【摘要】 研究了Ti1.0V1.1Mn0.5Nix(x=0.4,0.5,0.6,0.7,0.8,1.0)贮氢合金的相结构和电化学性能。结果表明,所有合金都由两相组成,主相为具有bcc结构的钒基固溶体相,第二相则随着镍含量的增加从C14型Laves相转变成为bcc结构的TiNi基相。合金中的主相晶胞参数随镍含量增加而减小,但C14型Laves相晶胞参数随之增大。SEM照片显示合金中呈树枝晶的主相被三维网络状的第二相包围。电化学性能测试表明,x=0.4的合金电极要比其他合金电极更易活化,但当x=0.7时合金具有最大的放电容量,293 K时放电容量为258.2 mAh.g-1,333 K时放电容量达到了404 mAh.g-1,所有电极放电容量都随温度升高而增大。电极的倍率放电性能随着镍含量的增大得到改善。电化学P-C-T曲线表明,增加镍含量后,合金电极放氢平台压升高。更多还原

【Abstract】 The structure and electrochemical properties of Ti1.0V1.1Mn0.5Nix(x=0.1,0.5,0.6,0.7,0.8,1.0) solid solution alloys were studied.It was found that these alloys consisted of a main solid solution phase with bcc structure and a secondary phase which transferred from C14 type Laves phase into TiNi-based phase with increasing Ni content.Increasing x led to lattice parameter shrinkage of the main phase and TiNi-based phase, while that of C14 type Laves phase changed reversely.SEM shows that these alloys formed dendritic crystal.Ti1.0V1.1Mn0.5Ni0.4 showed easier activation behavior.The maximum discharge capacity was 258.2 mAh·g-1 at 293 K and 404 mAh·g-1 at 333 K for x=0.7.The discharge capacity increased with the increase of temperature.P-C-T isotherms indicated that Ti1.0V1.1Mn0.5Ni0.7 alloy showed higher desorption plateau pressure than Ti1.0V1.1Mn0.5Ni0.4 alloy.更多还原