The elevated temperature performance of LiMn2O4 coated with Li4Ti5O12 for lithium ion battery

Cathode material LiMn2O4 was synthesized by sol-gel method and coated with Li4Ti5O12 in order to enhance the electrochemical performance at room and elevated temperature. The unmodified and surface-modified LiMn2O4 were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The XRD and SEM results indicated that Li4Ti5O12, particles had been encapsulated on the surface of the LiMn2O4 without any crystal structure change of LiMn2O4. The 2 mol% and 5 mol% Li4Ti5O12-coated LiMn2O4 showed an excellent capacity retention at room temperature and 55 degrees C compared to pure LiMn2O4. The improvement of electrochemical performance is attributed to the suppression of electrolyte decomposition on the surface of LiMn2O4. The results revealed that surface-modification of LiMn2O4 with Li4Ti5O12 should be an effective way to improve the cycling properties at room and elevated temperatures. (c) 2007 Elsevier B.V. All rights reserved.