Novel Metal Substrates for High Power Metal‐supported Solid Oxide Fuel Cells

Abstract

AbstractNovel high permeable porous Ni‐Mo substrates with different area densities of straight gas flow channels are successfully developed to improve the hydrogen fuel gas and the water byproduct diffusion in the anode and supporting substrate. Metal‐supported cell A, cell B and cell C with 5 × 5 cm2 supporting substrates are fabricated by atmospheric plasma spraying processes, these cells have the material structure of Ni‐Mo/LSCM (La0.75Sr0.25Cr0.5‐Mn0.5O3–δ)/NiO‐LDC(Ce0.55La0.45O2–δ)/SDC(Sm0.15Ce0.85O3–δ)/LSGM (La0.8Sr0.2Ga0.8Mg0.2O3–δ)/SSC(Sm0.5Sr0.5CoO3–δ). Cell A is supported by a conventional porous Ni‐Mo substrate without straight gas flow channels, cell B and cell C are supported respectively by the novel high permeable porous Ni‐Mo substrates with 1.5 and 2.73 channels per square centimeter. The power densities at 0.8 V and 750 °C are 550, 998 and 1,161 mW cm−2 for cell A, cell B and cell C respectively. The 100 h durability test at the constant current density of 400 mA cm−2 and 650 °C shows cell B and cell C have smaller degradation rates than cell A. The results obtained from AC impedance and circuit model analyses indicate that the electrolyte ohm and the cathode polarization resistances are significantly reduced by introducing straight gas flow channels into the supporting substrate.