Directly Repairing LiNi0.8Co0.1Mn0.1O2 from Spent Lithium-Ion Batteries Through LiNO3-KCl Eutectic Molten Salt

LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811) cathode materials are universally applied in electromobiles and digital electronic products for their high energy density. With the growth in demand for lithium-ion batteries (LIBs) and their limited lifespan, a plenty of end-of-life LIBs will need to be disposed in the coming years. Compared with recovery methods of thermometallurgy and hydrometallurgy for spent LIBs, the directly repairing method bears the merits of economical, safety, and sustainable. In this study, the LiNO 3 -KCl eutectic molten salt system was served as source of lithium and dissolvent to remove impurities and repair the deteriorated structure of NCM811 cathode materials. The effects of molten salt molar ratio and temperature on the direct repair process were systematically investigated. The optimum condition is direct repair regeneration at 600 °C using LiNO 3 and KCl molten salt with 3:7 (molar ratio). The repaired NCM811cathode material has good crystallinity, and the specific capacity can reach 185 mAh·g −1 at 0.1 C rate and maintain 80.58% capacity retention ratio after 100 charge-discharge cycles. Directly repairing through LiNO 3 -KCl eutectic molten salt offers a promising strategy for recovery and reuse of spent ternary LIBs.