正极材料LiNi_(0.7)Co_(0.3)O_2合成条件及电化学性能研究

Research on the synthesis conditions and electrochemical properties of LiNi_(0.7)Co_(0.3)O_2 cathode materials

采用溶胶凝胶法制备了LiNi0.7Co0.3O2。结果表明,煅烧温度为800℃、时间为12 h、Li/(Ni+Co)=1.05的正极材料LiNi0.7Co0.3O2具有α-NaFeO2型的六方晶体结构,在0.1 C下,首次充放电比容量分别为218.0 mAh/g和190.2 mAh/g,首次充放电效率为87.2%,经过20次循环仍有171.5 mAh/g,容量保持率为90.3%。

LiNi0.7Co0.3O2 Were prepared by the sol-gel method. The results showed that all the samples have α-NaFeO2-type hexagonal layered structure and show no impurity-related peaks of sample. The LiNi0.7Co0.3O2 with Li/（ Ni ＋ Co） = 1.05 synthesized at 800℃ for 12 h in air displayed the best electro- chemical performance, at 0. 1 C, the initial charge and discharge capacity was 218. 0 mAh/g and 190.2 mAh/g, respectively ; and the initial charge-discharge efficiency was 87.2%. After 20 cycles, this sample remained 171.5 mAh/g of discharge capacity,the capacity retention rate was 90.3%.