TiCrVMo alloys with high dissociation pressure for high-pressure MH tank

High-pressure metal hydride (MH) tank is a possible hydrogen storage system for fuel cell vehicles. The merit of the high-pressure MH tank system is improved by the use of a metal hydride with high dissociation pressure. In this study, TiCrV and TiCrVMo alloys with BCC structure has been developed for the high-pressure MH tank system. The developed TiCrVMo alloy shows 2.4 mass% of effective hydrogen capacity between 0.1 MPa and 33 MPa at 298 K, which has a dissociation pressure of 2.3 MPa at 298 K. By investigating the dissociation pressures of the synthesized metal hydrides, it is found that Mo has a special effect to increase dissociation pressure of the metal hydrides. This effect is probably attributed to the large bulk modulus of Mo compared to other elements.