Fuel Cell and Power Generating Method

• US 20080248338A1
• Filed: 09/29/2005
• Published: 10/09/2008
• Est. Priority Date: 10/05/2004
• Status: Abandoned Application

• Current Assignee: Aquafairy Corporation
• Original Assignee: Aquafairy Corporation
• Inventors: Yano, Masaya, Okeyui, Takuji, Sugimoto, Masakazu, Sugita, Taiichi
• Application Number:
  US11/576,677
• Publication Number:
  US 20080248338A1
• Time in Patent Office: Days
• US Class Current: 429/13
• CPC Class Codes: H01M 2008/1095 Fuel cells with polymeric electrolytes
• CPC Class Codes: H01M 8/026 characterised by grooves, e.g. their pitch or depth
• CPC Class Codes: H01M 8/0263 having meandering or serpentine paths
• CPC Class Codes: H01M 8/0271 Sealing or supporting means around electrodes, matrices or membranes
• CPC Class Codes: H01M 8/04089 of gaseous reactants
• CPC Class Codes: H01M 8/04104 Regulation of differential pressures
• CPC Class Codes: H01M 8/04231 Purging of the reactants
• CPC Class Codes: H01M 8/241 with solid or matrix-supported electrolytes
• CPC Class Codes: H01M 8/2457 with both reactants being gaseous or vaporised
• CPC Class Codes: H01M 8/2483 characterised by internal manifolds
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

A fuel cell having a unit cell formed of a sheet-like solid polymer electrolyte, its cathode-side electrode plate, an anode-side electrode plate, an oxygen-containing gas supply unit for supplying an oxygen-containing gas to the cathode-side electrode plate, and a hydrogen gas flow path unit for supplying a hydrogen gas to the anode-side electrode plate, regarding the unit cell which is to be a final stage of hydrogen gas supply, a flow path sectional area of the hydrogen gas flow path unit is not more than 1% of an area of the anode-side electrode plate and, at the same time, a discharge control mechanism for discharging a gas at 0.02 to 4% by volume relative to a hydrogen gas supplied to the unit cell is provided at an outlet of the hydrogen gas flow path unit.

Claims

1. A fuel cell comprising one or a plurality of unit cells formed of a sheet-like solid polymer electrolyte, a cathode-side electrode plate which is arranged on one side of the solid polymer electrolyte, an anode-side electrode plate which is arranged on the other side thereof, an oxygen-containing gas supply unit for supplying an oxygen-containing gas to the cathode-side electrode plate, and a hydrogen gas flow path unit for supplying a hydrogen gas to the anode-side electrode plate,

wherein, regarding the unit cell to be a final stage of a hydrogen gas supply, a flow path sectional area of the hydrogen gas flow path unit is not more than 1% of an area of the anode-side electrode plate, and a discharge control mechanism for discharging a gas at 0.02 to 4% by volume relative to a hydrogen gas supplied to the unit cell is provided at an outlet of the hydrogen gas flow path unit.

2. The fuel cell according to claim 1, wherein the discharge control mechanism is a pressure control valve which discharges a gas so that a primary side pressure becomes a constant pressure or lower.

13. The fuel cell according to claim 1, wherein the discharge control mechanism comprises a pressure control valve that can control a pressure in the internal surface side space at a prescribed value in a range of 0.02 to 0.20 MPa.

3. A fuel cell comprising a sheet-like solid polymer electrolyte, a cathode-side electrode plate which is arranged on one side of the solid polymer electrolyte, an anode-side electrode plate which is arranged on the other side thereof, a cathode-side metal plate which is arranged on a surface of the cathode-side electrode plate and allows for flow of a gas to an internal surface side, and an anode-side metal plate which is arranged on a surface of the anode-side electrode plate and allows for flow of a fuel to an internal surface side, characterized in that:

circumferences of the metal plates on both sides are sealed by bending pressing in the state where they are electrically insulated and, at the same time,

the anode-side metal plate has an inlet and an outlet for a fuel, and a pressure control valve which controls a pressure in an internal surface side space at a prescribed value is provided at the outlet.

4. The fuel cell according to claim 3, wherein the pressure control valve comprises a power imparting means for forcing a valving element towards a valve seat, a regulation mechanism for regulating a power imparting force of the power imparting means, a valve seat space having a valve seat and accommodating a valving element, an introduction flow path which is communicated with the valve seat space and can be sealed with the valve element, and a discharge flow path which is communicated with the outside from the valve seat space.

5. The fuel cell according to claim 3, wherein the pressure control valve can control a pressure in the internal surface side space at a prescribed value in a range of 0.02 to 0.20 MPa.

6. A power generating method of generating power by supplying a hydrogen gas and an oxygen-containing gas to one or a plurality of unit cells formed of a sheet-like solid polymer electrolyte, a cathode-side electrode plate which is arranged on one side of the solid polymer electrolyte, an anode-side electrode plate which is arranged on the other side thereof, an oxygen-containing gas supply unit which supplies an oxygen-containing gas to the cathode-side electrode plate, and a hydrogen gas flow path unit which supplies a hydrogen gas to the anode-side electrode plate,

wherein, regarding the unit cell to be a final stage of hydrogen gas supply, power generation is performed while an impurity gas is concentrated near an outlet by flow of a hydrogen gas, and a small amount of a gas is discharged from the unit cell so that an amount of a concentrated impurity gas becomes a constant amount or smaller.

7. The power generating method according to claim 6, wherein as the unit cell which is to be a final stage of hydrogen gas supply, a unit cell having a flow path sectional area of the hydrogen gas flow path unit which is not more than 1% of an area of the anode-side electrode plate is used and, at the same time, a gas is discharged from the unit cell at 0.02 to 4% by volume relative to a hydrogen gas supplied to the unit cell which is to be a final stage of hydrogen gas supply.

8. The power generating method according to claim 6, wherein a hydrogen gas is supplied to the unit cell which is to be a final stage of hydrogen gas supply so that a linear flow rate of a supply gas calculated based on a flow path sectional area of the hydrogen gas flow path unit becomes 0.1 m/second or more.

9. The power generating method according to claim 6, wherein a concentration of a hydrogen gas contained in a gas discharged from the unit cell is less than 50% by volume.

14. The power generating method according to claim 6, wherein said small amount of a gas is discharged from the unit cell when the pressure in the internal surface side space is a prescribed value in a range of 0.02 to 0.20 MPa.

10. A portable instrument fuel driving system comprising a fuel cell for supplying a hydrogen gas to an anode-side to perform power generation, a hydrogen gas generation means for supplying a hydrogen gas to the fuel cell with a hydrogen generator which generates a hydrogen gas by a reaction with a reaction solution, a reaction solution supply means for supplying a reaction solution to the hydrogen gas generation means, a supply side regulation mechanism for regulating a supply amount of a hydrogen gas to the fuel cell, and a discharge side control mechanism which is provided on an anode-side of the fuel cell and, when a primary side pressure is a constant pressure or higher, increases a discharge amount of a gas.

11. The portable instrument cell driving system according to claim 10, wherein the supply side regulation mechanism has a pressure control mechanism which controls a pressure of a hydrogen gas in a system so as to be in a set range.

12. The portable instrument cell driving system according to claim 10, wherein the reaction solution supply means has a reservoir which is communicated with the hydrogen gas generation means via a flow regulation unit, and a supply side regulation mechanism for regulating a generation amount of a hydrogen gas in the hydrogen gas generation means by regulating supply of a reaction solution from the reservoir with the flow regulation unit is constructed.