Abstract: A solid oxide electrolyte material comprising an electrolyte material 50 using oxygen ions as carriers as a base material and a lithium-containing compound 60 added to the base material as a sintering additive is sintered at a sintering temperature of 1300° C. or lower to produce a solid oxide electrolyte 100. This solid oxide electrolyte material can reduce the sintering temperature to extend the range of choices of components of a solid oxide fuel cell and suppress reactions between other components to reduce the manufacturing cost. This solid oxide electrolyte material further can produce a solid oxide electrolyte with sufficient denseness and high gas tightness capable of suppressing fuel leak to improve the electromotive force and output.

Abstract: A shape and conductivity of a cylindrical porous metal substrate of low power collection losses are defined, and a solid oxide fuel cell of a high output or high start-up performance is provided by using the cylindrical porous metal substrate. In the solid oxide fuel cell of the invention, the cylindrical porous metal substrate which has a conductivity of 130 S/cm or more is used, and a power collecting section is connected to a position which does not exceed 100 cm from any place thereof. A first electrode, a solid electrolytic layer, and a second electrode are formed on a full periphery of the cylindrical porous metal substrate. Thus, it is possible to obtain a solid oxide fuel cell of easy cell formation and low power collection losses, i.e., high durability and a high output.

Abstract: Provided is a solid oxide fuel cell with long-term stability, small inside resistance and high power density which, at the same time, achieves to maintain excellent oxidation resistance, is capable of performing the process of fabricating the cell in the oxidation atmosphere at high temperatures at 1000° C. or more, and achieves reduction in the material cost. A porous metallic substrate is made of metal in which a coating containing aluminum is formed on the metal surface constituting the porous metallic substrate. Moreover, the porous metallic substrate is made of metal in which a coating, which contains aluminum and a high-conductive oxide generated by the phase reaction between elements contained in the metal constituting the substrate and elements contained in an oxidizer electrode, is formed on the metal surface constituting the porous metallic substrate.

Abstract: A fuel cell unit having an electrolytic layer with a catalyst layer and a gas diffusion layer arranged in the stated order on each principal surface is provided. The electrolytic layer is composed of a porous sheet and an electrolytic gel impregnated therein. The electrolytic gel is gel particles made of a proton conductive material. At least one of the catalyst layer and the gas diffusion layer has pores that are smaller than the electrolytic gel particles.

Abstract: A current collector includes a thin porous substrate and a hydrophilic material, where the hydrophilic material is provided to holes of the thin porous substrate or surfaces of skeleton elements of the porous substrate so that hydrophilic areas formed by the hydrophilic material successively pass through the thin porous substrate between both surfaces of the thin porous substrate. In the current collector, water is let out through the hydrophilic areas and does not stay on an interface between an electrode and the current collector so that reaction gas is not hampered and is supplied, unlike a conventional current collector. When the current collector is applied to a polymer electrolyte fuel cell, water is supplied with reliability through the hydrophilic areas to a polymer electrolyte membrane so that the polymer electrolyte membrane is effectively humidified.