Composite fuel cell bipolar plate

A device comprising:

• a battery configured to store electricity;
• and
• a fuel cell electrically connected to the battery, wherein the fuel cell comprises:
• a first membrane electrode assembly (MEA) and a second membrane electrode assembly (MEA), wherein each MEA has an anode side and a cathode side;
• a bipolar composite plate assembly located between the anode side of the first MEA and the cathode side of the second MEA, the bipolar composite plate assembly comprising:
• a first composite sub-plate comprising:
• first lands located against the anode side of the first MEA;
• first protrusions located at a distance from the anode side of the first MEA;
• and
• first ribs interconnecting the first lands and first protrusions;
• and
• a second composite sub-plate comprising:
• second lands located against the first lands;
• second protrusions located against the cathode side of the second MEA;
• and
• second ribs interconnecting the second lands and second protrusions;
• wherein:
• each composite sub-plate has a web thickness of from 0.1 mm to 0.4 mm;
• the first composite sub-plate and the second composite sub-plate are nested together to form coolant flow channels between the first lands and the second protrusions;
• first flow channels open to the anode side of the first MEA are defined between the first MEA and the first protrusions;
• second flow channels open to the cathode side of the second MEA are defined between the second MEA and the second lands;
• and
• the first composite sub-plate has a first repeating pattern of first lands, first protrusions, and first ribs;
• the first repeating pattern has a first period;
• the second composite sub-plate has a second repeating pattern of second lands, second protrusions, and second ribs;
• the second repeating pattern has a second period;
• and
• the second period is equal to half of the first period.