Acceptability envelope for metal hydride-based hydrogen storage systems

The design and evaluation of media-based hydrogen storage systems requires the use of detailed numerical models and experimental studies, with significant amount of time and monetary investment. Thus a scoping tool, referred to as the Acceptability Envelope, was developed to screen preliminary candidate media and storage vessel designs, identifying the range of chemical, physical and geometrical parameters for the coupled media and storage vessel system that allow it to meet performance targets. The model which underpins the analysis allows simplifying the storage system, thus resulting in one input-one output scheme, by grouping of selected quantities.Two cases have been analyzed and results are presented here. In the first application the DOE technical targets (Year 2010, Year 2015 and Ultimate) are used to determine the range of parameters required for the metal hydride media and storage vessel. In the second case the most promising metal hydrides available are compared, highlighting the potential of storage systems, utilizing them, to achieve 40% of the 2010 DOE technical target. Results show that systems based on Li–Mg media have the best potential to attain these performance targets.

► Steady state model of the storage bed set up to evaluate the acceptability envelope for metal hydrides.
► An easy and compact expression of the acceptability envelope developed.
► The model is applicable for different materials and under different operating conditions.
► Acceptability envelope model applied with the DOE technical targets as inputs.
► Acceptability envelope model used to compare different promising materials.