The Recovery of All-Metals and Fluorine Resources from Used Lithium-Ion Batteries

Lithium-ion battery (LIB) recycling is of critical importance, but previous efforts mainly focused on recovering transition metals (TMs), while overlooking the regaining of Li-resources and the control of fluorine pollution. Here, we propose a strategy for recovering both lithium and TMs from the electrolyte and cathode of used LIBs while simultaneously addressing fluorine pollution. The recovery process involves extracting lithium and 1/6 of F from LiPF₆ in the electrolyte, forming LiF at a yield of 93.0%. The remaining 5/6 F in LiPF₆ is captured by NaOH and transforms into NaF in a yield of 93.9%. Different recovery routes of Li and TMs in the cathode were compared, including formic-acid leaching, and following direct recalcination, formic-acid leaching and then separating TM and Li using different precipitants. Furthermore, the recovered salts can be used in the repreparation of LiNi_xCo_yMn_zO₂ (x + y + z = 1). This work presents a cost-efficient strategy for the comprehensive recovery of all-metals from used LIBs and fixation of fluorine simultaneously.