Potential and current distribution on the surface of a hydrogen gas diffusion anode

The current and potential distribution for a hydrogen gas-diffusion disc electrode with a relatively high ohmic resistance are investigated. A theoretical model for these distributions is presented. Potential differences between the edge of the electrode and points on the electrode surface have been measured for a hydrogen gas-diffusion electrode loaded with various total currents. From the results it is concluded that the proposed model is very useful to obtain the potential and the current density distribution along a hydrogen-gas diffusion disc electrode. Moreover, the allowable size of cylindrical holes in a perforated plate placed against the rear of the gas diffusion electrode for its current supply, can be calculated to achieve a reasonably uniform current distribution along the gas-diffusion electrode.