As fuel cell technology continues to develop, engineers face a number of concerns when trying to specify materials for the components and housing materials of this technology.
ReliOn, a developer of modular, fault-tolerant, proton exchange membrane fuel cell technology, is currently developing a portfolio of stationary fuel cells for emergency and backup power requirements, uninterruptible power supplies, digital power needs, and a variety of off grid power requirements.
When developing the E-1100 hydrogen fuel cell – a 1,100 W fuel cell on a compact, rack-mountable package -- ReliOn consulted with Bayer MaterialScience LLC to choose the best material for many of the fuel cells proprietary components.
Kevin Dunay, market segment leader for electrical/electronic and information technology markets with Bayer MaterialScience, works in North America with his New Business and Sales team in the field, which work with the engineers that will be responsible for deciding on the materials utilized in fuel cell components.
Bayer MaterialScience likes to be engaged as early as possible in the design process as engineers try to define what the requirements are, giving the company time to consult their product portfolio and help the customer decide what may or may not be a fit for the customer’s product, says Dunay.
“We act as material consultants, really. If the application requirements aren’t a fit for us we’re going to tell them that,” says Dunay. “The more information we get up front, the better recommendations we can make for their product.”
While evaluating a material, designers and Bayer Material Science consider a number of different higher-level requirements:
- Mechanical -- How strong does the material need to be? Can it withstand impact? What is going to happen over the life of the product?
- Thermal -- What temperature range is the overall application going to be exposed to? Are any of the components going to be exposed to a different environment?
- Chemical -- What chemicals could the component be exposed to and is the chosen material compatible with it?
“A big topic now is sustainability,” adds Dunay. “What’s going to happen at the end of the product service life and what can be done with the components?”
ReliOn’s E-1100 hydrogen fuel cell uses a Bayer MaterialScience polycarbonate -- Makrolon 2458. The E-1100 hydrogen fuel cell has a modular, 7” and fault-tolerant design that can be used in a variety of telecommunications applications.
The material was a good fit for the fuel cell because it offers good dimensional stability over a wide range of temperatures and moistures, says Dunay. Other important features of this polycarbonate for fuel cell applications include long-term durability and the retention of mechanical properties over time.
The designers also need to take into consideration the flow characteristics of the material. Bayer MaterialScience supplies thermoplastics in raw material form, as pellets that can be injection molded into a shape selected by the OEM. Makrolon 2458 has a high flow, which makes it easy for the processor to mold and can help improve productivity, explains Dunay.
Bayer MaterialScience has also provided polycarbonate/acrylonitrile-butadiene-styrene (PC/ABS) blended materials for a different fuel cell – the XX25 reformed methanol micro-fuel cell from UltraCell Corporation of Livermore, CA.
The Bayblend resin offers high heat resistance, dimensional stability, high impact resistance, and resistance to a number of chemicals. It was used as part of the housing on UltraCell’s fuel cell. This was important, as the cell was designed to survive demanding environments like jungle, desert, and arctic conditions.