New Fluorinated Ionomers for Enhanced Oxygen Transport in Fuel Cell Cathodes

Cathodes in proton exchange membrane fuel cells (PEMFCs) that run on hydrogen are coated with a thin layer of conductive ionomer- The ionomer facilitates proton conduction to the costly platinum group metal (PGM) catalyst in the cathode, where oxygen reduction and reaction to form water occurs- Higher catalyst efficiency and lower catalyst loadings are desirable for industry PEMFC cost reductions- New ionomers with oxygen gas permeability higher than industry standard ionomers could improve PGM catalyst utilization at reduced loadings without sacrificing fuel cell performance- Compact Membrane Systems, Inc- has identified a family of ionomer materials which have very high oxygen permeability and are anticipated to have improved PEMFC performance compared to industry standards- The Phase I program will focus on synthesizing and characterizing varied compositions (equivalent weights) of these ionomer materials and formulation into ionomer dispersions- Thin membranes will be fabricated from the dispersions and their oxygen permeances will be measured against industry ionomer controls- Selected ionomers will be tested in membrane electrode assemblies (MEAs) against industry standard control MEAs- Improved cathode ionomers for PEMFCs could help accelerate their wide-spread adoption for a “greener” hydrogen energy economy where the US is no longer predominately dependent on fossil fuels- PEMFCs have higher efficiency than internal combustion engines and fuel cells can eliminate pollution such as CO2, a greenhouse gas caused by burning fossil fuels- If hydrogen is manufactured from the electrolysis of water, driven by renewable energy, then using PEMFCs eliminates greenhouse gases over the whole energy cycle- For PEMFCs the only by-product is water at the point of use-