Sorption kinetics is a critical issue in the development of hydrogen storage materials for transportation applications. Sandia researchers have studied the sorption kinetics of alanate at various temperatures and applied pressures and have decided a kinetics model^† that correlates absorption/desorption rates to applied hydrogen pressures, temperatures, and hydrogen concentrations in solid. The calculated results using this model fit well with experimental data.

The predictive capabilities of this empirical approach provide a useful modeling tool for optimizing the performance of the alanates over a range of hydrogen absorption temperatures and pressures. Under a typical hydrogen-loading situation (constant pressure), the optimum temperature for "fast fill" can be determined.

High hydrogen storage capacity is one of major challenges for on-board transportation applications. Until the recent discovery of alanate, hydrogen storage capacity did not increase much over past three decades. Sandia researchers are developing new materials with

Contact:
Weifang Luo
wluo@sandia.gov
(925) 294-3729

^† W. Luo and K. Gross, accepted for publication by the Journal of Alloys and Compounds.