Abstract: A fuel cell system of the present invention includes: a fuel cell (10) having a fuel gas internal channel (11) and an oxidizing gas internal channel (12); oxidizing gas supplying passages (62) and (64); an oxidizing gas supplying device (31); oxidizing gas discharging passages (65) and (66) each having an upstream end communicated with the oxidizing gas internal channel (12) and a downstream end connected to the oxidizing gas supplying passage (64); a moisture exchanger (32) disposed on both the oxidizing gas supplying passage (62) and the oxidizing gas discharging passage (65); a gas circulating passage forming/canceling device (34) disposed on the oxidizing gas discharging passage (66); an air blower (35) configured to circulate a gas in a gas circulating passage; and an atmosphere communicating/closing device (33) disposed on the oxidizing gas supplying passage (62).

Abstract: A fuel cell system (100) is disclosed, which has a fuel gas generator (3) configured to be supplied with raw fuel, water and fuel for combustion to generate fuel gas by utilizing the combustion heat of the fuel for combustion; a fuel cell (1) configured such that the fuel gas is supplied to fuel gas routes (b1, 1a, c1) and oxidizing gas is supplied, thereby generating electric power; heating medium routes (b2, 1d, c2) configured such that the fuel gas is supplied thereto instead of being supplied to the fuel gas routes; a route switching device (4) configured to switch the destination of the fuel gas between the fuel gas routes and the heating medium routes; and a controller (8).

Abstract: To provide a polymer electrolyte fuel cell in which a reaction gas can be utilized efficiently for an electrode reaction even when a gap is formed between an anode-side sealing member and the end face of an anode and between a cathode-side sealing member and the end face of a cathode, and sufficient power generation performance can be ensured with a simple constitution. At least one of the anode-side sealing member and the cathode-side sealing member of the fuel cell includes an annular body, and at least one deformable protruding portion provided on the inner surface of the annular body.

Abstract: A fuel cell system includes a fuel cell that is subjected to a purge operation of supplying an inert gas to an anode and/or cathode upon shut-down of the fuel cell. The differential pressure ?P is defined as ?P=Pa?Pc where Pa is the pressure in an inlet-side flow path leading to the anode and Pc is the pressure in an inlet-side flow path leading to the cathode. The differential pressure during the purge operation is controlled such that the differential pressure during operation ?Po and the differential pressure during the purge operation ?Pp satisfy the relation: 0<?Po×?Pp. This makes it possible to reduce the stress exerted on a solid electrolyte membrane and improve the long-term reliability of the fuel cell.

Abstract: An operation method of a fuel cell system of the present invention has a water layer forming step in which before starting supply of at least one of the reducing agent and the oxidizing agent in a supply start operation of at least one of the reducing agent and the oxidizing agent, the water supplier supplies water to form a water layer so as to clog at least one of at least a portion of the reducing agent supply path which is located upstream of the reducing agent supply end in a flow direction of the reducing agent and at least a portion of the oxidizing agent supply path which is located upstream of the oxidizing agent supply end in a flow direction of the oxidizing agent.

Abstract: A fuel cell (101) of the present invention includes: a stack (1) formed such that one or more reacting portions (P) which generate electric power and heat by a reaction of a reactant gas and one or more heat transferring portions (H) which exchange heat with the reacting portions (P) by flow of a heat medium are arranged adjacent to each other in a stack direction of cells (2) by stacking the cells (2); a first heat medium supply manifold (8A) through which the heat medium is supplied to the heat transferring portions formed at both end portions (E) of the stack in the stack direction; a second heat medium supply manifold (8B) through which the heat medium is supplied to the heat transferring portions formed at a remaining portion (R) of the stack which portion is a portion other than the end portions of the stack; and a heat medium discharge manifold (9) through which the heat medium is discharged from the heat transferring portions.

