Electrochemical Characterization of Planar Anode Supported SOFC with Strontium-Doped Lanthanum Cobalt Oxide Cathodes

摘要

The electrochemical performance of anode supported cells with screen-printed strontium-doped lanthanum cobalt oxide cathodes was studied using electrochemical impedance spectroscopy and polarization measurements. In order to obtain information on the resistance contribution originating from the cathode alone, symmetrical cell measurements were carried out. Analysis of the symmetrical cell data by the distribution of relaxation times method, aided in the selection of an appropriate equivalent circuit for the cathode. Cell performance depends on the interdiffusion barrier layer and it is shown that the concentration polarization strongly overlap with the cathode losses, thus complicating the deconvolution of the impedance spectra into individual process and / or electrode specific contributions.