Effects of manganese sources on the high temperature performance of spinel LiMn2O4

To research the effect of different manganese sources on the prepared spinel LiMn2O4 (LMO), the precursors of the manganese sources were prepared by the precipitation method. And then, the most commonly used manganese oxides (MnO2, Mn2O3, and Mn3O4) were prepared by different calcination temperatures. The LMO cathode materials were prepared with manganese oxides under the same preparation conditions. And the relationship between manganese sources and the electrochemical performance of the obtained cathode materials was investigated by examining the morphology and electrochemical properties of LMO. The research result showed that different manganese oxides with different morphological structures can be obtained from the same precursor at different calcination temperatures. The morphology structures of LMOs and the contents and sizes of octahedral crystals were different. LMO prepared from Mn2O3 had the most octahedral crystals and the most uniform size. It also had the best capacity performance, rate performance, and cycle performance among the three LMOs: the first discharge-specific capacity was 131.8 mAh.g(-1) (0.2C); the discharge-specific capacity of 100.4 mAh.g(-1) at 3C; after 100 cycles at 0.5C (half-cell), the discharge specific capacity was still 116.0 mAh.g(-1), and the capacity retention rate was 93.9%, which is far superior to the other two LMOs, indicating a good application prospect. Even at a high temperature of 55 degrees C, LMO from Mn2O3 exhibited significantly higher rate performance and stronger anti-attenuation ability than the other two LMOs.