14.Fe部分替代Mn对AB5型储氢合金结构与电化学性能的影响

摘 要： 采用感应熔炼法制备了MlNi         _3.8Mn         _0.95-xAl         _0.15Fe         _x （x=0         ，0.15         ，0.30         ，0.45         ，0.60         ） 系列 储氢合金 ，采用 X 射线衍射仪对其相组成及结构进行测试与分析，采用双电极模拟电池测试系统对其电化学性能进行表征。结果表明： Fe 部分替代 Mn 后并未改变合金的相结构，随 Fe 替代量的增大合金的晶胞体积逐渐减小； Fe 替代后不同程度的恶化了合金的活化性能，并使合金的放电容量部分降低；合金的循环稳定性随着 Fe 替代量的增加先增大后减小，当 x=0.30 时循环稳定性最好， 300 周的容量保持率为 74.63% ；但是合金的倍率性能却随着 Fe 替代量的增加逐渐降低。

Effect of Partial Substitution of Mn by Fe on the Phase Structure and Electrochemical Property of AB₅ Type Hydrogen Storage Alloys

Zhao Jun-jun^1,2 Feng Dianchen ^3,1 Hu Feng¹Cai Ying¹ Wang Xitao³

(1. School of Materials and Metallurgy, Inner Mongolia University of Science and Technology, Inner Mongolia, Baotou 014010, China;

2. Inner Mongolia Rare Earth Ovonic Metal Hydride Co.Ltd, Inner Mongolia, Bao Tou 014030;

3.State Key Laboratory for Advanced Metals and Materials,University of Science and Technology Beijing,Beijing 100083,                                     China                 )

Key words: hydrogen storage alloys; phase structure; electrochemical properties；Cycle stability

Abstract: A series of AB₅ type MlNi_3.8Mn_0.95-xAl_0.15Fe_x （x=0，0.15，0.30，0.45，0.60） hydrogen storage alloys were prepared by vacuum induction melting. Phase composition and structure were characterized by XRD, and the electrochemistry performance were tested and analyzed by two-electrode cell simulation test system. X-ray diffraction (XRD) indicates that the bulk phase structure of the alloy is not changed by the partial substitution of Fe for Mn.The cell volume (V) decreased with increasing Fe content.The activation of performance has different degrees of deterioration, and the maximum discharge capacitydecrease with increasing x. The cycle stability of the alloys first increase then decrease with increasing Fe content. The alloy(x=0.30)shows the best cycle stability, whenthe capacity retention of the alloy electrodes reached 74.63% at the 300th cycle (S₃₀₀).But the high rate discharge performance of the alloy is gradually reduced with the increase of the amount of Fe substitution.