Fe Content Effects on Electrochemical Properties of 0.3Li_2MnO_3-0.7LiMn_xNi_xFe_(1-2x)/_2O_2 Cathode Materials

摘要

The cathode materials 0.3Li_2MnO_3-0.7LiMn_xNiNi_xFe_(1-2x)/_2O_2(0.35<=x<=0.5) were synthesized via low-heating solid-state reaction method. The prepared samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TG) and differential thermal analysis (DTA), and their electrochemical performances were also investigated here. The FESEM images of samples revealed that the particle of Fe-substituted samples became smaller and size distribution got narrower compared with the materials without Fe-doping. The results showed that electrochemical properties of the material depended on the content of Fe. 0.3Li_2MnO_3 -0.7LiMn_(0.4)Ni_(0.4)Fe_2O_2 maintained 99.5% of the reversible capacity after 60 cycles.