Synthesis and Electrochemical Properties of Li_(0.97+δ)Ti_(0.03)Fe_(0.97)Mn_(0.03)PO_4/C Composite Cathode Material

The composite cathode material of Li_(0.97+δ)Ti_(0.03)Fe_(0.97)Mn_(0.03)PO_4/C was synthesized by carbothermal reduction of Fe_(0.97)Mn_(0.03)PO_4 which was prepared by co-precipitation method.The sam- ples were characterized by X-ray diffraction,scanning electron microscope,FTIR absorption spectra, and their electrochemical performances were investigated in terms of rate discharge and cycling behavior. The results show that Li_(0.97+δ)Ti_(0.03)Fe_(0.97)Mn_(0.03)PO_4/C samples are simple pure olive-type phase,and the particles are homogeneous with average particle size of about 1μm.The ion dopants of Mn~(4+)and Ti~(4+)do not affect the structure of the material.Compared with LiFePO_4/C,the composite compound Li_(0.97+δ)Ti_(0.03)Fe_(0.97)Mn_(0.03)PO_4/C exhibits good electrode properties with discharge capacities of 134.0, 133.4,130.1 and 127.2mAh.g~(-1)at 0.2,1,5 and 10C rates,respectively.In addition,it shows excellent cycle stability at different rates.