Effects of non-planar interface and electrode parameters on the residual stress of solid oxide fuel cell

The thermomechanical response of solid oxide fuel cell will endanger its structural reliability. In this study, the effects of non-planar interface and electrode parameters are investigated by building a cosine anode-electrolyte interface with amplitudeAand wavelength lambda. Results show that the planar interface model cannot completely reflect the stress state of solid oxide fuel cells. Non-planar interface can stimulate high normal stressS(n)and shear stressS(t)at the interface, but these stresses are zero at the planar interface. Cosine interface causes approximately cosinoidalS(n)and sinusoidalS(t). The bigger the ratio of amplitude to wavelengthA/lambda is, the more serious theS(n)fluctuates. Electrode parameter analysis shows that increasing initial porosity of oxidized anode can reduce the maximumS(n)but increases the maximumS(t)and the cell deflection. Parameter study show that initial porosity between 0.15 and 0.25 is suitable. The effect of anode thickness on the maximumS(n)andS(t)is weak, while the electrolyte thickness has a relatively strong effect when the electrolyte thickness is less than 12 mu m. A NiO volume fraction between 0.52 to 0.58 is recommended to avoid overlargeS(n),S-t, and deflection.