合成温度对Li_2FeSiO_4/C电化学性能的影响

Effect of synthesis temperature on the electrochemical performance of Li_2FeSiO_4/C

采用球磨掺碳及固相法合成锂离子电池正极材料Li2FeSiO4/C,研究了合成温度对材料结构和电化学性能的影响。用X射线衍射(XRD)、扫描电镜(SEM)对材料的结构与形貌进行了表征;并对不同焙烧温度下合成的Li2FeSiO4/C材料的电化学性能进行了研究。结果表明,650℃合成的Li2FeSiO4/C电化学性能最佳,在C/16的倍率下首次放电容量达到144.8mAh/g,10次循环后容量仍保持有136.5mAh/g。

Li2FeSiO4/C was synthesized at different temperature by solid-state reaction combining with ball-milling of the precursor and sucrose. The crystalline structure, morphology of particles and charge/discharge performance of Li2FeSiO4/C were analyzed by X-ray diffraction （XRD）, scanning electron microscope（SEM）, and electrochemical measurement, respectively. Electrochemical tests show that the first specific discharge capacity of the Li2FeSiO4/C synthesized at 650℃ is 144.8mAh/g, and the discharge capacity remains 136.5mAh/g after 10 charge-discharge cycles.