Study of contact resistance at the electrode–interconnect interfaces in planar type Solid Oxide Fuel Cells

Ohmic resistance at the interface of the electrode and the interconnect in Fuel Cells influences the overall performance of a cell. In the present work, contact resistances between interconnect and electrodes in planar type Solid Oxide Fuel Cells (SOFC) under various compression loads and at different temperatures are measured in laboratory scale experiments. The roughness of the electrode and interconnect surfaces is characterized and a mathematical model to determine the contact resistance at the interfaces with known morphology, is proposed. The experimental results are found to be in good agreement with the values obtained from the model.

► Theoretical and experimental study of contact resistance in SOFCs is carried out.
► Model capable of predicting contact resistance based on statistical surface parameters.
► A minimum load of 0.064 MPa is recommended for minimum contact resistance values.
► Contact resistance for cathodic/anodic interface is 33.3/48 mΩ cm2 at 0.064 MPa.
► Anodic/cathodic contact resistance increases/decreases with rise in temperature.