Thermal Stress Analysis of Solid Oxide Fuel Cell with Anode Functional Layer

In order to reduce the thermal stress of solid oxide fuel cell in the process of preparation and working, and improve the electrochemical performance of the cell, the functionally graded layer is introduced into the cell. Due to the property of the functionally gradient material changes continuously or stepwise in a certain direction, the layer can reduce the difference of material parameters and relieve the thermal mismatch stress between layers effectively. On the basis of the previous research and the idea of hierarchical method, the anode functional layer is introduced into the solid oxide fuel cell, and the material parameters of the sub-layers are controlled through the anode functional layer number and the nonlinear gradient component exponent n. Thermal stress of the solid oxide fuel cell is studied at 800 within the operating temperature. The results show that the maximum tensile stress of the anode layer and the maximum compressive stress of the electrolyte layer decreases by introducing the anode functional layer. With the same anode functional layer number, the maximum tensile stress increases with the exponent n, and the maximum compressive stress of the electrolyte layer decreases with the exponent n increase. The thermal stress may lead to cracks and destroy the solid oxide fuel cell structure. This research provides theoretical basis for design and optimization of the solid oxide fuel cell.