Fuel cell system and control method for fuel cell system

Patent metadata

Field	Value
Publication number	US-10680264-B2
Application number	US-201816110840-A
Country	US
Kind code	B2
Filing date	Aug 23, 2018
Priority date	Aug 20, 2010
Publication date	Jun 9, 2020
Grant date	Jun 9, 2020

Abstract

A fuel cell system includes: a fuel cell stack; a fuel gas supply/exhaust unit; an oxidant gas supply/exhaust unit; and a control unit. The control unit determines whether there is a phenomenon in the fuel cell stack resulting from local power generation concentration within a plane of a membrane electrode assembly due to a water distribution. When it is determined that there is the phenomenon, the control unit controls at least one of the fuel gas supply/exhaust unit and the oxidant gas supply/exhaust unit.

First claim

What is claimed is:

1. A fuel cell system comprising:
a fuel cell having a membrane electrode assembly, the membrane electrode assembly having an anode and a cathode which are respectively bonded to both surfaces of an electrolyte membrane formed of a solid polymer;
a fuel gas flow passage flowing fuel gas along a surface of the anode;
an oxidant gas flow passage flowing oxidant gas along a surface of the cathode;
a fuel gas supply/exhaust unit configured to supply fuel gas to the anode and configured to exhaust anode off-gas exhausted from the anode, via the fuel gas flow passage;
an oxidant gas supply/exhaust unit configured to supply oxidant gas to the cathode and configured to exhaust cathode off-gas exhausted from the cathode, via the oxidant gas flow passage;
a power generation concentration determining unit programmed to:
receive data from a plurality of sensors, wherein the data indicates an operating condition of the fuel cell;
estimate, based on the operating condition, a water distribution, wherein the water distribution is a water distribution within a plane of the electrolyte membrane, a residual water distribution in the fuel gas flow passage and a residual water distribution in the oxidant gas flow passage;
determine whether a condition that indicates an amount of power generation per unit area exceeds an allowable value has occurred, wherein the power generation concentration determining unit determines the condition based on whether the water distribution exceeds a threshold value; and
determine, based on the water distribution, a cause of the condition, wherein the cause is an insufficient water content in the electrolyte membrane, an excessive amount of residual water in the fuel gas flow passage or an excessive amount of residual water in the oxidant gas flow passage;

and
a control unit programmed to:
control at least one of the fuel gas supply/exhaust unit and the oxidant gas supply unit based on the cause of the condition, and
control the fuel gas supply/exhaust unit so as to increase a flow rate of the fuel gas supplied to the anode when the cause of the condition is the insufficient water content in the electrolyte membrane.

2. The fuel cell system according to claim 1 , wherein when the cause of the condition is the insufficient water content in the electrolyte membrane, the control unit controls the oxidant gas supply/exhaust unit so as to reduce a flow rate of the oxidant gas supplied to the cathode.

3. The fuel cell system according to claim 1 , wherein when the cause of the condition is the insufficient water content in the electrolyte membrane, the control unit controls the oxidant gas supply/exhaust unit so as to increase a back pressure of the cathode off-gas.

4. The fuel cell system according to claim 1 , wherein when the cause of the condition is the excessive amount of residual water in the fuel gas flow passage, the control unit controls the fuel gas supply/exhaust unit so as to increase a flow rate of the fuel gas supplied to the anode.

5. The fuel cell system according to claim 1 , wherein when the cause of the condition is the excessive amount of residual water in the oxidant gas flow passage, the control unit is configured to controls the oxidant gas supply/exhaust unit so as to increase a flow rate of the oxidant gas supplied to the cathode.

6. The fuel cell system according to claim 1 , wherein when the cause of the condition is the excessive amount of residual water in the oxidant gas flow passage, the control unit controls the oxidant gas supply/exhaust unit so as to reduce a back pressure of the cathode off-gas.

Assignees

• Toyota Motor Co Ltd

Inventors

• Matsusue Masaaki

Classifications

• H01M8/0435

  of cathode exhausts · CPC title

• H01M8/1004

  characterised by membrane-electrode assemblies [MEA] (H01M8/12 takes precedence) · CPC title

• H01M8/04291 Primary

  Arrangements for managing water in solid electrolyte fuel cell systems (H01M8/04119 takes precedence) · CPC title

• H01M8/04992

  characterised by the implementation of mathematical or computational algorithms, e.g. feedback control loops, fuzzy logic, neural networks or artificial intelligence · CPC title

• H01M8/04753

  of fuel cell reactants · CPC title