Abstract:

Fuel cells are the devices that convert chemical energy of a fuel directly into electrical energy by electrochemical methods without any intermediate mechanical steps. Among the existing fuel cells technologies, Solid Oxide Fuel Cell (SOFC) have been attracting great interest because of the advantages including high energy conversion efficiency, different fuel options, clean and quiet operation. The most important feature that distinguishes SOFC from other fuel cell and place it in a different category is the high operating temperatures (600-1000 °C). In addition, they do not depend on the limitation of the Carnot cycle thus their efficiency is higher than those of the internal combustion engines.  In this study, the problems of warpage and cracking which occur during the fabricating of an industrial size anode supported solid oxide fuel cell (SOFC) have been experimentally investigated and the fabrication parameters which enable to obtain anode supported SOFC with high strength has been determined. In the experimental study, the effects of composition, the powder size and the thickness of both anode support and anode functional layers on the shrinkage rate and warpage behavior have been studied. The shrinkage rates of these two layers have been modified such that they are close to that of a thin electrolyte layer via dilatometry tests and as a result the mechanical strength is improved by reducing the warpage behavior during sintering. The cells having 100 cm2 with the optimized fabrication parameters are manufactured and tested.

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