摘要
本文对气态粉化后A2B7型贮氢合金La0.75Mg0.25Ni3.44Al0.06进行化学镀不同厚度Ni包覆处理。通过SEM观察,结果表明,包覆处理后镀层镍为球形颗粒且均匀弥散于合金表面。电化学测试结果表明,表面包覆镍处理的A2B7型合金电极放电容量有所降低,而循环稳定性有所提高。线性极化扫描和电化学阻抗谱等分析结果表明,表面包覆Ni处理后增大了合金电极的交换电流密度(I0),减小了电化学阻抗,改善了合金电极的动力学性能。
The nickel coating by chemical plating on the La0.75Mg0.25Ni3.44Al0.06 hydrogen storage alloy electrode was systematically studied in this paper.The results of SEM showed that some global grain covere on the surface of alloys.The section opticmicroscope picture of powder alloy showed that the nickel coating was very symmetrical.The electrochemical results showed that,after nickel coating,the cyclic stability of the alloy electrodes was some what improved,while the maximum discharge capacity was reduced.The results of linear polarization and impedance spectroscopy show that hydrogen storage alloys coated could increase exchange current density I0,reduce electrochemical reaction resistance,so the high-rate discharge performance of the coated electrode is successfully improved.
出处
《金属功能材料》
CAS
2012年第1期11-15,共5页
Metallic Functional Materials
关键词
A2B7
型贮氢合金
化学镀镍
电化学性能
A2B7 type hydrogen storage alloy
chemical nickel plating
electrochemical properties
