Improvement in the Electrochemical Performance of Anode-supported Solid Oxide Fuel Cells by Meso- and Nanoscale Structural Modifications

To improve the electrochemical performance of anode-supported solid oxide fuel cells (SOFCs), microextrusion printing and wet infiltration techniques are employed for structural modification on the meso- (10-100 mu m) and nanoscale order, respectively. In the mesoscale structural modification, anode ridge structures are fabricated by extruding an anode slurry on the surface of a flat anode disk to extend the electrode-electrolyte interfacial area. In the nanoscale structural modification, gadolinium-doped ceria (GDC) nanoparticles are introduced into a porous lanthanum strontium cobalt ferrite (LSCF) cathode. To investigate the effects of mesoscale and nanoscale structural modifications, four different types of anode-supported SOFC including a conventional cell are prepared, and their performance is evaluated at several operating temperatures. It is found that both the mesoscale and nanoscale structural modifications reduce not only the polarization resistance but also the ohmic resistance in the cells, resulting in the improvement in cell performance. Moreover, it is clarified that the improvement in cell performance becomes greater with decreasing operating temperature. Specifically, the maximum power density in the cell where both mesoscale and nanoscale structural modifications are applied is increased by 66% at 600 degrees C and 34% at 700 degrees C, compared with that in the conventional cell.