Apparatus and method for heating a fuel cell stack

Patent metadata

Field	Value
Publication number	US-10115979-B2
Application number	US-201414310794-A
Country	US
Kind code	B2
Filing date	Jun 20, 2014
Priority date	Mar 15, 2013
Publication date	Oct 30, 2018
Grant date	Oct 30, 2018

Abstract

An apparatus for heating a fuel cell stack in a cold start mode is provided. The apparatus comprises a fuel cell stack, a power converter, and a controller. The power converter may include a power switch and resistive heating element that is thermally coupled to the fuel cell stack. The controller is configured to activate the power converter, if a temperature is below a predetermined temperature value, to draw current from the fuel cell stack to cause the fuel cell stack to generate heat. Heat from the power converter is also applied to the fuel cell stack.

First claim

What is claimed is:

1. A vehicle comprising:
a fuel cell stack for powering the vehicle;
a power converter coupled to the stack, wherein the power converter includes a power switch and a resistive heating element;
a thermal system configured to transfer heat from the power converter to the fuel cell stack; and
a controller programmed to, in response to a stack temperature being less than a threshold, operate the fuel cell stack to generate a current which corresponds to a fuel cell voltage less than a normal vehicle operating voltage and operate the power converter to (i) generate a power converter output voltage at the normal vehicle operating voltage and (ii) draw the current from the fuel cell stack to increase heat generated within the fuel cell stack and to generate heat in the power converter to minimize a time to heat the fuel cell stack to the threshold, wherein the controller is further selectively programmed to bypass the resistive heating element and boost a fuel cell voltage to an operating voltage of a traction motor to enable the vehicle to drive away while heating the fuel cell stack.

2. The vehicle of claim 1 , wherein the resistive heating element is selectively engageable.

3. The vehicle of claim 1 , wherein operating the power converter includes modulating the power switch at a duty cycle greater than a max power duty cycle.

4. The vehicle of claim 1 , wherein operating the power converter includes modulating the power switch at a duty cycle within a range of duty cycles such that a further increase of the duty cycle results in a decrease in power output of the fuel cell stack to heat the fuel cell stack.

5. The vehicle of claim 1 , wherein the power converter is a boost converter, a buck converter, or a buck-boost converter.

6. The vehicle of claim 5 , wherein the power converter is a bi-directional converter.

Assignees

• Ford Global Tech Llc

Inventors

• Peterson Craig Winfield
• Hashim Hasdi R
• Degner Michael W
• Gillespey Brian

Classifications

• H01M2250/20

  Fuel cells in motive systems, e.g. vehicle, ship, plane · CPC title

• H01M8/04559

  of fuel cell stacks · CPC title

• H01M8/04268

  Heating of fuel cells during the start-up of the fuel cells · CPC title

• B60L11/1885

  Operations & Transport · mapped topic

• H01M8/0494

  of fuel cell stacks · CPC title