%0 journal article
%@ 0360-3199
%A Lozano, G.A.,Bellosta von Colbe, J.M.,Klassen, T.,Dornheim, M.

%D 2014
%J International Journal of Hydrogen Energy
%N 33
%P 18952-18957 
%R doi:10.1016/j.ijhydene.2014.09.035
%T Transport phenomena versus intrinsic kinetics: Hydrogen sorption limiting sub-process in metal hydride beds
%U https://doi.org/10.1016/j.ijhydene.2014.09.035
33 
%X This paper discusses and compares the different sub-processes that occur during the hydrogen sorption of practical systems based on metal hydrides, i.e. intrinsic kinetics, heat transfer and hydrogen transport. Derived from their modeling equations, a resistance analysis is developed on these hydrogen sorption sub-processes for the first time. This analysis allows quantifying how strongly each sub-process affects the overall sorption kinetics in a hydride bed and thereby the sorption-rate limiting sub-process can be identified. It was found that in the case of the hydrogen absorption of sodium alanate material the heat transfer resistance is the dominant and rate limiting sub-process, with the exception of small geometries. Besides, the resistance due to hydrogen transport is negligible in comparison to the overall absorption resistance. As a consequence, simulations and designs of scaled-up systems based on sodium alanate material always require heat transfer optimization as one of the foremost considerations.