Ti_(0.4)Zr_(0.1)V_(1.1)Mn_(0.5)Ni_(0.4)Cr_x(x=0,0.1,0.2,0.3)储氢合金的微观结构和电化学性能  

Microstructure and Electrochemical Properties of Ti_(0.4)Zr_(0.1)V_(1.1)Mn_(0.5)Ni_(0.4)Cr_x(x=0,0.1,0.2,0.3)Alloys

作　　者：杭州明 邴智刚 许恒 翁文祥 

机构地区：[1]浙江省质量检测科学研究院,浙江杭州310023

出　　处：《材料科学与工程学报》2014年第1期52-57,共6页Journal of Materials Science and Engineering

摘　　要：采用XRD、SEM-EDS等方法对Ti0.4Zr0.1V1.1Mn0.5Ni0.4Crx(x=0,0.1,0.2,0.3)储氢合金的微观结构及电化学性能进行了表征。XRD分析结果表明Ti0.4Zr0.1V1.1Mn0.5Ni0.4Crx(x=0,0.1,0.2,0.3)储氢合金由BCC结构的V基固溶体主相和少量的C14Laves第二相组成。SEM-EDS分析结果表明,V基固溶体主相为树枝晶结构,C14Laves相呈网格状沿着主相晶界析出。电化学测试结果表明,Ti0.4Zr0.1V1.1Mn0.5Ni0.4Crx(x=0,0.1,0.2,0.3)氢化物电极在303K下,随Cr含量的增加,最大放电容量分别为574.6mAh/g、418.8mAh/g、368.8mAh/g和322.9mAh/g。当x=0.3时,合金电极在333K下的最大放电容量达到了824.1mAh/g。Cr的添加显著提高了合金电极的高倍率放电性能和循环寿命,40次充放电循环后Ti0.4Zr0.1V1.1Mn0.5Ni0.4Cr0.3合金电极的容量保持率为62.3%。Microstructure and electrochemical properties of Ti0.4Zr0.1V1.1Mn0.5Ni0.4Crx(x=0,0.1,0.2,0.3)alloys have been investigated.Results of XRD and SEM-EDS analyses show that all alloys are composed of a major V-based solid solution phase with body-centered-cubic structure and a minor C14Laves phase with hexagonal structure.The V-based solid solution phase appears as dendrite with C14Laves phase precipitating along its grain boundary,forming a three-dimensional network.Effect of Cr addition on the electrochemical properties of Ti0.4Zr0.1V1.1Mn0.5Ni0.4Crx(x=0,0.1,0.2,0.3)alloys was studied by electrochemical method.With increasing Cr content from x=0to x=3,the maximum discharge capacities of Ti0.4Zr0.1V1.1Mn0.5Ni0.4Crx(x=0,0.1,0.2,0.3)alloy electrodes at 303Kare 574.6mAh/g,418.8mAh/g,368.8mAh/g and 322.9 mAh/g,respectively.It is emphasized that high discharge capacity of 824.1mAh/g is obtained at x=0at 333K.The addition of Cr noticeably improves the high rate discharge performance and durability of alloy electrodes.The capacity retain rate of 62.3%is attained at x=3after 40charge-discharge cycling.Among the alloys studied,Ti0.4Zr0.1V1.1Mn0.5Ni0.4Cr0.1 alloy has the best overall electrochemical performance.

关 键 词：MH/NI电池 V基固溶体 Cr添加 微观结构 电化学性能 

分 类 号：TG139.7[一般工业技术—材料科学与工程]