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High temperature metal hydrides as heat storage materials for solar and related applications.

Felderhoff M, Bogdanović B - Int J Mol Sci (2009)

Bottom Line: High temperature metal hydrides offer high heat storage capacities around this temperature.Based on Mg-compounds, these hydrides are in principle low-cost materials with excellent cycling stability.Relevant properties of these hydrides and their possible applications as heat storage materials are described.

View Article: PubMed Central - PubMed

Affiliation: Max-Planck Institut für Kohlenforschung, Mülheim/Ruhr, Germany. felderhoff@mpi-muelheim.mpg.de <felderhoff@mpi-muelheim.mpg.de>

ABSTRACT
For the continuous production of electricity with solar heat power plants the storage of heat at a temperature level around 400 degrees C is essential. High temperature metal hydrides offer high heat storage capacities around this temperature. Based on Mg-compounds, these hydrides are in principle low-cost materials with excellent cycling stability. Relevant properties of these hydrides and their possible applications as heat storage materials are described.

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Related in: MedlinePlus

Crystal unit cell of Mg2FeH6; Mg-atoms are shown in blue, Fe-atoms are located in the centers of the octahedrons.
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f7-ijms-10-00325: Crystal unit cell of Mg2FeH6; Mg-atoms are shown in blue, Fe-atoms are located in the centers of the octahedrons.

Mentions: As it can be seen in Figure 7, Mg2FeH6 is composed of Mg2+ cations and FeH64- anions in the form of octahedrons. In the center of the octahedrons is located a Fe atom, which is surrounded by six covalently bound H atoms. Alternatively to the high pressure method, Mg2FeH6 can be synthesized by reactive mechanical alloying of Fe and Mg elemental powders in a hydrogen atmosphere at room temperature [24–26]. The gravimetric hydrogen content of Mg2FeH6 is 5.5 wt.%. The volumetric hydrogen density reaches 150 kg m−3 which is double of the density of liquid hydrogen (70 kg m−3). The advantage of Mg2FeH6 as a heat storage material in comparison to MgH2 (Table 3) is its higher stability and hence a lower hydrogen dissociation pressure (Figure 8). So, for example, the dissociation pressure of Mg2FeH6 at 500 °C (66 bar) - is about 1/3 lower than that of MgH2 at the same temperature (100 bar). This gives for the construction of pressure containers for Mg2FeH6 an advantage versus containers for MgH2.


High temperature metal hydrides as heat storage materials for solar and related applications.

Felderhoff M, Bogdanović B - Int J Mol Sci (2009)

Crystal unit cell of Mg2FeH6; Mg-atoms are shown in blue, Fe-atoms are located in the centers of the octahedrons.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2662468&req=5

f7-ijms-10-00325: Crystal unit cell of Mg2FeH6; Mg-atoms are shown in blue, Fe-atoms are located in the centers of the octahedrons.
Mentions: As it can be seen in Figure 7, Mg2FeH6 is composed of Mg2+ cations and FeH64- anions in the form of octahedrons. In the center of the octahedrons is located a Fe atom, which is surrounded by six covalently bound H atoms. Alternatively to the high pressure method, Mg2FeH6 can be synthesized by reactive mechanical alloying of Fe and Mg elemental powders in a hydrogen atmosphere at room temperature [24–26]. The gravimetric hydrogen content of Mg2FeH6 is 5.5 wt.%. The volumetric hydrogen density reaches 150 kg m−3 which is double of the density of liquid hydrogen (70 kg m−3). The advantage of Mg2FeH6 as a heat storage material in comparison to MgH2 (Table 3) is its higher stability and hence a lower hydrogen dissociation pressure (Figure 8). So, for example, the dissociation pressure of Mg2FeH6 at 500 °C (66 bar) - is about 1/3 lower than that of MgH2 at the same temperature (100 bar). This gives for the construction of pressure containers for Mg2FeH6 an advantage versus containers for MgH2.

Bottom Line: High temperature metal hydrides offer high heat storage capacities around this temperature.Based on Mg-compounds, these hydrides are in principle low-cost materials with excellent cycling stability.Relevant properties of these hydrides and their possible applications as heat storage materials are described.

View Article: PubMed Central - PubMed

Affiliation: Max-Planck Institut für Kohlenforschung, Mülheim/Ruhr, Germany. felderhoff@mpi-muelheim.mpg.de <felderhoff@mpi-muelheim.mpg.de>

ABSTRACT
For the continuous production of electricity with solar heat power plants the storage of heat at a temperature level around 400 degrees C is essential. High temperature metal hydrides offer high heat storage capacities around this temperature. Based on Mg-compounds, these hydrides are in principle low-cost materials with excellent cycling stability. Relevant properties of these hydrides and their possible applications as heat storage materials are described.

Show MeSH
Related in: MedlinePlus