磷酸铁锂在饱和硝酸锂溶液中的电极过程动力学  

Kinetics of Electrode Processes of LiFePO_4 in Saturated Lithium Nitrate Solution

作　　者：黄可龙[1] 杨赛[1] 刘素琴[1] 王海波[1] 

机构地区：[1]中南大学化学化工学院,长沙410083

出　　处：《物理化学学报》2007年第1期129-133,共5页Acta Physico-Chimica Sinica

基　　金：国家教育部博士基金(50201014)资助项目

摘　　要：利用循环伏安法(CV)、充放电测试和恒电位间隙滴定技术(PITT)研究了LiFePO4在饱和LiNO3溶液中的电极过程动力学.研究结果表明,LiFePO4在饱和LiNO3溶液中具有良好的电化学可逆性,其首次放电比容量达116.2mAh·g-1,首次充放电效率达92%.CV法估算出氧化峰和还原峰处锂离子在LiFePO4中的扩散系数分别为4.3×10-11和3.8×10-11cm2·s-1.采用PITT测定出锂离子在LiFePO4中的扩散系数随电位的变化规律,其在充电平台附近达到最小值5.5×10-11cm2·s-1.Kinetics of electrode processes of LiFePO, in saturated LiNO3 solution was investigated by analyses of cyclic voltammetry （CV）, charge/discharge test, and potentiostatic intermittent titration （PITT）. The results showed that LiFePO, had good electrochemical reversibility in saturated LiNO3 solution. The first discharge capacity was about 116.2 mAh·g-l, and its charge/discharge efficiency was 92%. The lithium diffusion coefficients, corresponding to anodic peak and cathodic peak in LiFePO,, obtained from CV were 4.3×10^-11 cm^2·s-^1 and 3.8×10^-11 cm^2· s^-1. The lithium diffusion coefficients obtained from PITF varied with potentials, and the lowest value was about 5.5×10^-11cm^2 · s^-1, coinciding with the voltage plateau region in the charge curves.

关 键 词：水溶液锂离子电池 LIFEPO4 循环伏安法 恒电位间隙滴定技术 扩散系数 

分 类 号：TM912[电气工程—电力电子与电力传动]