Method and Device for Enhancing Fuel Cell Lifetime

Patent metadata

Field	Value
Publication number	US-2016254556-A1
Application number	US-201415033621-A
Country	US
Kind code	A1
Filing date	Jan 24, 2014
Priority date	Oct 30, 2013
Publication date	Sep 1, 2016
Grant date	—

Abstract

A method for enhance lifetime of fuel cells via a device includes a step of creating a H 2 environment for a stack, wherein the H 2 environment is composed of H 2 confined within a gas-tight enclosure of the device. The device includes an enclosure-H 2 -inlet port, an enclosure-H 2 -outlet port, a stack-H 2 -inlet, a stack-H 2 -outlet, a stack-air-inlet, a stack-air-outlet, a stack-coolant-inlet, and a stack-coolant-outlet. The device prevents air from getting into the stack when the fuel cell system is in the idling or shutdown state. It solves the problems associated with the electrode damage caused by the open circuit voltage in the entire fuel cell non-operational time period and the electrode damage caused by the formation of an air/hydrogen boundary during either the startup or shutdown process. The device eliminates the damages of the open circuit voltage to either MEAs or stacks during their storage time period.

First claim

1 . A method to enhance lifetime of fuel cells comprising a step of: creating a H 2 environment for a stack of the fuel cell when the fuel cell is in an idling state or in a shutdown state before a next startup thereof, the H 2 environment is composed of H 2 confined within a gas-tight enclosure.

2 - 21 . (canceled)

22 . The method, as recited in claim 1 , wherein when the fuel cell is in the idling state or in the shutdown state, a stack-air-inlet, a stack-air-outlet, and a stack-H 2 -outlet of the stack are in a closed state, while a stack-H 2 -inlet of the stack is in an opened state.

23 . The method, as recited in claim 1 , wherein when the fuel cell is in the idling state or in the shutdown state, a stack-air-inlet, a stack-air-outlet, and a stack-H 2 -outlet of the stack are in a closed state, while a stack-H 2 -inlet of the stack is in the opened state for 10-20 minutes before it is closed.

24 . The method, as recited in claim 1 , wherein the H 2 environment has an absolute pressure larger than 1 atmosphere.

25 . The method, as recited in claim 1 , further comprising a step of: when the fuel cell is in the idling state or in the shutdown state, applying a dummy or auxiliary load to the stack to quickly consume O 2 remaining in a cathode chamber of the stack.

26 . The method, as recited in claim 1 , further comprising a step of: when the fuel cell is in the idling state or in the shutdown state, applying a flow of H 2 into to a cathode chamber of the stack to force out O 2 remaining in the cathode chamber of the stack.

27 . The method, as recited in claim 1 , further comprising a step of: when the fuel cell is in the idling state or in the shutdown state, applying an external power source to the stack to quickly consume O 2 remaining in a cathode chamber of the stack.

28 . A device for enhancing lifetime of at least a fuel cell, comprising:
a gas-tight enclosure, having a plurality of pipeline openings, for placing a stack of fuel cell therein; an enclosure-H 2 -inlet port and an enclosure-H 2 -outlet port provided at the gas-tight enclosure to allow communication between an interior of the gas-tight enclosure and an exterior thereof, wherein a H 2 environment is created within the interior of the gas-tight enclosure when the fuel cell is in an idling state or in a shutdown state before a next startup thereof; and a pipeline for extending through the pipeline openings of the gas-tight enclosure for connecting to the stack, wherein gaps between said pipeline and said pipeline openings are sealed, wherein the pipelines comprises a stack-H 2 -inlet, a stack-H 2 -outlet, a stack-air-inlet, a stack-air-outlet, a stack-coolant-inlet, and a stack-coolant-outlet for transporting fuel and coolant to the stack correspondingly.

29 . The device, as recited in claim 28 , further comprising a pressure regulator operatively coupled at the enclosure-H 2 -inlet at the exterior of the gas-tight enclosure.

30 . The device, as recited in claim 28 , further comprising two solenoid valves operatively coupled at the enclosure-H 2 -inlet port and the enclosure-H 2 -outlet port at the exterior of the gas-tight enclosure respectively.

31 . The device, as recited in claim 28 , further comprising a H 2 concentration sensor provided within the gas-tight enclosure.

32 . The device, as recited in claim 28 , further comprising a gas pressure sensor provided within the gas-tight enclosure.

33 . The device, as recited in claim 28 , wherein the gas-tight enclosure is made of material selected from a group consisting of stainless steel, aluminum or its alloys, and dense polyethylene.

34 . The device, as recited in claim 28 , wherein a thickness of the gas-tight enclosure is 1 to 3 mm.

35 . The device, as recited in claim 28 , further comprising an insulating material wrapping around at least an outer surface and an inner surface of the gas-tight enclosure.

36 . The device, as recited in claim 28 , further comprising a desiccant disposed within the gas-tight enclosure.

37 . The device, as recited in claim 28 , further comprising a plurality of covers for open-cathode stack, wherein a wider side of each of the covers cover at air channels of the stack and a narrower side of each of the covers sealed with a stack-air-inlet or a stack-air-outlet of the stack.

38 . The device, as recited in claim 28 , further comprising at least one operable and sealable door provided at the gas-tight enclosure.

39 . A method for storing MEAs and stacks by creating a H 2 environment for the MEAs and stacks during their storage, the H 2 environment is composed of H 2 confined within a gas-tight enclosure.

40 . A device for storing MEAs and stacks, comprising a gas-tight enclosure for placing the MEAs and the stacks therein;
an enclosure-H 2 -inlet port and an enclosure-H 2 -outlet port on the said enclosure, wherein a H 2 environment is created within the said enclosure; a pressure regulator operatively coupled at the enclosure-H 2 -inlet at an exterior of the gas-tight enclosure; and two solenoid valves operatively coupled at the enclosure-H 2 -inlet port and the enclosure-H 2 -outlet port at the exterior of the gas-tight enclosure respectively.

Assignees

• Zhang Yong
• Ma Wei
• Qi Zhigang

Inventors

• Zhang Yong
• Ma Wei
• Qi Zhigang

Classifications

• Y02E60/50

  Fuel cells · CPC title

• H01M8/04225 Primary

  during start-up · CPC title

• H01M8/241

  with solid or matrix-supported electrolytes · CPC title

• H01M8/04753

  of fuel cell reactants · CPC title

• H01M8/2457

  with both reactants being gaseous or vaporised · CPC title