Reversible Li-storage in MgH2-based materials is studied by galvanostatic intermittent titration technology (GM), ex situ XRD and SEM. The breaking/recovering of Mg-H bond is proposed for the Li uptake/release at high voltage range (>0.1 V). Based on electrochemical testing, it is known that a charge capacity as large as 2217 mAh g(-1) can be delivered by MgH2-Mg material. Besides, the cycle calendar life of MgH2-based material can be improved by adding the ZrMn2 or LaNi5 as the mechanical robustness buffer. (C) 2008 Elsevier Ltd. All rights reserved.