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 LiCo _0.99Ti_0.01O₂ material. XPS observation further tells that in LiCo_0.998Ti_0.002O₂ 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 LiCo_0.998Ti _0.002O₂ is as good as that of LiCoO₂/LiCo _0.99Ti_0.01O₂ 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 LiCoO ₂ materials is more likely to originate from the different particle characteristics, when their Ti amounts are low enough.