Metal Hydride Storage – Future
Technologies and New Advancements
Matthew Baxley
3 December 2012
NPRE 498
baxley2@illinois.edu
Overview of Metal Hydrides
-Potentially reversible storage medium for hydrogen
-Generally have good energy density, but specific
energy is less than conventional hydrocarbons
- A variety of different materials
-MgH2
-LaNi5H6
-NaAlH4
-Many others
Mechanism of Action
Mechanism of Action

2/nM + H2 <=> 2/nMHn +ΔH


Changing pressure and temperature will
cause the hydrogen to either be adsorbed or
desorbed
Under low temperature or high pressure the
hydrogen atoms can enter the gaps in the
parent metal, forming a solid solution
Goals for a Hydrogen Storage Medium in
Fuel Cell Vehicles
Note: Old targets (2003) were developed before widespread research into
fuel cell vehicles and therefore necessitated assumptions
Yang, Wolverton, and Siegel, 2009
Goals for a Hydrogen Storage Medium in
Fuel Cell Vehicles
Note: Old targets (2003) were developed before widespread research into
fuel cell vehicles and therefore necessitated assumptions
Yang, Wolverton, and Siegel, 2009
Capacity of Metal Hydrides to be used
in Fuel Cell Vehicles
Yang, Wolverton, and Siegel, 2009
Advances and Future Technologies

Proton Flow Battery

Metal Hydride-Carbon Compounds

Nanoconfinement of Light Metal Hydrides

Additional Uses
The “Proton Flow Battery”



Integrates a composite metal
hydride with a reversible proton
exchange membrane
Energy efficiency near that of a
lithium-ion battery, but provides
a hydrogen storage capacity of
about 0.6% H2 (significantly
more energy per unit mass).
Removes the need for an H2
gas intermediate
Andrews and Mohammadi (2014)
Metal Hydride-Carbon Compounds




Typical metal hydrides are a lattice of metal ions which form ionic
bonds with hydrogen
Complex metal hydrides contain additional compounds and cause
the hydrogen form covalent bonds with molecular anions containing
the hydride
Complex metal hydrides provide additional options for metal
hydride storage
 LiBH
4
 NaAlH
4
Excellent gravimetric storage capacity, but the kinetics of hydrogen
release are too slow for practical applications
Metal Hydride-Carbon Compounds


Study performed by Lin et al. explores
improving the complex hydride NaAlH4 with
Co/Carbon catalysts
This Co/Carbon mixture is an effective catalyst
for the dehydrogenation of metal hydrides.

Hydrogen spillover

Nano-confinement

Metal catalyzed hydrogen dissociation and
recombination
Nanoconfinement of Light Metal Hydrides



Jongh et al. investigate the
applications of nano-sizing and
scaffolding of light metal
hydrides
Reducing the size of light metal
hydride compounds to a
nanometer range allows for
much faster hydrogen
adsorption and desorption
This relatively speedy
reversibility is due to the
nanoconfining of the metal
hydride materials in a metalorganic scaffold
Additional Interesting Uses



Kim et al. - Metal hydride storage as a means
to power cell phones – 22 L battery
Reissner et al. - Development of metal
hydrides as a mean to power
telecommunications satellites during the
typical eclipse length of 72 minutes
Miura et al. - Hydrogen storage system using a
CO adsorbant to significantly reduce potential
incidental CO2 emissions from fuel cells
References




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Yang, J., Sudik, A., Wolverton, C., & Siegel, D. (2009). High capacity hydrogen storage materials: Attributes
for automotive applications and techniques for materials discovery. Chemical Society Reviews, 656-656.
Retrieved December 3, 2014, from http://wwwpersonal.umich.edu/~djsiege/Energy_Storage_Lab/Publications_files/CSR_H2_storage.pdf
http://www.pragma-industries.com/products/hydrogen-storage/
Andrews, J., & Mohammadi, S. (2014). Towards a ‘proton flow battery’: Investigation of a reversible PEM
fuel cell with integrated metal-hydride hydrogen storage. International Journal of Hydrogen Energy, 17401751. Retrieved December 1, 2014, from
http://www.sciencedirect.com/science/article/pii/S0360319913027341
Lin, S., Yang, J., Kung, H., & Kung, M. (2013). Hydrogen Storage Properties of Complex Metal HydrideCarbon Materials. Topics in Catalysis, 1937-1943. Retrieved December 1, 2014, from
http://link.springer.com/article/10.1007/s11244-013-0130-2#page-2
Liu, J., & Zhang, W. (n.d.). Improvement on Hydrogen Storage Properties of Complex Metal Hydride.
Retrieved from http://cdn.intechopen.com/pdfs-wm/38716.pdf
Jongh, P., Allendorf, M., Vajo, J., & Zlotea, C. (2013). Nanoconfined light metal hydrides for reversible
hydrogen storage. MRS Bulletin, 488-494. Retrieved December 1, 2014, from
http://onlinedigeditions.com/display_article.php?id=1422992