关键词: 锂离子电池, 富锂正极材料, Li1.2Ni0.17Co0.07Mn0.56O2, 喷雾干燥法, 共沉淀法, 固相法

Abstract: Lithium rich Li1.2Ni0.17Co0.07Mn0.56O2 cathode materials for lithium ion batteries were synthesized by three different methods：a spray-drying method, a co-precipitation method and a solid-state reaction method. Electrochemical tests show that the sample prepared by the spray-drying method presents the best cycling performance with discharge capacity of 153.4 mA?h?g－1 at 1 C rate. No degradation was observed after 50 cycles. While the samples prepared by the co-precipitation method and the solid-state reaction method delivered the capacity of 133.5 mA?h?g－1 and 123.6 mA?h? g－1, respectively, after 50 cycles under 1 C rate charge-discharge. The results of ICP measurements indicate that only the composition of the sample prepared by the spray-drying method can exactly consist with the formula Li1.2Ni0.17Co0.07Mn0.56O2. Furthermore, FSEM observation shows that the sample by spray-drying method has smaller particle size with even particle size distribution, which would benefit its electrochemical performance.

Key words: Lithium-ion battery, Lithium rich cathode material, Li1.2Ni0.17Co0.07Mn0.56O2, spray- drying method, co-precipitation method, solid-state reaction method