Hydrogen-storage properties and mechanisms of a novel Li-Al-N ternary system were systematically investigated by a series of performance evaluation and structural examinations. It is found that ca. 5.2 wt% of hydrogen is reversibly stored in a Li(3)N-AIN (1:1) system, and the hydrogenated product is composed of LiNH(2), LiH, and AlN. A stepwise reaction is ascertained for the dehydrogenation of the hydrogenated Li(3)N-AIN sample, and AIN is found reacting only in the second step to form the final product Li(3)AlN(2). The calculation of the reaction enthalpy change indicates that the two-step dehydrogenation reaction is more thermodynamically favorable than any one-step reaction. Further investigations exhibit that the presence of AIN in the LiNH(2)-2LiH system enhances the kinetics of its first-step dehydrogenation with a 10% reduction in the activation energy due likely to the higher diffusivity of lithium and hydrogen within AIN. (c) 2009 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.