Fabrication and Cell Properties of Flattened Tube Segmented-in-Series Solid Oxide Fuel Cell-Stack Using Decalcomania Paper

Abstract

In the segmented-in-series solid-oxide fuel cells (SIS-SOFCs), fabrication techniques which use decalcomania paper have many advantages, i.e., an increased active area of the electrode; better interfacial adhesion property between the anode, electrolyte and cathode; and improved layer thickness uniformity. In this work, a cell-stack was fabricated on porous ceramic flattened tube supports using decalcomania paper, which consists of an anode, electrolyte, and a cathode. The anode layer was <TEX>$40{\mu}m$</TEX> thick, and was porous. The electrolyte layers exhibited a uniform thickness of about <TEX>$20{\mu}m$</TEX> with a dense structure. Interfacial adhesion was improved due to the dense structure. The cathode layers was <TEX>$30{\mu}m$</TEX> thick with porous structure, good adhesion to the electrolyte. The ohmic resistance levels at 800, 750 and <TEX>$700^{\circ}C$</TEX> were measured, showing values of 1.49, 1.58 and <TEX>$1.65{\Omega}{\cdot}cm^2$</TEX>, respectively. The polarization resistances at 800, 750 and <TEX>$700^{\circ}C$</TEX> were measured to be 1.63, 2.61 and <TEX>$4.17cm^2$</TEX>, respectively. These lower resistance values originated from the excellent interfacial adhesion between the anode, electrolyte and cathode. In a two-cell-stack SOFC, open-circuit voltages(OCVs) of 1.915, 1.942 and 1.957 V and maximum power densities(MPD) of 289.9, 276.1 and <TEX>$220.4mW/cm^2$</TEX> were measured at 800, 750 and <TEX>$700^{\circ}C$</TEX>, respectively. The proposed fabrication technique using decalcomania paper was shown to be feasible for the easy fabrication of segmented-in-series flattened tube SOFCs.