The investigation of Ti-modified LiCoO2 materials for lithium ion battery

EDAX measurement reveals that the atomic ratio of Ti/(Ti + Co) is much higher than the mole feed ratios in the preparation for the LiCo0.99Ti0.01O2 material. XPS observation further tells that in LiCo0.998Ti0.002O2 phase with quite low Ti amount, almost no Ti can enter into the LiCoO2 lattice, it is more inclined to enrich in the particle surface. Electrochemical examinations show that the cycling stability of LiCo0.998Ti0.002O2 is as good as that of LiCoO2/LiCo0.99Ti0.01O2 composite between 3.0 and 4.3 V, and the latter has a better rate performance. It is considered that the difference of the high rate performance between the Ti-modified LiCoO2 materials is more likely to originate from the different particle characteristics, when their Ti amounts are low enough.