锂离子电池正极材料Li2FeSiO4/C的改性研究

Research on Modification of Cathode Material Li_2FeSiO_4/C for Lithium-ion Battery

采用改进的溶胶-凝胶法合成了Li2Fe1-xMnxSiO4/C(x=0,1/4,1/3,1/2)复合材料.用X射线衍射(XRD)、拉曼光谱和扫描电子显微镜(SEM)对材料的结构和形貌进行了表征.通过恒流充放电对材料的电化学性能进行了测试.结果表明,在室温、1.5～4.8 V电压范围内,于C/16倍率下进行充放电测试时,Li2Fe3/4Mn1/4SiO4/C具有较高的首次放电比容量(201.0 mA.h/g),具有良好的电化学性能.

Li2Fe1-xMnxSiO4/C（x =0,1/4,1/3,1/2） cathodes materials were synthesized by modified sol-gel method.The structure and morphology of the materials were characterized by XRD,Raman scattering spectra and SEM.The electrochemical properties of the materials were tested by constant-current cyclic testing.The results show that Li2Fe3/4 Mn1/4 SiO4 /C has a good electrochemical performance.The first dis-charge capacity of Li2Fe3/4Mn1/4SiO4/C cathode material at room temperature reaches 201.0 mA.h/g when cycled at C/16 between 1.5 and 4.8 V.