A process for preferential recovery of lithium and manganese from spent NCM by vacuum carbothermal reduction method

Abstract

In this study, a process was developed for the preferential recovery of lithium and manganese from spent ternary lithium batteries using the vacuum carbothermal reduction method. Firstly, the electrolyte and PVDF in the cathode and anode wafers of the spent ternary lithium batteries were removed. Subsequently, lithium in the cathode powder was preferentially recovered under vacuum conditions using the anodic powder as a reducing agent. The findings show that at 1623 K and 25 %for 2 h, the reduction process generates Li2O, (NiO)m-(MnO)n, Ni, and Co as the ultimate products. Reduction roasting enables the preferential extraction of 99.99 % Li and 99.82 % Mn, which condense on the condensation tray as Li2O and MnOx, while Ni and Co are present in the residue as oxides and monomers. In summary, the whole process of the vacuum carbothermal reduction method achieves efficient extraction of Li and Mn while avoiding the subsequent recovery of Ni, Co, and Mn. It also minimizes Li loss and Mn contamination during the recovery of Ni and Co. Additionally, by utilizing the cathode material from waste LIBs. This process realises the use of waste for waste management, resulting in significant cost savings in recycling and reducing environmental harm.