制粉工艺对贮氢电极高倍率放电性能影响的动力学分析  

Kinetics Analysis on the High Rate Discharge Performance of Hydride Electrode under Different Milling Condition

作　　者：刘诗月[1] 刘开宇[1] 张平民[1] 

机构地区：[1]中南大学化学化工学院,湖南长沙410083

出　　处：《金属功能材料》2004年第4期5-9,共5页Metallic Functional Materials

摘　　要：研究了干法、湿法和湿法加添加剂三种制粉工艺条件下得到的贮氢合金粉末电极的交换电流密度、电化学反应电阻、阳极极化和阴极极化 ,从动力学的角度对贮氢电极高倍率放电性能进行了分析。结果表明 :湿法制粉工艺能大大的提高贮氢电极的交换电流密度 ,从干法制粉的 85 6 4mA·g-1增加到湿法加添加剂工艺的 16 6 99mA·g-1;降低电极电化学反应电阻 ,采用干法、湿法或湿法加添加剂制粉工艺贮氢电极的反应电阻分别为 0 30Ω、0 2 4Ω和 0 15Ω ;湿法加添加剂制粉时氢在α相中的扩散系数Dα 差不多达到干法制粉的二倍 ;湿法加添加剂的条件下 ,阴极极化和阳极极化均达到最小。表明湿法制粉工艺能有效地提高贮氢合金电极的电化学反应活性 ,从而提高贮氢合金电极吸。The exchange current density, electrochemical reaction resistance, anode and cathode polarization of electrode of hydrogen storage alloy powder prepared at dry, wet and wet method with additive conditions were studied, and the high rate discharge performance of hydride electrode was analyzed from the point of kinetic view. The results shown that the exchange current density of hydride electrode can be distinctly increased with wet method increasing from 85.64mA·g -1 of dry method to 166.99mA·g -1 of wet method with additive. The electrochemical reaction resistance can be decreased adopting wet method,the reactive resistance of hydride electrode are 0.30Ω,0.24Ω and 0.15Ω respectively corresponding to dry method,wet method and wet method with additive. The diffusing coefficient D α of hydrogen in α-phase of hydride electrode under wet method with additive is almost double to that under dry method technique and both cathodic and anodic polarization reach the least under wet method with additive. All of the above indicate that the wet method can effectively improve the electrochemical reaction activation and the kinetics performance of hydrogen absorbing and releasing processes of hydride electrode.

关 键 词：贮氢合金 粉碎 动力学分析 极化 高倍率放电性能 制粉工艺 合金粉末 

分 类 号：TM911[电气工程—电力电子与电力传动]