Hydride ion conductors are the new frontier materials in the research field of solid-state ionics. Indeed, hydride ion conduction is particularly attractive for electrochemical devices such as fuel cells and batteries, because hydride ions have suitable ionic radii as mobile ions and strong reducing properties. Recently, our group reported for the first time pure hydride ion conductivity in new oxyhydrides. We propose therefore to study the elementary mechanism of hydride ion conduction in this promising class of materials, using quasi-elastic neutron scattering.