Solid electrolyte fuel cell and assembly

Abstract

An improved fuel cell assembly includes a plurality of series-connected fuel cells each including an electrically conductive separator, a compressed or sintered oxide powder cathode contacting the separator, a solid electrolyte contacting the cathode and a compressed or sintered powder anode contacting the electrolyte. Each of the separator, anode, electrolyte and cathode includes two internal holes each at least partially in registration with each other so that a fuel and an oxygen-containing gas may be admitted to separate tubes in the cell. Preferably, a gasket is disposed in the opening in the cathode receiving the fuel to shield the cathode from the fuel. A second gasket is disposed in the opening in the anode receiving the oxygen-containing gas to shield the anode from oxygen. Oxygen admitted to one of the tubes reaches the anode by first diffusing through the cathode and then being ionically conducted through the electrolyte to the anode. Oxygen at the anode reacts with the fuel, releasing heat. A peripheral barrier may partially protect the anode from oxygen. In an alternative embodiment, each of the elements of the cell includes only one hole, all of which may be aligned to form a single tube for admitting fuel. In that embodiment, oxygen diffuses from outside the cell, through pores in the cathode. In other embodiments, a single central fuel tube may have a plurality of oxygen supply tubes.