Hydrometallurgical recovery of lithium carbonate and iron phosphate from blended cathode materials of spent lithium‐ion battery

Abstract

Abstract The recycling of cathode materials from spent lithium‐ion battery has attracted extensive attention, but few research have focused on spent blended cathode materials. In reality, the blended materials of lithium iron phosphate and ternary are widely used in electric vehicles, so it is critical to design an effective recycling technique. In this study, an efficient method for recovering Li and Fe from the blended cathode materials of spent LiFePO 4 and LiNi x Co y Mn 1‐ x‐y O 2 batteries is proposed. First, 87% Al was removed by alkali leaching. Then, 91.65% Li, 72.08% Ni, 64.6% Co and 71.66% Mn were further separated by selective leaching with H 2 SO 4 and H 2 O 2 . Li, Ni, Co and Mn in solution were recovered in the form of Li 2 CO 3 and hydroxide respectively. Subsequently, 98.38% Fe was leached from the residue by two stage process, and it is recovered as FePO 4 ·2H 2 O with a purity of 99.5% by precipitation. Fe and P were present in FePO 4 ·2H 2 O in amounts of 28.34% and 15.98%, respectively. Additionally, the drift and control of various components were discussed, and cost–benefit analysis was used to assess the feasibility of potential application.