Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9759254 | International Journal of Hydrogen Energy | 2005 | 8 Pages |
Abstract
In order to compare the effects of the preparation techniques on the electrochemical performances of Co-free AB5-type hydrogen storage alloys, the Co-free AB5-type LaxMm1-x(NiMnSiAlFe)4.9(x=0,0.45,0.75,1.0) hydrogen storage alloys were prepared by casting and rapid quenching. The phase structures and microstructures of the as-cast and quenched alloys were analyzed by XRD, SEM and TEM. The effects of the rapid quenching on the microstructures and electrochemical performances of the specimen alloys were investigated in detail. The obtained results show that, when the amount of the La substitution x=0.75, the discharge capacity of the as-quenched alloy with quenching rate of 10Â m/s is 292Â mAÂ h/g with charge-discharge current density of 60Â mA/g, the capacity retaining rate (Rh) is 61.2% after 300 charge-discharge cycles with current density of 300Â mA/g. When the amount of the La substitution x=1, the discharge capacities of the as-quenched alloy with quenching rate of 10 and 16Â m/s are 300 and 292Â mAÂ h/g, and the capacity retaining rates (Rh) are 62.3% and 65.0%, respectively.
Related Topics
Physical Sciences and Engineering
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Authors
Yang-huan Zhang, Guo-qing Wang, Xiao-ping Dong, Shi-hai Guo, Xin-lin Wang,