Resynthesis of LiCo1−xMnxO2 as a cathode material for lithium secondary batteries

Abstract

A recycling process involving chemical, mechanical, and electrochemical steps has been applied to recover cobalt from spent lithium ion batteries and resynthesize cathode active materials. LiCo1−xMnxO2 powders using Co salt including Mn from the leach liquor were resynthesized by solid-state reaction as cathode active materials. When the powder mixture with added Li salt was calcined at 950 °C for 8 hours, well crystallined LiCo1−xMnxO2 was successfully obtained. The LiCo1−xMnxO2 powders with a ratio of Co:Mn=10:1 has a discharge capacity of 156.3 mAh/g at a rate of 20 mA/g with no perceptible capacity loss, in sharp contrast to the pure LiCoO2 as active materials. The resynthesized LiCo1−xMnxO2 was proven to have good characteristics as cathode active materials in charge/discharge capacity and cyclic performance.