采用包覆的方法制备出MO/C型复合电极材料,通过X射线衍射(XRD)对复合材料的结构组成进行表征分析,另外通过循环伏安法、计时电位法和交流阻抗技术对复合电极材料在6 M KOH溶液中的电化学电容性能进行考查。结果表明:包覆了过渡金属锰氧...采用包覆的方法制备出MO/C型复合电极材料,通过X射线衍射(XRD)对复合材料的结构组成进行表征分析,另外通过循环伏安法、计时电位法和交流阻抗技术对复合电极材料在6 M KOH溶液中的电化学电容性能进行考查。结果表明:包覆了过渡金属锰氧化物的复合电极材料在0.5 A/g的电流密度下比电容最高可达218.3 F/g。此外,MO/C型复合电极材料表现出较好的功率性能,当电流密度增加到5 A/g,其比电容值达到168.0 F/g,其电容保持率为77.0%,表明这是一种很有前景的电极材料。展开更多
LiFePO4/C composites with good rate capability and high energy density were prepared by adding sugar to the synthetic precursor. A significant improvement in electrode performance was achieved. The resulting carbon co...LiFePO4/C composites with good rate capability and high energy density were prepared by adding sugar to the synthetic precursor. A significant improvement in electrode performance was achieved. The resulting carbon contents in the sample 1 and sample 2 are 3.06% and 4.95%（mass fraction）, respectively. It is believed that the synthesis of LiFePO4 with sugar added before heating is a good method because the synthesized particles having uniform small size are covered by carbon. The performance of the cathodes was evaluated using coin cells. The samples were characterized by X-ray diffraction and scanning electron microscope observation. The addition of carbon limits the particles size growth and enables high electron conductivity. The LiFePO4/C composites show very good electrochemical performance delivering about 142 mAh/g specific capacity when being cycled at the C/10 rate. The capacity fade upon cycling is very small.展开更多
文摘LiFePO4/C composites with good rate capability and high energy density were prepared by adding sugar to the synthetic precursor. A significant improvement in electrode performance was achieved. The resulting carbon contents in the sample 1 and sample 2 are 3.06% and 4.95%（mass fraction）, respectively. It is believed that the synthesis of LiFePO4 with sugar added before heating is a good method because the synthesized particles having uniform small size are covered by carbon. The performance of the cathodes was evaluated using coin cells. The samples were characterized by X-ray diffraction and scanning electron microscope observation. The addition of carbon limits the particles size growth and enables high electron conductivity. The LiFePO4/C composites show very good electrochemical performance delivering about 142 mAh/g specific capacity when being cycled at the C/10 rate. The capacity fade upon cycling is very small.
