2007 R&D 100 Winner

In fuel cell assemblies, the flow field plates make up the bulk, by weight and volume, of the fuel cell stack, as well as being one of the most expensive components to manufacture. A research team at GrafTech International Ltd., Lakewood, Ohio, has addressed this situation with the creation of GRAFCELL Expanded Graphite Flow Field Plates. Their high corrosion resistance, good electrical and thermal properties, light weight, and low production costs make these flow field (bipolar) plates a key enabling technology for the commercialization of fuel cells.

Developed for polymer electrolyte membrane (PEM) fuel cells with applications in back-up power systems, stationary power, portable electronics, and automotive systems, the plates have significant advantages over competitive metal and graphite-filled polymer technologies. The GRAFCELL plates have an exceptional electrical conductivity and a high thermal conductivity. They also have the best overall balance of properties for flow field plate applications.Unlike metals, they’re not corroded by water or hydrogen, yet they can be made much thinner and possess superior electrical and thermal conductivities over graphite-filled polymers. The costs are also well within the Dept. of Energy targets of less than $2.00/plate by 2010 due to low materials costs and high-volume manufacturing.

Flow field plate technology

GrafTech International Ltd.

Originally published in R&D Magazine, September, 2007