Performance variation with SDC buffer layer thickness

The performance of anode-supported solid oxide fuel cells was investigated as the SDC buffer layer thickness was varied between ∼0.4 μm and ∼2.3 μm. The thickness of the buffer layer has a significant effect with the peak performance varying in magnitude by a factor of almost three. A peak power density of 1106 mW cm−2 was achieved at 800 °C and an optimal SDC buffer layer thickness of ∼1.5 μm. The performance variation was complex due to a balance between ohmic and polarization losses, triple phase boundary area, pin holes and interfacial reactions between the BSCF + SDC cathode, SDC buffer layer, and YSZ electrolyte. Understanding this variation is essential in order to compare two fuel cells having a different porous buffer layer thickness.