Solid-state synthesis of LiCoO_2/LiCo_(0.99)Ti_(0.01)O_2 composite as cathode material for lithium ion batteries

摘要

We have fabricated a micron-sized LiCoO_2/LiCo_(0.99)Ti_(0.01)O_2 composite successfully by solid-phase synthesis, its core-shell structure has been proved by SEM and XPS observation. Electrochemical examinations show that comparing with LiCoO_2 and LiCo_(0.99)Ti_(0.01)O_2, the obtained LiCoO_2/LiCo_(0.99)Ti_(0.01)O_2 composite presents greatly enhanced cycling stability as well as rate capability. In addition, DSC measurement indicates that LiCoO_2/LiCo_(0.99)Ti_(0.01)O_2 has a better thermal safety than LiCoO_2. It is considered that all the improvement should be explained by the particular core-shell morphology of the LiCoO_2/LiCo_(0.99)Ti_(0.01)O_2 sample.