Hydrogen absorption in a Ti-6Al-4V alloy prepared by ball milling was investigated in view of the reversible storage of hydrogen in a solid state. The material characterization by X-ray and neutron diffractometry demonstrated the formation of a single a phase whose unit cell expanded during the hydrogen absorption. The maximum storage capacity of this alpha phase was 1.8 wt% H and no hydride formation was observed, The existence of such a particular supersaturated hexagonal phase was attributed to the strongly defective structure formed by the mechanical alloying process. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.