Hydrogen storage materials, Any other practical materials?

The lack of practical hydrogen storage materials, even after great efforts by material scientist for many years, igives great influence on the commerical development of fuel cell today.

Hydrogen storage materials under development has still keeping fundamantal and basic research stages. Targeted governmental projects for storage materials such as Japanese NEDO's and US DOE's are reasonably high enough from practical application viewpoints. However, the present R&D status is far from the desired target values in that; (1) costs of raw materials have not been taken into account in that most materials to be synthesized might be too expensive for mass applications, (2) mass productivity of naterials practical uses have never been evaluated.  (3) temeprature levels at hydrogen release is too high for practical uses, (4) hydrogen capacity is evaluated only by material basis but not by the available hydrogen-content basis, (5) "reversible" nature for "on-board" application has not been proven experimentally, and (6) none of "reversible" material has been demonstrated yet in practical car applications.  

Sodium Borohydride (NaBH4) has been developed by MERIT since 2000 as the hydrogen storage material suitable for "off-board", "on-site" and "off-site" regeneration of "spent fuel" in fuel cell applications. MERIT believes Sodium Borohydride is the most practical and mass productive material for hydrogen storage.

MERIT has developed Sodium Borohydride as hydrogen fuel source in PEMFC and hydrogen carrier in a new fuel cell namaed Direct Borohydride Fuel Cell (DBFC). A new production and regeneration process has also been developed by MERIT that is based on the natural resource, Borax and Borate.

Hydrogen generation

What makes this method so special is that when Borohydride is hydrolyzed with water, it extracts as much hydrogen from water as it emits in the reaction. That means water is the resource to generate half of the hydrogen produced through this process.


The new fuel cell,  DBFC, has a theoretical voltage of either 1,64V. The reason that a high theoretical cell voltage can be obtained from this system is, that hydrogen exists as a negative ion (protide: H-) in the complex ion of BH4-. The fact which needs attention is that a protide can release twice as much electron as a proton. This difference leads to the difference of the theoretical voltage of an anode: -0,24V vs. -0,828V. Another advantage of the DBFC is that in comparison with other fuel cells the cross over phenomenon almost doesn't exist

Please refer to "Why BH4-?"section for more information about the advantages and the huge application area for Borohydride fuel.