Brendan Mahon, 2010, Mechanical and Aerospace Engineering
As Fuel Cells continue to be a source of interest and great potential in the search for more efficient, cleaner energy sources there is still a great deal to be learned and improved upon in their design. While there are many different kinds of fuel cells, each with their own inherent advantages and disadvantages, this research focused on Polymer Electrolyte Membrane Fuel Cells. A Polymer Electrolyte Membrane Fuel Cell takes Hydrogen and Oxygen as its two reactants and produces only water as a product. For this reason it is a source of great interest in the effort to reduce greenhouse gas emissions. Meanwhile, the Nafion membrane used in most Polymer Electrolyte Membrane Fuel Cells exhibits drastically different properties at different saturation levels. For this reason, it’s exceedingly important to study the properties of Nafion over the range of the fuel cell’s operating conditions and saturation levels. This research focused on diffusion rates of water in a Nafion fuel cell at varying pressures and temperatures and refining the methods used in their determination. While technical difficulties ultimately limited the extent of the study, additional studies should be conducted to determine how pre-stressing the membrane alters water diffusion rates along the direction of the stresses.