PEM fuel cell stack

A fuel cell stack having an anode side and a cathode side, the fuel cell stack comprising:

• two of an interface plate defining a first interface surface, a second interface surface, and a buss slot;
• two or more of an air plate defining a first air surface and a second surface opposite the first air surface, wherein one of the first air surface or second surface defines a plurality of air channels, and the other, opposite surface is flat;
• two or more of a reaction cell comprising a membrane electrode assembly disposed between a cathode seal and an anode seal;
• at least one of a fuel-air bipolar plate having a first fuel-air surface and second fuel-air surface opposite said first fuel-air surface,
• wherein one of the first or second fuel-air surface defines a plurality of air channels, and the other, opposite surface defines a plurality of fuel channels;
• and
• at least one of a fuel-coolant bipolar plate having a cooling surface defining a plurality of cooling channels and a fuel surface defining a plurality of fuel channels opposite the cooling surface,
• wherein the two of an interface plate, the two or more of an air plate, the two or more of a reaction cell, the at least one of a fuel-air bipolar plate, and the at least one of a fuel-coolant bipolar plate are arranged to provide a reaction cell to cooling surface ratio within the fuel cell stack of from 1:1 to 10:1;
• wherein the fuel cell stack includes:
• at least one of a repeating plate sequence having a reaction cell to cooling surface ratio of 2:1 and comprising:
• (a) the fuel-coolant bipolar plate,
• (b) one of the reaction cells,
• (c) the fuel-air bipolar plate,
• (d) an additional one of the reaction cells, and
• (e) one of the air plates;
• and
• at least one second plate sequence of a plurality of plates having a different reaction cell to cooling surface ratio than the reaction cell to cooling surface ratio of the repeating plate sequence;
• wherein the fuel cell stack includes one or more instances of the repeating plate sequence disposed within the fuel cell stack;
• wherein each cooling surface contributing to the reaction cell to cooling surface ratio is defined by a fuel-coolant bipolar plate disposed adjacent a flat surface of one of the air plates;
• and
• wherein the repeating plate sequence distributes cooling surfaces within the fuel cell stack relative to active reaction cells to manage temperature distribution across the fuel cell stack.