Department of Materials Engineering, Tarbiat Modares University, P.O. Box 4838-141 Tehran, I.R. IRAN
LiMn2O4 spinel cathode materials have been successfully synthesized by solid-state reaction. Surface of these particles were modified by nanostructured LiFePO4 via sol gel dip coating method. Synthesized products were characterized by thermally analyzed by Thermogravimetric and Differential Thermal Analysis(TG/DTA), X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Energy Dispersive X-ray (EDX) spectroscopy. The results of electrochemical tests showed that the charge/discharge capacities improved up to 120 mAh/g and charge retention of battery enhanced over %95. This improved electrochemical performance is caused by LiFePO4 phosphate layer on surfaces of LiMn2O4cathode particles.
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