Jiewu Zhu

Electrochemical Properties of Co-Free Ml0.8Mg0.2Ni3.4Al0.4 Hydrogen Storage Alloy Ballmilled with Ni and Mo

In order to improve the electrochemical properties of Co-free Ml 0.8 Mg 0.2 Ni 3.4 Al 0.4 alloy, the alloy powder was ballmilled with Ni and Mo powders, respectively. The surface morphology and composition of the treated powder were examined by metallograph and X-ray photoelectron spectrum. The electrochemical capacity, rate dischargeability, and cycle life were investigated. It was found that the surface of the alloy powder was coated with a Ni or Mo film and the surface modification enhanced the electrochemical capacity, high-rate dischargeability, and cycle life. The Ni-coated alloy electrode had the highest electrochemical capacity of 325 mAh/g and high-rate dischargeability of 59.4%, while the Mo-coated alloy electrode exhibited the best cycle life. An electrochemical capacity of 320 mAh/g was achieved, and 85% of the initial capacity remained after 300 cycles for the Mo-coated alloy, which shows a great potential for applications for Ni-MH batteries.