To reduce the internal ohmic loss of the conducting electrolyte in a solid oxide fuel cell, it is fabricated as thin as possible, forcing designers to rely on either the anode or cathode as the structural supporting member. In order to supply oxygen efficiently to the electrode/electrolyte interface, the electrodes typically contain 30 - 50 vol. % open porosity. This high level of porosity significantly reduces the mechanical performance of the structure. In this study, the structure of electrodes has been modified using an underlying zirconia honeycomb laminated to the zirconia electrolyte. The structure increases the strength of the electrode structure and should allow for thinner electrodes, increasing gas transport to the electrolyte and reduced overpotential. Strengths of 70% and 82.5% open channel material were determined to be 250 MPa and 240 MPa, respectively. Honeycomb theory fails to predict failure stresses for ceramic materials; however, Object Oriented Finite Element (OOF) modeling identifies failure occurring at cell boundaries.
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