Performance recovery of a fuel cell

Patent metadata

Field	Value
Publication number	US-9786934-B2
Application number	US-83138210-A
Country	US
Kind code	B2
Filing date	Jul 7, 2010
Priority date	Jul 8, 2009
Publication date	Oct 10, 2017
Grant date	Oct 10, 2017

Abstract

A method of improving the electrical performance of an operating fuel cell catalyst-containing cathode in a fuel cell connected to an electrical load by: reducing the flow of air to the cathode; disconnecting the load from the fuel cell; connecting a potentiostat to the fuel cell; cycling an applied voltage, current, or power to the fuel cell one or more times; disconnecting the potentiostat from the fuel cell; reconnecting the load to the fuel cell; and resuming the flow of air to the cathode.

First claim

What is claimed is:

1. A method of improving the electrical performance of an operating fuel cell catalyst-containing cathode in a fuel cell connected to an electrical load comprising:
stopping the flow of air to the cathode;
operating the fuel cell with the load connected to consume oxygen at the cathode, leaving humidified nitrogen at the cathode until the fuel cell produces a current below a current threshold and a voltage less than a voltage threshold;
disconnecting the load from the fuel cell;
connecting a potentiostat to the fuel cell;
cycling an applied voltage, current, or power to the fuel cell one or more times while the cathode is in contact with the humidified nitrogen;
disconnecting the potentiostat from the fuel cell;
reconnecting the load to the fuel cell; and
resuming the flow of air to the cathode.

2. The method of claim 1 , wherein the applied voltage ranges from a low of less than 0.1 V to a high of 1.5 V.

3. The method of claim 1 , wherein the applied voltage ranges from a low of less than 0.1 V to a high of 1.1 V.

4. The method of claim 1 , wherein the applied current has a current density that ranges from a low of less than −600 mA/cm 2 to a high of greater than +600mA/cm 2 .

5. The method of claim 1 , wherein the applied power has a power density that ranges from a low of less than −1 W/cm 2 to a high of greater than +1W/cm 2 .

6. The method of claim 1 , wherein the cycling is performed 1-20 times.

7. The method of claim 1 , wherein the cycling is performed 1-5 times.

8. The method of claim 1 , wherein the cycling is performed at 5-1500 mV/s.

9. The method of claim 1 , further comprising:
applying a voltage of less than 0.1 V to the fuel cell before disconnecting the potentiostat.

10. The method of claim 1 , wherein the current threshold is 5-15mA/cm2.

11. The method of claim 1 , wherein the voltage threshold is 0.05-0.15V.

12. The method of claim 1 , wherein the voltage threshold is 0.09 V.

Assignees

• Gould Benjamin D
• Lyons Karen Swider
• Baturina Olga A
• Us Navy

Inventors

• Gould Benjamin D
• Lyons Karen Swider
• Baturina Olga A

Classifications

• H01M8/04223

  during start-up or shut-down; Depolarisation or activation, e.g. purging; Means for short-circuiting defective fuel cells · CPC title

• H01M8/04925

  Power, energy, capacity or load · CPC title

• H01M2008/1095

  Fuel cells with polymeric electrolytes · CPC title

• H01M8/04895

  Current · CPC title

• H01M8/04865 Primary

  Voltage · CPC title