Fuel cell system and fuel cell powered vehicle

Patent metadata

Field	Value
Publication number	US-9853311-B2
Application number	US-201314761810-A
Country	US
Kind code	B2
Filing date	Dec 9, 2013
Priority date	Jan 24, 2013
Publication date	Dec 26, 2017
Grant date	Dec 26, 2017

Abstract

A fuel cell system includes: an external load connected to a fuel cell; an electric power adjusting unit configured to adjust a generated electric power of the fuel cell in accordance with electric power consumption of the external load; a humidity control unit configured to control humidity of an electrolyte membrane in the fuel cell on the basis of the generated electric power of the fuel cell; an output voltage detecting unit configured to detect an output voltage of the fuel cell; and a cross leakage determining unit configured to cause the humidity control unit to increase the humidity of the electrolyte membrane when the fuel cell generates the electric power, the cross leakage determining unit being configured to determine whether a cross leakage amount increases or not on the basis of a change in the output voltage at that time.

First claim

The invention claimed is:

1. A fuel cell system adapted to generate an electric power by supplying an anode gas and a cathode gas to a fuel cell, the fuel cell system comprising:
an external load connected to the fuel cell;
a voltage sensor configured to detect an output voltage of the fuel cell; and
a controller programmed to:
adjust the generated electric power of the fuel cell in accordance with electric power consumption of the external load;
control humidity of an electrolyte membrane in the fuel cell on the basis of the generated electric power of the fuel cell;
increase the humidity of the electrolyte membrane when the fuel cell generates the electric power; and
determine whether a cross leakage amount increases or not on the basis of a voltage difference between an output voltage detected by the voltage sensor before the humidity of the electrolyte membrane is increased and an output voltage detected by the voltage sensor after the humidity of the electrolyte membrane is increased,

wherein the controller is programmed to start the determination in a case where the humidity of the electrolyte membrane is less than a predetermined threshold value.

2. The fuel cell system according to claim 1 ,
wherein the controller is programmed to increase the humidity of the electrolyte membrane so as to become larger than humidity controlled on the basis of the generated electric power of the fuel cell while controlling an output current of the fuel cell so as to be constant,
wherein the controller is programmed to determine that the cross leakage amount increases in a case where a change amount of the voltage difference is a predetermined value or more, and
wherein the controller is programmed to determine that a catalyst is deteriorated in a case where the voltage difference is less than the predetermined value.

3. The fuel cell system according to claim 1 ,
wherein the controller is programmed to increase the humidity of the electrolyte membrane by increasing an output current of the fuel cell,
wherein the controller is programmed to determine that the cross leakage amount increases in a case where the voltage difference is less than a predetermined value, and
wherein the controller is programmed to determine that a catalyst is deteriorated in a case where the voltage difference is the predetermined value or more.

4. A fuel cell powered vehicle on which the fuel cell system according to claim 1 is mounted.

5. A fuel cell system adapted to generate an electric power by supplying an anode gas and a cathode gas to a fuel cell, the fuel cell system comprising:
an external load connected to the fuel cell;
a voltage sensor configured to detect an output voltage of the fuel cell; and
a controller programmed to:
adjust the generated electric power of the fuel cell in accordance with electric power consumption of the external load;
control humidity of an electrolyte membrane in the fuel cell on the basis of the generated electric power of the fuel cell;
increase the humidity of the electrolyte membrane when the fuel cell generates the electric power;
determine whether a cross leakage amount increases or not on the basis of a voltage difference between an output voltage detected by the voltage sensor before the humidity of the electrolyte membrane is increased and an output voltage detected by the voltage sensor after the humidity of the electrolyte membrane is increased; and
determine whether the output voltage of the fuel cell drops or not on the basis of a reference voltage defined in advance in accordance with an output current of the fuel cell and the detected output voltage,

wherein the controller is programmed to start the determination whether a cross leakage amount increases or not in a case where the output voltage of the fuel cell drops.

6. The fuel cell system according to claim 5 ,
wherein the controller is programmed to increase the humidity of the electrolyte membrane by increasing an output current of the fuel cell,
wherein the controller is programmed to determine that the cross leakage amount increases in a case where the voltage difference is less than a predetermined value, and
wherein the controller is programmed to determine that a catalyst is deteriorated in a case where the voltage difference is the predetermined value or more.

7. A fuel cell powered vehicle on which the fuel cell system according to claim 5 is mounted.

8. The fuel cell system according to claim 5 ,
wherein the controller is programmed to increase the humidity of the electrolyte membrane so as to become larger than humidity controlled on the basis of the generated electric power of the fuel cell while controlling an output current of the fuel cell so as to be constant,
wherein the controller is programmed to determine that the cross leakage amount increases in a case where the voltage difference is a predetermined value or more, and
wherein the controller is programmed to determine that a catalyst is deteriorated in a case where the voltage difference is less than the predetermined value.

Assignees

• Nissan Motor

Inventors

• Okui Takehiko

Classifications

• H01M8/04664

  Failure or abnormal function · CPC title

• H01M2008/1095

  Fuel cells with polymeric electrolytes · CPC title

• H01M8/04291 Primary

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

• B60L3/0069

  relating to the isolation, e.g. ground fault or leak current · CPC title

• H01M8/04925

  Power, energy, capacity or load · CPC title