Lithium cobalt oxide （LiCoO2） was synthesized by carbon combustion synthesis （CCS） using carbon as fuel. X-ray diffraction （XRD） and scanning electron microscope （SEM） measurements showed that carbon combustion led to the formation of layered structure of LiCoO2 and the particle size could be controlled by carbon content. For the LiCoO2 sample prepared at 800℃ for 2 h, at molar ratio of C/Co = 0.5, the particle-size distribution fell in the narrow range of 3-5 μm. Electrochemical tests indicated this LiCoO2 sample delivered an initial discharge capacity of 148 mAh/g with capacity retention rate higher than 97% after 10 cycles.
Yongle Gan Li Zhang Yanxuan Wen Fan Wang Haifeng Su
LiNi0.5Mn1.5O4 was synthesized by combustion synthesis （UCS） using urea as fuel. X-ray diffraction and scanning electron microscope measurements showed that the spinel structure LiNio.sMnl.504 with the space group Fd3m was formed during urea combustion. Both structure and particle size could be adjusted by the amount of urea and the heat treatment temperature used in the UCS. For the LiNi0.5Mn1.5O4 sample prepared with a urea/Li molar ratio of 0.57 and a heat treatment temperature of 900℃, the particle-size distribution fell in a narrow range of 1-2 Dm. Electrochemical tests indicated that this LiNi0.sMnl.504 sample delivered a discharge capacity of 133.6 mAh/g with a capacity retention rate of 99.6% after 20 cycles at 0.5 C.