Abstract: In a fuel cell system, during the state where the fuel cell system is not generating an electric power, a fuel gas passage and an oxidizing gas passage are closed, and an inert gas supply device (54, 58) supplies an inert gas to an anode space (111) which is substantially isolated from outside, the anode space including the closed fuel gas passage and a space connected to the closed fuel gas passage, while an air supply device (67, 70) supplies air to a cathode space (112) which is substantially isolated from outside, the cathode space including the closed oxidizing gas passage and a space connected to the closed oxidizing gas passage. With this, the fuel cell system is capable of achieving high energy efficiency and of surely preventing degradation of electrodes during the state where the fuel cell system is not generating the electric power, irrespective of repeated start-up and stop.

Abstract: A highly reliable polymer electrolyte fuel cell includes an anode-side separator plate and a cathode-side separator plate that are provided with an anode-side sealing member and a cathode-side sealing member, respectively. The anode-side and cathode-side sealing members seal the cell in cooperation with a polymer electrolyte membrane at sealing parts where the anode-side and cathode-side sealing members are opposed to each other, thereby preventing gas from leaking out of gas flow channels. One of the anode-side and cathode-side sealing members has a pointed rib that comes in contact with the sealing parts in a linear manner, and the other sealing member comes in contact with the sealing parts surface to surface.

Abstract: A fuel cell system includes a fuel cell that is subjected to a purge operation of supplying an inert gas to an anode and/or cathode upon shut-down of the fuel cell. The differential pressure ?P is defined as ?P=Pa?Pc where Pa is the pressure in an inlet-side flow path leading to the anode and Pc is the pressure in an inlet-side flow path leading to the cathode. The differential pressure during the purge operation is controlled such that the differential pressure during operation ?Po and the differential pressure during the purge operation ?Pp satisfy the relation: 0<?Po×?Pp. This makes it possible to reduce the stress exerted on a solid electrolyte membrane and improve the long-term reliability of the fuel cell.

Abstract: A separator plate for a polymer electrolyte fuel cell having excellent conductivity and moldability is provided. The separator plate is injection molded, using different compounds for molding the portion that requires conductivity and the portion that does not require conductivity. The separator plate comprises: an electronic conductor portion containing conductive carbon; and an insulating portion surrounding the electronic conductor portion. The electronic conductor portion has a first flow channel of a gas or cooling water on one side and has a second flow channel of a gas or cooling water on the other side.

Abstract: Problems of acceleration of drying of electrolyte membrane and local reaction, etc. can be properly coped with to attain the stabilization of performance of fuel cell.

Abstract: The deterioration of the catalyst can occur during prolonged storage, occasionally causing the deterioration of the durability of the fuel cell.

Abstract: In this vacuum heat insulator, an excellent heat insulating performance is obtained even at high temperature, and this excellent heat insulating performance is maintained for a long period. The hot insulating device and electric water heater using this vacuum heat insulator exhibit an excellent hot insulating performance, and are decreased in the power consumption for hot insulation. The vacuum heat insulator includes a laminate bag, and an insulating core placed in the laminate bag, and the inside of the laminate bag is evacuated in a vacuum state. The laminate bag is made of a laminate film. The laminate film includes a support layer, a deposition layer evaporated on the surface of the support layer, a protective layer placed at the surface side of the deposition layer, and a seal layer placed at the back side of the deposition layer. The deposition layer is formed of at least one material of metal and metal oxide.

Abstract: A fuel cell having high operation performance and reliability is provided by optimizing the shape and properties of a gas diffusion layer and the dimensions of a gas flow channel. The fuel cell evenly supplies a reaction gas to the catalyst of a catalyst layer and promptly discharges excessive water generated therein. The gas diffusion layer of the MEA comprises a first section having a surface A coming in direct contact with a separator plate and a second section having a surface B facing the gas flow channel of the separator plate. The porosity of the first section is lower than the porosity of the second section, and the second section protrudes into the gas flow channel, which has sufficient width and depth for the protrusion of the gas diffusion layer, and the width of a rib formed by the gas flow channel is sufficiently narrow.

