Study on the Preparation of the Cathode Materials for Lithium-Ion Batteries by Multiphase Redox Method

We report a new method, which is called multiphase redox method, to prepare LiMn2O4 cathode material. The precursors of LiMn2O4 were synthetized in Mn(OH)2-H2O-LiOH solution system by using air, oxygen or KMnO4 as the oxidant. The oxidation ability of the oxidant has an important influence on the amount of lithium embedding. Meanwhile, the sintering process and the electrochemical performance of the sintered samples are studied as well. The sample sintered at 820℃ for 10 h presents both high discharge capacity and excellent cycle performance. Compared with LiMn2O4 prepared by solid-state method, the uniformity in chemical composition of LiMn2O4 prepared by multiphase redox method is bettered significantly and the differences in micro-components of LiMn2O4 are almost eliminated, thus improving the electrochemical performance of LiMn2O4 prepared by multiphase redox method.