Role of the reference position on overpotential measurements

Steady state polarisation measurements can be affected by electrode microstructure and geometrical arrangement. In particular, the relative position of the reference electrode with respect to the working and counter electrodes may influence the reference potential and therefore effect the overvoltage readings. The influence of the geometrical arrangement of the electrodes on the electrolyte potential lines, was simulated by solving the appropriate Maxwell equations. Simulations were in relatively good agreement with steady state polarisation and impedance spectroscopy results obtained with YSZ \ LaMnO3-based cells. The use of impedance spectroscopy to assess the appropriateness of a given electrode configuration is suggested.