1. The hydrogen permeation ability of Ni-BaCe0.9Y0.1O3-δ (Ni-BCY) cermets with different Ni volume ratios were investigated from 600-750°C.
2. The highest hydrogen permeation rate was achieved with a Ni volume ratio of 30%.
3. For Ni-BCY(40/60) cermets, hydrogen permeation was controlled by bulk diffusion for thicknesses above 0.6mm, but was controlled by surface exchange for thicknesses of 0.36mm or less.