Regeneration of high-performance Li1.2Mn0.54Ni0.13Co0.13O2 cathode material from mixed spent lithium-ion batteries through selective ammonia leaching

Abstract

The efficient recycling process of spent lithium-ion batteries (LIBs) to regenerate electrode materials can alleviate the metal resources scarcity and environmental pollution. Here, the Li-rich cathode Li1.2Mn0.54Ni0.13Co0.13O2 (LR) material was successfully re-synthesized via an environment-friendly and impurity-free recycling process combined ammonia leaching with sol-gel process. Compared with the general methods, ammonia leaching is delicately applied to selectively extract valuable metals from spent LiNixCoyMnzO2 materials exclusive of other impurities (Fe, Al). The process facilitates the subsequent recovery without additional purification process. Surprisingly, the leaching efficiency of Li, Ni, and Co elements is up to as high as 99.28%, 99.63%, and 99.76%, respectively. After adding extra metal compounds stoichiometrically, LR with uniform particle size and elements distribution was regenerated from the valuable metals in the lixivium via the sol-gel method. The LR synthesized at 800 °C exhibits a satisfying capacity of 246.5 mAh g−1 at 0.1 C and high-stable cycle performance with a capacity of 163.3 mAh g−1 after 80 cycles at 0.2 C between 2.0 and 4.8 V. The fundamental results provide inspiration for recovery of the complex spent LIBs, which can selectively separate the multiple metal impurities with high-efficient reutilization.