The application of infrared thermal imaging to the study of solid oxide fuel cells is demonstrated. The temperature increase accompanying polarisation of gadolinium doped ceria pellet cells is measured and the effect of temperature increase on polarisation characteristics is modelled. Temperature increases of the order of 2.5 degrees C were measured for heavily loaded pellet cells. Measurement accuracy of 0.1 degrees C and spatial resolution of 0.5 mm allow temperature distribution heterogeneity to be clearly discerned. A total heat transfer coefficient is derived from experimental results that allow the development of a model that predicts the extent of self-heating. For pellet fuel cells, self-heating is not expected to have a large effect on the polarisation characteristics; however, for thin electrolytes and high current density the effect becomes appreciable. (c) 2007 Elsevier B.V. All rights reserved.