OP制备的LiFePO_4/C的性能及碳的作用  

The performance of LiFePO_4/C synthesized from OP and the effect of carbon

作　　者：甘晖[1] 连锦明[1] 童庆松[1] 

机构地区：[1]福建师范大学化学与材料学院,福建福州350007

出　　处：《电池》2008年第6期339-342,共4页Battery Bimonthly

基　　金：福建省教育厅基金(JA03030);福建省自然科学基金(E0110021)

摘　　要：以聚乙二醇辛基苯基醚(OP)为碳源,用固相反应法合成了LiFePO4/C。XRD分析的结果表明,样品的主要物相是橄榄石相LiFePO4。OP用量为22.55%、合成温度为625℃时,制备样品的放电比容量最高,以1.0C(0.50 mA/cm2)、0.5C(0.25mA/cm2)和0.1C(0.05 mA/cm2)放电时,第10次循环的放电比容量分别为93.0 mAh/g、132.6 mAh/g和160.0 mAh/g。由OP分解得到的碳改变了反应的动力学,抑制了晶粒的增长,提高了样品的放电比容量;炭黑直接提高了电极的导电能力。LiFePO4/C was synthesized by solid state reaction method using polyethylene glycol oetylphenyl ether （OP） as the carbon source. The XRD analysis results showed that the main phase of the sample was olivine phase LiFePO4. The sample using 22.55% OP and synthesized at 625 ℃ had the highest specific discharge capacity, the specific discharge capacity at the 10th cycle was 93.0 mAh/g, 132.6 mAh/g and 160.0 mAh/g at 1.0 C（0.50 mA/cm^2） ,0.5 C（0.25 mA/cm^2） and 0. 1 C（0.05 mA/ cm^2） discharge, respectively. The carbon decomposed from OP changed the kinetics of the reaction, restrained the growth of crystal,improved the specific discharge capacity of the sample. Carbon black improved the conductivity of electrode directly.

关 键 词：锂离子电池 LIFEPO4 动力学 聚乙二醇辛基苯基醚(OP) 

分 类 号：TM912.9[电气工程—电力电子与电力传动]