Abstract: To provide a solid oxide fuel cell system capable of avoiding the reduction of air electrodes. The present invention is a solid oxide fuel cell system including: a fuel cell module, a fuel supply apparatus, a water supply apparatus, an oxidant gas supply apparatus, a reformer, and a control section for controlling the extraction of power, whereby the controller having a shutdown stop circuit for executing a shutdown stop when the fuel cell stack is above the predetermined temperature, and after a shutdown stop, during a period when pressure on the fuel electrode side is sufficiently higher than pressure on the air electrode side, and no reverse flow of oxidant gas to the fuel electrode side is occurring, a temperature drop operation is executed whereby high temperature oxidant gas remaining on the oxidant gas electrode side is discharged.

Abstract: Provided is a method for producing a solid oxide fuel cell comprising the following: a fuel gas flow path, a fuel electrode layer provided around the fuel gas flow path and containing an iron group element and a ceramic, a solid electrolyte layer provided around the fuel electrode layer, and an air electrode layer provided around the solid electrolyte layer. In a high-temperature state where the temperature of the solid oxide fuel cell, in which a fuel gas is supplied from one side of the fuel gas flow path and exhausted through an opening provided on the other side of the fuel gas flow path, is close to a power generation temperature, the solid oxide fuel cell is subjected to a process for regulating oxidation expansion rate of the fuel electrode layer, the oxidation expansion occurring when an oxidant gas flows in through the opening.

Abstract: To provide a solid oxide fuel cell system capable of avoiding the reduction of air electrodes. The present invention is a solid oxide fuel cell system including: a fuel cell module, a fuel supply apparatus, a water supply apparatus, an oxidant gas supply apparatus, a reformer, and a control section for controlling the extraction of power, whereby the controller having a shutdown stop circuit for executing a shutdown stop when the fuel cell stack is above the predetermined temperature, and after a shutdown stop, during a period when pressure on the fuel electrode side is sufficiently higher than pressure on the air electrode side, and no reverse flow of oxidant gas to the fuel electrode side is occurring, a temperature drop operation is executed whereby high temperature oxidant gas remaining on the oxidant gas electrode side is discharged.

Abstract: To provide a solid oxide fuel cell capable of executing a shutdown stop while sufficiently suppressing fuel cell oxidation. The present invention is a solid oxide fuel cell system having a fuel cell module, a fuel supply apparatus, a water supply apparatus, a generating air supply apparatus, a reformer, a fuel/exhaust gas passageway for guiding fuel/exhaust gas from a fuel supply apparatus through a reformer to outside; and a controller comprising a shutdown stop circuit; whereby the fuel/exhaust gas passageway functions as a mechanical pressure retention means, maintaining a pressure on the oxidant gas electrode side within the fuel cell module higher than atmospheric pressure, and maintaining a pressure on the fuel electrode side at a pressure higher than the pressure on the oxidant gas electrode side, until the fuel electrode temperature drops to a predetermined oxidation suppression temperature.

Abstract: To provide a solid oxide fuel cell system capable of avoiding the reduction of air electrodes. The present invention is a fuel cell system having: a fuel cell module, a fuel supply apparatus, a water supply apparatus, an air supply apparatus, a reformer, and a control section for controlling the extraction of power from a fuel cell module, whereby the controller includes a shutdown stop circuit for executing a shutdown stop when the fuel cell stack is above the oxidation suppression temperature, and after execution of a shutdown stop, during a period when pressure on the fuel electrode side is sufficiently higher than pressure on the air electrode side, and no reverse flow of air to the fuel electrode side is occurring, a temperature drop operation is executed whereby high temperature air remaining on the air electrode side is discharged.

Abstract: Problem: To suppress the occurrence of damage to fuel cell units caused by oxidation shrinkage of fuel electrodes. Solution Means: The invention is a solid oxide fuel cell for generating electricity by reacting hydrogen and oxidant gas in individual fuel cell units, wherein the individual fuel cell units comprise a fuel electrode, an oxidant gas electrode, and a solid electrolyte erected between fuel electrode and oxidant gas electrode; the fuel electrode comprises a composite material containing nickel, and the solid oxide fuel cell prevents shrinkage due to oxidation of the fuel electrode by maintaining the fuel electrode in an oxygen-free atmosphere until the temperature of the fuel electrode has dropped to 350° C. after electrical generation is stopped.

Abstract: Provided is a solid oxide fuel cell comprising the following: a fuel gas flow path, a fuel electrode layer provided around the fuel gas flow path and containing an iron group element and a ceramic, a solid electrolyte layer provided around the fuel electrode layer, and an air electrode layer provided around the solid electrolyte layer. In a high-temperature state where the temperature of the solid oxide fuel cell, in which a fuel gas is supplied from one side of the fuel gas flow path and exhausted through an opening provided on the other side of the fuel gas flow path, is close to a power generation temperature, the solid oxide fuel cell is subjected to a process for regulating oxidation expansion rate of the fuel electrode layer, the oxidation expansion occurring when an oxidant gas flows in through the opening.