Characterization and Stack Testing of Solid Oxide Fuel Cells with Cathodes Prepared by Infiltration

Large footprint (144 cm(2)) cells with infiltrated (La0.6Sr0.4)(0.95)FeO3/yttria-stabilized zirconia (LSF-YSZ) cathodes were fabricated on a pre-production scale (approximately 90 cells/batch). The excellent electrochemical performance of the cells was confirmed both on single cell as well as on stack level. Changes in electrode properties were mapped out as a function of heat-treatment temperature. The microstructure of the porous zirconia backbone remained unchanged, but the surface area of the ferrite phase decreased gradually, as the electrode was treated to higher temperatures. Changes in surface area were accompanied by corresponding changes in pore size and total pore volume. In contrast to traditional composite electrodes, the in-plane conductivity of infiltrated LSF-YSZ cathodes decreased with increasing sintering temperature, a trend likely explained by microstructure alterations during the sintering of the non-random structure. (C) The Author(s) 2015. Published by ECS.