500W-Class Solid Oxide Fuel Cell (SOFC) Stack Operating with CH4 at 650oC Developed by Korea Institute of Science and Technology (KIST) and Ssangyong Materials

Abstract

We demonstrated a 500W-class SOFC stack employing anode-supported planar cells, stainless steel-based metallic interconnects, and glass-filler composite sealants for intermediate-temperature operation (~650oC). The stack was composed of 24 cells with the area of 10 x 10 cm2, and the single cells consisted of Ni - yttria-stabilized zirconia (YSZ) cermet anode, scandia-stabilized zirconia (ScSZ) electrolyte, gadolinia-doped ceria (GDC) interlayer, and Sr-doped lanthanum cobaltite (LSC) / GDC composite cathode. The stack exhibited the open circuit voltage close to the theoretical value at 650oC, which indicated the excellent sealing characteristics of the glass-filler composite system optimized for intermediate-temperature operation. It provided stable power output of over 500W with H2 and CH4 fuel at 650oC.