In this paper an experimental investigation on single planar solid oxide cells is presented. Tests were performed on SOFCs of anode-supported design at L.A.Q. IN.T.E.SE laboratory of Politecnico di Torino where a test facility was installed. In the paper results are presented concerning the characterization of planar circular-shaped cells from InDEC® with LSM and LSCF cathodes. The characterization was performed by taking V-I measurements over a range of temperatures between 650°C and 840°C with hydrogen as fuel, and air as oxidant. The dependence of the cell performance on the various polarization contributions was rationalized on the basis of a simple analytical model, through a parameter estimation on the experimental data. The apparent thermal activation energy E a has been evaluated from the temperature dependence of ASRs. The cell with LSCF cathode has a lower activation energy and thus it is suitable for operating temperature lower than ASC1 cell one. The fuel cell performance dependence on the temperature is due to the temperature dependence of ohmic and activation polarization. In particular, the performance limitation at low temperature is due to activation polarization for ASC1 and ohmic polarization for ASC2.

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