Proton exchange membrane fuel cell with stepped channel bipolar plate
A fuel cell stack includes a membrane electrode assembly and a bipolar plate. The bipolar plate has a corrugated portion defined by an adjacent pair of proximal and distal peak portions and a sidewall segment connecting the peak portions. The sidewall segment and membrane electrode assembly at least partially define a flow channel. The sidewall segment includes a shoulder portion defining a step spaced away from the peak portions.
1. A vehicle comprising:
a fuel cell stack to power the vehicle and including
a membrane electrode assembly (MEA) and
a bipolar plate having
an adjacent pair of proximal and distal peak portions and
a sidewall connecting the peak portions, partially defining a flow channel with the MEA, and including shoulder segments formed with a relative angle therebetween in a range of 40 to 140 degrees to define a step spaced away from the peak portions.
2. The vehicle of claim 1 wherein the flow channel has a width and a depth greater than the width.
3. The vehicle of claim 1 wherein the bipolar plate has a generally uniform thickness.
4. The vehicle of claim 1 wherein a thickness of the bipolar plate is approximately 100 microns.
5. The vehicle of claim 1 wherein the bipolar plate is formed from metal.
6. The vehicle of claim 1 wherein the bipolar plate is formed from stainless steel foil.
7. The vehicle of claim 1 wherein the shoulder segments are formed with a relative angle therebetween in a range of 80 to 100 degrees.