Abstract
The rapid growth of lithium-ion battery (LIB) production and the emerging recycling industry have intensified the need for efficient hydrometallurgical processes capable of recovering battery-grade metals/materials from the End of Life (EoL) batteries and scraps. A critical challenge in these flowsheets is the effective removal of impurities-including Al, Fe, F, Cu, Mn, Mg, and Ca-introduced through spent electrode materials, current collectors, and mechanical preprocessing steps. These impurities can negatively impact downstream solvent extraction, crystallization, and product purity requirements for battery-grade‑ nickel, cobalt, and lithium products.
This study evaluates impurity removal strategies within a typical black mass leaching circuit, emphasizing pH-dependent separation, selective precipitation, oxidation and solvent extraction mechanisms. The findings highlight that an integrated impurity management strategy can reduce reagent consumption, minimize co‑precipitation losses of critical metals, and improve the overall efficiency and economic viability of hydrometallurgical LIBs recycling. This work provides practical insights for designing robust impurity removal circuits as the recycling sector scales to meet growing global demand for critical minerals.