According to one embodiment of the invention a fuel cell device array monolith comprises at least three planar electrolyte sheets having two sides. The electrolyte sheets are situated adjacent to one another. At least one of the electrolyte sheets is supporting a plurality of anodes situated on one side of the electrolyte sheet; and plurality of cathodes situated on the other side of the electrolyte sheet. The electrolyte sheets are arranged such that the electrolyte sheets with a plurality of cathodes and anodes is situated between the other electrolyte sheets. The at least three electrolyte sheets are joined together by sintered fit, with no metal frames or bipolar plates situated therebetween.