Synthesis of LiNi0.6Co0.2Mn0.2O2 from mixed cathode materials of spent lithium-ion batteries

Abstract

With the aggravation of resource shortage and environmental problems, the disposal of spent lithium-ion batteries becomes crucial. In this work, a sustainable closed-loop route to recycle mixed cathode materials from spent lithium-ion batteries is proposed. The sulfuric acid and H2O2 were used to leach mixed cathode powders, and parameters such as temperature, acid concentration, and time were investigated. The leaching efficiency of each metal was observed to be above 99%. The ternary cathode precursor was directly prepared from leachate. Li2CO3 was recovered from the residual solution by adding saturated Na2CO3. The mixture of precursor and Li2CO3 was roasted to resynthesize ternary cathode materials (LiNi0.6Co0.2Mn0.2O2). The characterization of LiNi0.6Co0.2Mn0.2O2, as well as its electrochemical performance was investigated. LiNi0.6Co0.2Mn0.2O2 possesses a layered structure and shows excellent cycling stability and rate capacity. The capacities at the first charge and discharge at 0.2C are 196.26 mA h·g−1 and 180.072 mA h·g−1, respectively. The coulombic efficiency after the second cycle is observed to be about 99%.