Effects of Clamping Load on the Thermal Stress Distribution in a Planar SOFC with Compressive Sealing

Abstract

Finite element analysis (FEA) was conducted in this study to characterize the effects of clamping load on the thermal stress distribution in a planar solid oxide fuel cell (pSOFC) stack with compliant mica-based seal gaskets. Five different compressive loads (0.06, 0.1, 0.6, 1, and 6 MPa) were applied in the modeling to clamp the given pSOFC stack. Simulation results indicate that increasing the applied clamping load from 0.06 to 0.6 MPa could eliminate bending deformation in the positive electrode-electrolyte-negative electrode (PEN) assembly plate and its supporting frame. For a further increase of the applied clamping load to 1 and 6 MPa, the critical stresses in the glass-ceramic and mica sealants increased to a potential failure level. Thus, a 0.6-MPa clamping load is considered an optimal assembly load that can both eliminate bending deformation in the PEN-frame assembly plate and maintain acceptable critical stresses in the glass-ceramic and mica sealants.