Nancy Garland

U.S. DOE Progress Towards Developing Low-Cost, High Performance, Durable Polymer Electrolyte Membranes for Fuel Cell Applications.

Low cost, durable, and selective membranes with high ionic conductivity are a priority need for wide-spread adoption of polymer electrolyte membrane fuel cells (PEMFCs) and direct methanol fuel cells (DMFCs). Electrolyte membranes are a major cost component of PEMFC stacks at low production volumes. PEMFC membranes also impose limitations on fuel cell system operating conditions that add system complexity and cost. Reactant gas and fuel permeation through the membrane leads to decreased fuel cell performance, loss of efficiency, and reduced durability in both PEMFCs and DMFCs. To address these challenges, the U.S. Department of Energy (DOE) Fuel Cell Technologies Program, in the Office of Energy Efficiency and Renewable Energy, supports research and development aimed at improving ion exchange membranes for fuel cells. For PEMFCs, efforts are primarily focused on developing materials for higher temperature operation (up to 120 °C) in automotive applications. For DMFCs, efforts are focused on developing membranes with reduced methanol permeability. In this paper, the recently revised DOE membrane targets, strategies, and highlights of DOE-funded projects to develop new, inexpensive membranes that have good performance in hot and dry conditions (PEMFC) and that reduce methanol crossover (DMFC) will be discussed.

Research Strategies for Development of an Efficient and Effective Electrocatalyst for Polymer Electrolyte Membrane Fuel Cells and Progress Summary

The current electrocatalyst formulation for the polymer electrolyte membrane fuel cell (PEMFC), platinum supported on carbon (Pt/C), is known to be an effective promoter of redox reactions in fuel cells. However, the cost of Pt (currently ~

Scientific Aspects of Polymer Electrolyte Fuel Cell Durability and Degradation

2,000/troy ounce) hinders its use as a practical catalyst in commercial fuel cell-powered vehicles at current platinum loading. Another issue with respect to adoption of any electrocatalyst for vehicle applications is durability, especially in light of transportation drive cycle operation with start/stop, start-up/shut-down, and transient requirements. Thus, a robust alternative to current Pt/C technology is needed as the PEMFC electrocatalyst for the oxygen reduction reaction (ORR) on the cathode. The U.S. Department of Energy is funding cathode catalyst research on low-platinum group metal (PGM) catalysts, including alloys and core-shell systems, and on non-PGM catalysts. This paper provides an overview of the issues, approaches, and status of the research.