Abstract: In this vacuum heat insulator, an excellent heat insulating performance is obtained even at high temperature, and this excellent heat insulating performance is maintained for a long period. The hot insulating device and electric water heater using this vacuum heat insulator exhibit an excellent hot insulating performance, and are decreased in the power consumption for hot insulation. The vacuum heat insulator includes a laminate bag, and an insulating core placed in the laminate bag, and the inside of the laminate bag is evacuated in a vacuum state. The laminate bag is made of a laminate film. The laminate film includes a support layer, a deposition layer evaporated on the surface of the support layer, a protective layer placed at the surface side of the deposition layer, and a seal layer placed at the back side of the deposition layer. The deposition layer is formed of at least one material of metal and metal oxide.

Abstract: A polymer electrolyte fuel cell including: a hydrogen ion conductive polymer electrolyte membrane; a pair of electrodes sandwiching the membrane; a pair of conductive separators each having a gas flow channel, one of which supplies a fuel gas to one of the electrodes and the other supplies an oxidant gas to the other electrode; and gaskets, each of which is sandwiched between the conductive separator and the hydrogen ion conductive polymer electrolyte membrane to surround the periphery of the electrode and the gas flow channel, wherein a gram of the conductive separator or the gasket, which is kept immersed in water of 80 to 100° C. for 50 hours, leaches into the water not more than 300 &mgr;g of TOC, not more than 50 &mgr;g of ammonium ion, not more than 50 &mgr;g of chloride ion, not more than 20 &mgr;g of bromide ion and not more than 10 &mgr;g of sulfurous acid ion.

Abstract: A highly reliable polymer electrolyte fuel cell includes an anode-side separator plate and a cathode-side separator plate that are provided with an anode-side sealing member and a cathode-side sealing member, respectively. The anode-side and cathode-side sealing members seal the cell in cooperation with a polymer electrolyte membrane at sealing parts where the anode-side and cathode-side sealing members are opposed to each other, thereby preventing gas from leaking out of gas flow channels. One of the anode-side and cathode-side sealing members has a pointed rib that comes in contact with the sealing parts in a linear manner, and the other sealing member comes in contact with the sealing parts surface to surface.

Abstract: A separator plate for a polymer electrolyte fuel cell having excellent conductivity and moldability is provided. The separator plate is injection molded, using different compounds for molding the portion that requires conductivity and the portion that does not require conductivity. The separator plate comprises: an electronic conductor portion containing conductive carbon; and an insulating portion surrounding the electronic conductor portion. The electronic conductor portion has a first flow channel of a gas or cooling water on one side and has a second flow channel of a gas or cooling water on the other side.

Abstract: A fuel cell having high operation performance and reliability is provided by optimizing the shape and properties of a gas diffusion layer and the dimensions of a gas flow channel. The fuel cell is capable of evenly supplying a reaction gas to the catalyst of a catalyst layer and promptly discharging excessive water generated therein. The gas diffusion layer of the MEA of this fuel cell comprises a first section having a surface A that comes in direct contact with a separator plate and a second section having a surface B that faces the gas flow channel of the separator plate. The porosity of the first section is lower than the porosity of the second section, and the second section protrudes into the gas flow channel. The gas flow channel has sufficient width and depth for the protrusion of the gas diffusion layer, and the width of a rib formed by the gas flow channel is sufficiently narrow.

Abstract: In this vacuum heat insulator, an excellent heat insulating performance is obtained even at high temperature, and this excellent heat insulating performance is maintained for a long period. The hot insulating device and electric water heater using this vacuum heat insulator exhibit an excellent hot insulating performance, and are decreased in the power consumption for hot insulation. The vacuum heat insulator includes a laminate bag, and an insulating core placed in the laminate bag, and the inside of the laminate bag is evacuated in a vacuum state. The laminate bag is made of a laminate film. The laminate film includes a support layer, a deposition layer evaporated on the surface of the support layer, a protective layer placed at the surface side of the deposition layer, and a seal layer placed at the back side of the deposition layer. The deposition layer is formed of at least one material of metal and metal oxide.