초록 |
There are many cathode materials for Li ion batteries such as LiCO2, LiNiO2, LiMnO4, LiFePO4, etc.. Of these materials, many works have focused on the improvement of the performance of LiNiO2 due to low cost and high energy density. However, the main problems of LiNiO2 are low reproducibility, short life and low stability at high temperature. In order to solve these problems, the substitution of Co or Al for Ni has been investigated. Another problem of LiNiO2 is that its basicity is higher than that of LiCoO2. Therefore, Li2CO3 on surface of LiNiO2-based materials during storage is easily formed as reacting with H2O and CO2 in the air at room temperature. This formation of Li2CO3 on the surface of LiNiO2-based materials is the main source of poor storage property of LiNiO2-based materials. Li2CO3 on the surface also causes gas evolution during the battery operation and much lower capacity. In this study, we prepared bare and ZrO2-coated LiNi0.8Co0.2O2 powders by flame spray pyrolysis of emulsion and investigated the effect of coated layer on the suppression of formation of Li2CO3 on the surface of LiNi0.8Co0.2O2 powder. |