混合稀土贮氢合金 Mm_x(Ni3.55Co0.75Mn0.4Al0.3)化学配比x对电化学性能的影响  

Effect of the stoichiometric ratio on electrochemical property of Mm x (Ni 3.55 Co 0.75 Mn 0.4 Al 0.3 ) hydrogen storage alloys

作　　者：王超群[1] 靳红梅[1] 李国勋[1] 应启明[1] 王宁[1] 

机构地区：[1]北京有色金属研究总院

出　　处：《电源技术》1998年第4期158-160,共3页Chinese Journal of Power Sources

基　　金：国家自然科学基金

摘　　要：研究了成分为Ｍｍｘ（Ｎｉ３．５５Ｃｏ０．７５Ｍｎ０．４Ａｌ０．３）的贮氢合金（０．８０≤ｘ≤１．２５，Ｍｍ为混合稀土金属元素Ｌａ，Ｎｄ，Ｐｒ）化学配比ｘ对其电化学性能的影响。在ｘ＝０．８０～０．９５范围内和电流密度为０．２Ａ／ｇ－１下，放电比容量随合金晶胞体积的增大而增加。在相对贫稀土的混合稀土合金中，由于形成了相对不稳定的氢化物相，因而具有较大的电催化活性以及较高的放电比容量，如ｘ＝０．８０，０．９０和０．９５的贮氢合金。采用适当化学配比ｘ的混合稀土贮氢合金，电化学性能可以得到很大改善，同时价格也较便宜，具有实用前景。Effect of stoichiometric ratio on the electrochemical property of negative electrodes was studied for alloys with composition of Mm x (Ni 3.55 Co 0.75 Mn 0.4 Al 0.3 ) (Mm=misch metal ,0.80≤x≤1.25). The discharge capacity at a current density of 0.2 A·g -1 increased with increase of unit cell volume of the alloy in the range of x=0.80～0.95. The high electrocatalytic activity and high discharge capacity could be obtained due to the formation of relatively unstable hydride in Mm poor non stoichiometric alloys (x=0.80～0.95). The electrochemical property of Mm x (Ni 3.55 Co 0.75 Mn 0.4 Al 0.3 ) alloy electrode was greatly improved by means of adjusting the stoichiometric ratio x, while it is to have prospective application due to low cost.

关 键 词：稀土 贮氢合金 化学配比 放电比 碱性蓄电池 

分 类 号：TG139.7[一般工业技术—材料科学与工程] TM912.205[金属学及工艺—合金]