Effects of anode and electrolyte microstructures on performance of solid oxide fuel cells

Abstract

To improve the performance of anode-supported solid oxide fuel cells (SOFCs), various types of single cells are manufactured using a thin-film electrolyte of Yttria stabilized zirconia (YSZ) and an anode functional layer composed of a NiO-YSZ nano-composite powder. Microstructural/electrochemical analyses are'conducted. Single-cell performances are highly dependent on electrolyte thickness, to the degree that the maximum power density increases from 0.74 to 1.12 W cm(-2) according to a decrease in electrolyte thickness from 10.5 to 6.5 mu m at 800 degrees C. The anode functional layer reduced the polarization resistance of a single cell from 1.07 to 0.48 Omega cm(2) at 800 degrees C. This is attributed to the provision by the anode layer of a highly reactive and uniform electrode microstructure. It is concluded that optimization of the thickness and homogeneity of component microstructure improves single-cell performances. (c) 2007 Elsevier B.V. All rights reserved.