Fe_2P对LiFePO_4/C复合材料性能的影响(英文)  

Influence of Fe_2 P on the Performance of LiFePO_4/C Composite Material

作　　者：易惠华[1] 戴永年[1] 胡成林[1] 姚耀春[1] 

机构地区：[1]昆明理工大学 材料与冶金工程学院∥真空冶金国家工程实验室,云南昆明650093

出　　处：《中山大学学报（自然科学版）》2009年第S2期158-160,共3页Acta Scientiarum Naturalium Universitatis Sunyatseni

摘　　要：采用固相法合成LiFePO_4和LiFePO_4/C复合材料,研究了蔗糖分解的碳包覆对LiFePO_4材料性能的影响。XRD检测纯LiFePO_4为单一的橄榄石相,而LiFePO_4/C复合材料中出现高导电物质Fe_2P相;SEM显示样品的粒径均在1μm以下,包覆碳样品的晶粒更小,但出现团聚现象。此方法合成的纯LiFePO_4初始容量高达136.6mAh/g.Fe_2P的存在使LiFePO_4材料的大电流放电能力得到提高。Pure LiFePO_4 and LiFePO_4/C composite cathode materials were synthesized by solid-state method and effect of carbon coating on the performance of LiFePO_4 was studied.The XRD pattern of the pure LiFePO_4 shows a single-phase olivine,but the ones of LiFePO_4/C composite materials show a impurity phase Fe_2P with high electronic conductivity.From the SEM images,it can be seen that the particle sizes of the samples are less than 1μm.Though the carbon-coated samples have smaller particle sizes,some of them are in the form of particle agglomerates.The first cycle discharge capacity of the pure LiFePO_4 reaches 136.6 mAh/g,then the electro-conductive Fe_2P among LiFePO_4/C increases the performance of them at high rate charge/discharge.

关 键 词：锂离子电池 正极材料 磷酸铁锂 电化学性能 

分 类 号：TM912.9[电气工程—电力电子与电力传动]