摘要
为改善富锂材料的电化学性能,使用Li_3VO_4对富锂锰基材料Li_(1.2)Ni_(0.13)Co_(0.13)Mn_(0.54)O_2进行湿法包覆。对样品进行表征和电化学性能测试,结果表明,包覆工艺不会破坏富锂层状材料的结构;包覆物明显改善样品的电化学性能,其中3%包覆量的样品综合性能最好,首次放电比容量为243.2 m Ah/g,库伦效率70.9%;在1C下循环50次后,容量保持率为87.2%。
In order to improve electrochemical properties of Li-rich cathode materials,Li_(1.2)Ni_(0.13)Co_(0.13)Mn_(0.54)O_2 was wet-coated with Li_3VO_4 to obtain several samples with different coating amounts,which were then characterized and taken for testing electrochemical properties. Results showed that the coating process does not destroy the structure of the Li-rich layered material,and the coating material can obviously improve the electrochemical properties of the samples. It is shown that the sample with 3% coating presented the best comprehensive performance,with the first discharge capacity of 243. 2 m Ah/g and the coulombic efficiency of 70.9%. After 50 cycles at 1 C,the capacity retention rate was 87.2%.
引文
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