Fuel cell voltage response by controlling air flow on cathodes

Patent metadata

Field	Value
Publication number	US-2022320544-A1
Application number	US-202117217544-A
Country	US
Kind code	A1
Filing date	Mar 30, 2021
Priority date	Mar 30, 2021
Publication date	Oct 6, 2022
Grant date	—

Abstract

An automotive fuel cell stack includes anodes and cathodes, and a controller that, after receiving data indicating that load current demand is within a first pre-determined range, modulates a flow rate of air to the cathodes between zero and a pre-determined value until a cell output voltage achieves a value falling within a second pre-determined range greater than zero.

First claim

What is claimed is:

1 . A vehicle comprising:
a fuel cell stack arranged to generate power for propelling the vehicle; and a controller programmed to, upon activation of the vehicle,
pulse delivery of air to cathodes of the fuel cell stack such that a flow rate of air to the cathodes alternates between zero and a pre-determined value until a cell output voltage achieves a value falling within a pre-determined range, and
after the cell output voltage achieves the value falling within the pre-determined range, continually deliver air to the cathodes at a non-zero rate.

2 . The vehicle of claim 1 , wherein the controller is further programmed to begin delivering anode gas to anodes of the fuel cell stack before the pulse delivery.

3 . The vehicle of claim 2 , wherein the anode gas is hydrogen.

4 . The vehicle of claim 1 , wherein the pulse delivery of air to the cathodes continues until the controller receives a sensed input indicating an electrical current load demand exceeding the pre-determined range.

5 . The vehicle of claim 1 , wherein a ceiling value of the pre-determined range is 0.85 volts or less per cell.

6 . The vehicle of claim 1 , wherein the pre-determined value is a maximum value.

7 . The vehicle of claim 1 further comprising a pump or valve, wherein the pulse delivery of air to cathodes includes actuating the pump or valve.

8 . An automotive fuel cell stack comprising:
anodes and cathodes; and a controller programmed to, after receiving data indicating that load current demand is within a first pre-determined range, modulate a flow rate of air to the cathodes between zero and a pre-determined value until a cell output voltage achieves a value falling within a second pre-determined range greater than zero.

9 . The automotive fuel cell stack of claim 8 , wherein the pre-determined value is a maximum value.

10 . The automotive fuel cell stack of claim 8 further comprising at least one of a compressor, a blower, or a valve, wherein the modulating includes speeding up or slowing down the compressor or the blower or opening or closing the valve.

11 . The automotive fuel cell stack of claim 8 , wherein the first pre-determined range is indicative of a stop mode or a stop-start mode.

12 . The automotive fuel cell stack of claim 8 , wherein a ceiling value of the second pre-determined range is 0.3 volts or less per cell.

13 . The automotive fuel cell stack of claim 8 , wherein the modulating continues until the controller receives a sensed input indicating an electrical current load demand has exceeded the first pre-determined range.

14 . A method for a vehicle, having a fuel cell stack for power generation, comprising:
after deactivating the vehicle, modulating between zero and a pre-determined value a flow rate of air to cathodes of the fuel cell stack until cell output voltage of the fuel cell stack achieves a value falling within a pre-determined range.

15 . The method of claim 14 , wherein the pre-determined value is a maximum value.

16 . The method of claim 14 , wherein the modulating is achieved by speeding up or slowing down a compressor or a blower or opening or closing a valve.

17 . The method of claim 14 , wherein a ceiling value of the pre-determined range is 0.3 volts per cell.

18 . The method of claim 14 , wherein the modulating continues until the fuel cell stack is substantially free of anode gas.

Assignees

• Ford Global Tech Llc

Inventors

• Papasavva Stella
• Mejia Mejia Valentina
• Qiu Zeng

Classifications

• H01M8/04298

  Processes for controlling fuel cells or fuel cell systems · CPC title

• H01M8/04865 Primary

  Voltage · CPC title

• B60L58/31

  for starting of fuel cells · CPC title

• B60L50/72 Primary

  Constructional details of fuel cells specially adapted for electric vehicles · CPC title

• B60L50/75

  using propulsion power supplied by both fuel cells and batteries · CPC title