无机材料学报 ›› 2010, Vol. 25 ›› Issue (6): 647-652.DOI: 10.3724/SP.J.1077.2010.00647

• 研究论文 • 上一篇    下一篇

电镀镍-钴合金对La-Mg-Ni基贮氢合金电化学性能的影响

丁慧玲1,2, 蒿建生1,3, 朱惜林2,3, 李 媛2, 韩树民1,2, 张静武1   

  1. (1.燕山大学 亚稳材料制备技术与科学国家重点实验室, 秦皇岛 066004; 2.燕山大学 环境与化学工程学院, 秦皇岛 066004; 3.内蒙古稀奥科贮氢合金有限公司, 包头 014030)
  • 收稿日期:2009-12-29 修回日期:2010-02-10 出版日期:2010-06-20 网络出版日期:2010-05-12
  • 基金资助:

    国家自然科学基金(20673093);河北省自然科学基金(B2007000303)

Electrochemical Performance Studies on Nickel-cobalt Electroplated La-Mg-Ni-based Hydrogen Storage Alloys

DING Hui-Ling1,2, HAO Jian-Sheng1,3, ZHU Xi-Lin2,3, LI Yuan2, HAN Shu-Min1,2, ZHANG Jing-Wu1   

  1. (1. State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, China; 2. College of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004, China; 3. Inner Mongolia Rare Earth Ovonic Hydrogen Storage Alloys Corporation Limited, Baotou 014030, China)
  • Received:2009-12-29 Revised:2010-02-10 Published:2010-06-20 Online:2010-05-12

摘要: 为了改善La-Mg-Ni基贮氢合金的循环稳定性和综合电化学性能, 研究了电镀镍-钴合金对La0.88Mg0.12Ni2.95Mn0.10Co0.55Al0.10贮氢合金粉末表面形貌和电极电化学性能的影响. FESEM表明, 电镀处理后合金粉末表面沉积了球状的镍-钴合金颗粒. 电化学性能测试表明, 贮氢合金电极的放电容量、高倍率放电性能和循环稳定性均得到了显著改善. 200周循环时合金电极的容量保持率从未处理合金电极的60%提高到镀覆镍-钴合金的80%, 在放电电流密度1080mA/g下的高倍率放电性能提高了23%. 线性极化曲线和电化学阻抗分析结果显示, 包覆镍-钴合金后贮氢合金电极表面的电荷转移速率加快, 电催化活性提高.

关键词: La-Mg-Ni基贮氢合金, 表面处理, 电镀, 镍-钴合金, 电化学性能

Abstract: In order to improve cycling stability and overall electrochemical properties of La-Mg-Ni-based hydrogen storage alloys, an electroplating treatment was applied on La0.88Mg0.12Ni2.95Mn0.10Co0.55Al0.10 alloy powders. The effect of cobalt-nickel coating on the morphological and electrochemical properties was studied. FESEM results show that spherical nickel-cobalt alloy particles are deposited on the surface of the alloys. Electrochemical tests indicate that the maximum discharge capacity, the cycling stability and the high rate dischargeability (HRD) are remarkably improved. After 200 charge/discharge cycles, the capacity retention rate increases from 60% (uncoated) to 80% (nickel-cobalt coated). The HRD at 1080mA/g rises by 23% for the nickel-cobalt coated alloy electrodes. Linear polarization and Electrochemical Impedance Spectroscope (EIS) results reveal that the surface of alloy electrodes with cobalt-nickel coatings is more catalytic for the electrochemical charge transfer reactions.

Key words: La-Mg-Ni-based hydrogen storage alloy, surface treatment, electroplating, nickel-cobalt alloy, electrochemical characteristics

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