Performance tests on metal hydride based hydrogen storage devices

In this manuscript, the performance tests on the metal hydride based hydrogen storage devices employing Mg + 30% MmNi5 and MmNi4.08Co0.2Mn0.62Al0.1 are presented. Hydrogen storage performances of Mg + 30% MmNi5 were investigated in the absorption and desorption temperatures ranges of 120–150 °C and 300–350 °C, respectively. The respective ranges for MmNi4.08Co0.2Mn0.62Al0.1 are 30–180 °C and 40–60 °C. For both the hydrides, supply pressures were varied from 10 to 30 bar. The maximum observed hydrogen storage capacities of Mg + 30% MmNi5 at 20 bar supply pressure and 150 °C absorption temperature and MmNi4.08Co0.2Mn0.62Al0.1 at 30 bar supply pressure, and 30 °C absorption temperature are 2.5 wt% and 1.2 wt%, respectively. For both the hydrides, the hydrogen storage capacities and the hydrogen absorption rates were found to increase with supply pressure. For a given supply pressure of 20 bar, the hydrogen storage capacity of Mg + 30% MmNi5 was found to increase from 1.94 wt% at 120 °C to 2.5 wt% at 150 °C absorption temperature. The effect of supply pressure on the hydrogen storage capacities of Mg + 30% MmNi5 at 150 °C absorption temperature and MmNi4.08Co0.2Mn0.62Al0.1 at 30 °C absorption temperature was limited to 20 bar and 30 bar, respectively.