Development of ZrFeV alloys for hybrid hydrogen storage system

The combination of unstable hydrogen storage materials with a high pressure tank provides a potential solution to on-board hydrogen storage system for fuel cell vehicles. However, none of the available solid-state materials can fulfill all the requirements. In this work, ZrFeV-based alloys were systematically investigated for the possible use in such kind of hybrid storage devices. Among these alloys studied here, the composition (Zr_0.7Ti_0.3)_1.04Fe_1.8V_0.2 shows the best overall properties with a reversible hydrogen capacity of 1.51 wt, and a hydrogen desorption pressure of 11.2 atm at 0°C. Besides, this alloy also shows excellent stability without obvious capacity loss even after 200 hydrogen absorption/desorption cycles. Calculated results show that the gravimetric density of the hybrid storage system combining a 35 MPa high pressure tank with (Zr_0.7Ti_0.3)_1.04Fe_1.8V_0.2 alloy is 1.95 wt when the volumetric density reaches 40 kg/m<sup>3