The current status of solid state hydrogen storage technologies is that
none of the alternatives meets all of commercial criteria required for light
duty vehicle applications, nor are likely to in the near future. Major alternative
solid state storage technologies are based on the use of metal hydrides (more
specifically alanates), carbon nanomaterials, and metal organic framework
materials.
In general, major breakthroughs; not incremental improvements are needed
to meet technical goals for vehicle hydrogen storage systems. In this review,
we look at alternative hydrogen storage materials, volumetric and gravimetric
storage densities, current hydrogen storage systems weight and volume characteristics,
and storage system energetics; followed by a discussion of recent storage
materials advancements. Finally, a brief discussion of research needs is presented.
Recent advances in materials science, chemistry, physics, computation, and
nanoscience show considerable promise for realizing a breakthrough potential.
However, it is our opinion that despite 30 years historical progress, there
are still considerable technical and economic barriers that remain to be overcome.
Additional innovations and large amounts of both time and money will be required
in order to accomplish commercial goals. These efforts will require patience
and a high tolerance for incremental advancements, to provide further confidence
that a breakthrough is achievable.
