteries represent 8% of the market share, and the literature lacks recycling studies and routes toward a cost-effective recycling process. The present study aimed to develop the hydrometallurgical recycling process of NCA cylindrical batteries. The cells were discharged, followed by physical treatment before leaching. Three different acids were evaluated: H2SO4, H3PO4, and citric acid. Reducing agents were not necessary due to the presence of Al foils, which reduces leaching costs. Citric acid represented a better cost-effective option, but solid–liquid separation represents a drawback to the process. After H2SO4 leaching at 90 °C for 90 min in a solid–liquid ratio of 1/5 and 2.0 mol/L without Cu leaching, Al was separated by precipitation followed by solvent extraction for Co separation using Cyanex 272. Ni was obtained as hydroxide, and Li crystallized as sulfate. The mass balance demonstrated that about 92% of Li, 80% of Ni, and 85% of Co can be recovered in hydrometallurgical processing. Products with purity >95% can be used in battery and stainless-steel production. The process has the potential to have a low CO2 footprint, and future studies will explore it.