Effect of Calcination Temperature on the Structure and Electrochemical Performance of LiNi0.4Co0.2Mn0.4O2

LiNi0.4Co0.2Mn0.4O2, as the cathode materials for lithium ion battery, were prepared from the precursors, Ni0.4Co0.2Mn0.4 (OH)2 which were synthesized by chemical co-precipitation method. The crystal structure and morphology of the prepared powders have been characterized by X-ray diffraction and SEM, respectively. The results show that Li+/Ni2+ cation mixing decreases with increase of calcination temperature in the range of 700-900°C.The lower degree of cation mixing can improve the transfer of Li ions and lead to layered structure more stable. The discharge capacity and the capacity retention rate of the material is strongly impacted by the reaction temperature.The powders sintered at 900°C show the best electrochemical performance and the initial discharge capacity is 148.3mA·h/g, after 40 cycles, the capacity retention rate is 93.9%.