A Combined Method of Leaching and Co-Precipitation for Recycling Spent Lini 0.6 Co 0.2 Mn 0.2 O 2 Cathode Materials: Process Optimization and Performance Aspects

A novel recycling process of spent LiNi0.6Co0.2Mn0.2O2 cathode materials has been developed. The process comprises acid leaching followed by regeneration of LiNi0.6Co0.2Mn0.2O2 materials with carbonate co-precipitation. Spent LiNi0.6Co0.2Mn0.2O2 materials were effectively leached in sulfuric acid and hydrogen peroxide solution. The leaching efficiencies were 97.8% for Li, 98.1% for Ni, 96.5% for Co, and 97.0% for Mn under the optimized conditions of H2O2 concentration of 3 vol.%, sulfuric acid concentration of 3.0 mol/L, solid–liquid ratio of 20 g/L, leaching temperature of 80°C, and reaction time of 60 min. Subsequently, LiNi0.6Co0.2Mn0.2O2 cathode materials were regenerated from the leaching solution. A regenerated LiNi0.6Co0.2Mn0.2O2 cathode produced a great initial discharge capacity of 173.4 mAh g−1 at 0.1 C under a calcination temperature of 850°C. The capacity retention reached 93.6% after 100 cycles at 1 C. The novel process here would be applied in actual industrial production.