HIGH POWER PERFORMANCE OF MULTICOMPONENT OLIVINE CATHODE MATERIAL FOR LITHIUM-ION BATTERIES

A multicomponent olivine cathode material, LiMn_0.4Fe_0.6PO₄ , was synthesized via a novel coprecipitation method of the mixed transition metal oxalate. X-ray diffraction patterns indicate that carbon-coated LiMn_0.4Fe_0.6PO₄ has been prepared successfully and that LiMn_0.4Fe_0.6PO₄/C is crystallized in an orthorhombic structure without noticeable impurity. Homogeneous distribution of Mn and Fe in LiMn_0.4Fe_0.6PO₄/C can be observed from the scanning electron microscopy (SEM) and the corresponding energy dispersive X-ray spectrometry (EDS) analysis. Hence, the electrochemical activity of each transition metal in the olivine synthesized via coprecipitation method was enhanced remarkably, as indicated by the galvanostatic charge/discharge measurement. The synthesized LiMn_0.4Fe_0.6PO₄/C exhibits a high capacity of 158.6 ± 3 mAhg^-1 at 0.1 C, delivering an excellent rate capability of 122.6 ± 3 mAhg^-1 at 10 C and 114.9 ± 3 mAhg^-1 at 20 C.