Thermal cycle characteristics of electrolyte and single cell in planar solid oxide fuel cell

Thermal cycle characteristics of electrolyte plate, positive electrode/elec trolyte/negative electrode(PEN), and single cell with alumina gas manifold in planar solid oxide fuel cell have been studied as a function of cooling and heating rates in the range of 2 to 8 degrees C/min. After thermal cycle test, no cracks in both electrolyte plate and PEN were observed in the who le range of heating and cooling rates. On the other hand, the single cell c aused cracking at the thermal cycle condition of 3 degrees C/min and above, which is due to difference in the thermal expansion coefficients between t he PEN plate and alumina gas manifold. Also, thermal cycle effect on single cell performance was examined. After thermal cycle, the cell performance a nd the open circuit voltage decreased considerably. These results were disc ussed as related to the electrochemical and material aspects of the electro des and electrolyte.