Published online by Cambridge University Press: 11 February 2011
Processing-induced residual stresses in the component layers of Solid Oxide Fuel Cells (SOFC's) can lead to fracture or to cell curvature which impedes stack assembly. Reducing or eliminating residual stresses to improve the mechanical behavior of the cells becomes increasingly important as the area of the cells is increased to increase the power of the fuel cell stack. Residual stresses in SOFC's result primarily from differential thermal expansion and sintering shrinkage between the component layers, such as the electrolyte and the anode support in a planar cell. This work investigates the impact of anode composition on each of these factors, with the ultimate goal of designing a flat, large-area cell. A range of anode compositions is investigated to determine the effect of different additives on the sintering behavior, and on the thermal and mechanical properties. Dilatometry, sintering shrinkage, scanning electron microscopy, and reduction studies are performed to correlate the microstructure, thermomechanical behavior, and composition. The experimental results are used to select an anode composition that leads to low overall cell curvature and improved mechanical behavior with respect to standard SOFC anode cermet materials.