What is a fuel cell?
A single fuel cell consists of an electrolyte sandwiched between two electrodes. Bipolar plates on either side of the cell help distribute gases and serve as current collectors.
Depending on the application, a fuel cell stack may contain a few to hundreds of individual fuel cells layered together. This "scalability" makes fuel cells ideal for a wide variety of applications, such as stationary power stations, portable devices, and transportation.
NREL's fuel cell research aims to lower the cost and improve the performance and durability of fuel cell technologies. Research is performed on a variety of fuel cell types—polymer electrolyte membrane (PEMFC), alkaline membrane (AMFC), and direct methanol fuel cells (DMFC)—which are generally differentiated by the fuel used.
NREL's fuel cell R&D, which is led by Bryan Pivovar, focuses on the following areas:
NREL's work in this area involves developing and optimizing advanced electrocatalysts and novel synthesis methods. Related projects concentrate on extended-surface catalysts with reduced precious-metal loading and improved performance, durability, and activity compared to standard catalytic materials. Researchers are investigating fuel cells and electrolyzer catalysts under acidic and alkaline conditions, with the goal of "thrifting" platinum, iridium, and their alloys (in acidic-based systems) and silver, cobalt, nickel, and their oxides/alloys (in alkaline-based systems).
Also under study are support materials for catalyst dispersion, with a focus on nitrogen-doped carbon supports and corrosion-resistant, non-carbon supports.
- Extended, Continuous Pt Nanostructures in Thick, Dispersed Electrodes. Bryan Pivovar. Annual Progress Report. (2013)
- Tungsten Oxide and Heteropoly Acid-Based Systems for Ultra-High Activity and Stability of Pt Catalysts in PEM Fuel Cell Cathodes. John Turner. Annual Progress Report. (2013)
- Novel Approach to Advanced Direct Methanol Fuel Cell Anode Catalysts. Huyen Dinh. Annual Merit Review and Peer Evaluation Report. (2011)
Alkaline membrane fuel cells enable the use of non-precious-metal catalysts, but they are vulnerable to ambient carbon dioxide conditions. This vulnerability decreases, however, at higher operating temperatures. NREL researchers are developing novel chemistries to enable higher-temperature and higher-current-density operation via the use of perfluorinated alkaline membranes.
Researchers are also exploring traditional proton exchange membranes with tethered heteropolyacid functionality to allow higher-temperature, lower-humidity operation and are investigating the stability of covalently tetherable cations.
- Advanced Ionomers and Membrane Electrode Assemblies for Alkaline Membrane Fuel Cells. Bryan Pivovar. Annual Progress Report. (2013)
- Hydroxide Conductors for Energy Conversion Devices. Bryan Pivovar. AMFC Workshop. (2011)
Electrode Design/High-Current-Density Operation
This cross-cutting research area focuses on incorporating novel catalysts into high-performance devices and investigating the impact of low-precious-metal loading on high-current-density performance.
NREL scientists are studying the effects of system-derived contaminants and hydrogen fuel quality on fuel cell performance and durability. Learn more about NREL's contaminants research and interactive material screening data tool, which helps fuel cell developers and material suppliers explore the results of fuel cell system contaminants studies.
- Effect of System Contaminants on PEMFC Performance and Durability. Huyen Dinh. Annual Progress Report. (2013)