ABSTRACT
Fuel cells directly produce power through the electrochemical reaction of a fuel and oxygen. A typical setup places the fuel and oxidizer streams on opposite sides of a semipermeable barrier (Figure 3.1). In the most popular type of fuel cell, Proton Exchange Membrane or Polymer Electrolyte Membrane (PEM) fuel cells, this barrier is, as the names imply, a polymer electrolyte that is permeable to protons (H+ atoms). It is, however, impermeable to electrons. This means that electrons are compelled to travel around the membrane through wires, creating an electrical current that can be utilized.
