化学镀Ni-Co-P合金对Mm(NiCoAlMn)_5贮氢合金电极动力学性能的影响

Effect of Ni-Co-P Coating on Kinetic Properties in Hydride Electrode for Mm(NiCoAlMn)_5 Hydrogen Storage Alloy

通过电化学方法 ,研究了化学镀Ni Co P合金对Mm(NiCoAlMn) 5 五元稀土贮氢合金电极动力学性能的影响。研究表明 ,引入很少量(1%～ 2 % )Co的Ni Co P合金镀层可有效地提高MH电极的交换电流密度i0 、极限电流密度iL 及α相中氢的扩散系数Dα(H ) ;还研究了化学镀Ni Co P合金对稀土贮氢合金电极循环伏安 (CV)曲线和阴、阳极极化曲线及对称因子 β的影响 。

The effect of electroless plated Ni Co P alloy coating on the kinetic properties of Mm(NiCoAlMn) 5 rare earths based hydride electrode was investigated by electrochemical techniques. The results indicate that the kinetic properties of MH electrode, including exchange current density i 0, limiting current density i L, and diffusion coefficient of hydrogen in α phase D α(H) are improved markedly. These improvements of kinetic properties lead to the increase of anodic peak current and peak integration area of MH electrode modified by Ni Co P alloy in CV curve as well as the decrease of overpotential of anodic and cathodic polarization.