CUSTOM MEMBRANE ELECTRODE ASSEMBLIES
The Membrane Electrode Assembly (MEA) is the core component of a fuel cell membrane electrode assembly and it helps facilitate the electrochemical reactions that are needed to separate and recombine protons and electrons. On the anode, fuel is decomposed into its components. From there, protons diffuse through the membrane while electrons follow the electrical pathway and do work. The electrons and protons recombine on the cathode in the presence of the oxidant to form water. Catalysts on each side enable reactions, while the membrane allows protons to pass through while keeping the gases separate and preventing an electrical short.
A typical MEA is composed of a Polymer Electrolyte Membrane (PEM), two catalyst layers, and two Gas Diffusion Layers (GDL). A MEA with this configuration is known as a 5-Layer MEA due to its composition. An alternative version of a membrane electrode assembly is the 3-Layer MEA which is composed of a polymer electrolyte membrane with catalyst layers applied to both sides, anode and cathode. An alternative name for this type of MEA is a Catalyst Coated Membrane (CCM). The diagram shows the difference in the types of MEAs.