초록 |
Li-excess Mn-based materials with a formula Li1+xMnyMzO2, often written as xLi4/3Mn2/3O2(1x)LiMO2, have demonstrated a high discharge capacity as cathode material, higher than common materials such as LiCoO2. However, this material has low discharge rate and poor cyclability. Recently, It was introduced to be enhanced the rate ability, as treat with (NH4)2SO2. But the improvement of cycle performance was not significant. So, in order to improve the cyclability, our purpose is the study of coating effects by Al2O3 for Li[Li0.2Co0.13Ni0.13 Mn0.54]O2 already treated with (NH4)2SO4. We measured the electrochemical performance of Li[Li0.2Co0.13Ni0.13Mn0.54] O2 with 2032-type coin cells. The Li[Li0.2Co0.13Ni0.13Mn0.54]O2 coated by Al2O3 after treating by (NH4)2SO4 showed the improvement of cycle performance and the enhancement of discharge capacity after 20 cycle. |