Electrochemical characterizations of surface modified LiMn2O4 cathode materials for high temperature lithium battery applications

Abstract LiMn 2 O 4 spinel cathode materials were coated with 2.0 wt.% of La 2 O 3 by polymeric process followed by calcinations at 400 °C and 800 °C for 6 h in air. The surface coated LiMn 2 O 4 cathode materials were physically characterized using X-ray diffraction, Scanning electron microscopy, Transmission electron microscopy and X-ray photoelectron spectroscopy. La 2 O 3 -coated LiMn 2 O 4 coating did not affect the crystal structure and space group Fd3m of the cathode materials compared to the uncoated LiMn 2 O 4 . The surface morphology and particle agglomeration were investigated and compact coating layer on the surface of the core materials. La 2 O 3 was completely coated over the surface of the LiMn 2 O 4 core cathode materials. The galvanostatic charge and discharge of the La 2 O 3 -coated LiMn 2 O 4 cathode materials were carried out at 0.1 mA/g in the range of 3.0 and 4.5 V at 30 °C and 60 °C. Based on the results, La 2 O 3- coated spinel LiMn 2 O 4 cathode at 800 °C has improved the structural stability, high reversible capacity and excellent electrochemical performances of the rechargeable lithium batteries.