北京科技大学学报2013，Vol.35Issue(1)：78-84,7.
高容量正极材料Li[Li0.17Mn0.58Ni0.25]O2的倍率性能
Rate capability of Li[Li0.17Mn0.58Ni0.25]O2 as high-capacity cathode materials
摘要
Abstract
A carbonate coprecipitation method was used to synthesize Li[Li0.17Mn0.58Ni0.25]O2 samples with different morphologies via controlling the crystal process. The Li[Li0.17Mn0.58Ni0.25]O2 samples were characterized by X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), field emission scanning electron microscopy (FESEM), galvanostatic charge-discharge testing, and electrochemical impedance spectroscopy (EIS). It is found that the Li[Li0.17Mn0.58Ni0.25]O2 samples, with high crystallinity, can all be indexed as a α-NaFeO2 phase (space group R3m). Moreover, the sample with the hexagonal primary particles aggregated along with the long axis shows a much better rate capability than the other. Li[Li0.17Mn0.58Ni0.25]O2 delivers the initial discharge capacities of 205.4, 195.5 and 158.5 mA·h·g-1, in the voltage range of 2.5~4.8 V at the rates of 0.5C, 1.0C and 3.0C, respectively. After 100 cycles, the discharge capacities are 203.5, 187.2and 151.2 mA·h·g-1, which correspond to 99%, 96% and 95% retention of their initial capacities. The special aggregated morphology of Li[Li0.17Mn0.58Ni0.25]O2 particles contributes to the reduced charge transferring impedance and the improved rate capability. Additionally, the electrochemical properties of the materials in different potential windows were also comparatively studied.关键词
锂电池/正极材料/倍率性能/循环性能Key words
lithium batteries/ cathode materials/ rate capability/ cycling performance分类
信息技术与安全科学引用本文复制引用
高敏,连芳,仇卫华,杨王玥..高容量正极材料Li[Li0.17Mn0.58Ni0.25]O2的倍率性能[J].北京科技大学学报,2013,35(1):78-84,7.基金项目
国家高技术发展计划资助项目(2009AA03Z226) （2009AA03Z226）
国家自然科学基金资助项目(50702007) （50702007）
中央高校基本科研业务费资助项目(FRF-MP-12-005B) （FRF-MP-12-005B）
