Computational Chemistry for Better Fuel Cells
Key Challenges: Rational development of polymer electrolyte membranes (PEMs). Fundamental scientific understanding of membrane morphology, water distribution, and proton transport is required to optimize conductivity, mechanical and chemical stability, durability upon prolonged operation at high temperature and low humidity, and low cost.
Why it matters: Fuel cells with polymer electrolyte membranes (PEMs) offer promise for efficient conversion of chemical energy to electrical energy for portable power and transportation applications. The membranes are key components of fuel cells. They conduct protons between the anode and cathode while separating the fuel and air reactants. Since no existing membrane exhibits an optimal combination of conductivity prolonged mechanical and chemical durability at high temperatures and low humidity, and low cost, extreme scale computing is helping in the rational design of these key devices
Accomplishments: The work was performed on a variety of NERSC systems and at EMSL. Researchers performed classical and quantum simulations of the common membrane “Nafion” as a function of hydration level. The studies showed how water percolation affects proton hopping across the membrane and quantified hydration level to achieve it. The results could lead to design of future polymer membrane materials that have lower uptake of water and yet offer faster proton transfer and transport.
Investigators: Ram Devanathan and Michel Dupuis, Pacific Northwest National Laboratory