【摘要】 <正>锂离子电池的正极活性材料主要为锂化复合氧化物,如LiCoO2、LiNiO2、LiMn2O4,平均工作电压均达4V(vsLi/Li+)左右[1]。以LiCoO2为正极活性材料,碳材料为负极活性材料的锂离子电池,由于具有容量更多还原

【Abstract】 The solid diffusion coefficient of lithium-ion in LiCoO2 cathode material has been investigated by the capacity intermittent titration technique (CITT) at different voltages and at different charge/discharge cycles. By SEM, XRD and FTIR techniques, the structure of LiCoO2 was studied before and after charge-discharge cycles, and the relationship between solid diffusion coefficient and crystal structure was further discussed. CITT results show that the value of Li+ solid diffusion coefficient of LiCoO2 is about 10-12 cm2·s-1. During the whole charge-discharge cycles, the Li+ solid diffusion coefficient decreased within the voltage of 4.0~4.3 V, which is attributed to the change of the structure of LiCoO2.更多还原