March 1, 2005

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VANCOUVER - Ballard Power Systems here last month reported what appears to be significant progress in three key areas - freeze start ability, durability and cost reduction - without reducing performance in its automotive fuel stack technology.

“We believe we are the first fuel cell developer to successfully demonstrate these key technology milestones simultaneously in a single fuel cell stack design,” said Charles Stone, Ballard’s vice president for research and development in a release. According to Stone, these demonstrations typically are done one requirement at a time, involving tradeoffs that don’t give a realistic picture of actual driving conditions when all three factors interact.

Ballard demonstrated its advances on a 10-cell demonstration stack. Together with more than 925,000 km (about 580,000 miles) of on-road experience, it shows Ballard is well on its way “to meeting our goals for a commercially viable fuel cell stack by 2010,” Stone was quoted in the release as saying.

The cost reduction, the simplest-to-explain aspect, was achieved to some extent by a 30% reduction of platinum catalyst loading, from about 1 mg/cm2 to about 0.7 mg/cm2. Normally, meeting all of these three criteria with less platinum is more difficult but Stone says Ballard’s researchers did exactly that without diminished performance. Ballard didn’t provide any per-kW cost figures.

Stacks Work at -20 Deg. C, Goal is -30 Deg.

In the freeze test, the stack demonstrated startup from minus 20 deg. C to power and shutdown in fifty cycles, with no degradation in performance or stack damage. Stone told H&FCL success was essentially due to careful analysis and manipulation of the entire system: systems conditions, managing the water in the stack, flowfield and manifold optimization, ice formation, freezing expansion, to mention just a few aspects.

The company’s goal is to achieve operability as low as minus 30 deg. C but, says Stone, minus 20 deg. C “is well within the operating requirements for most of North America and Europe.”

The objective was not to use any artificial aids such as heating devices or insulation, he said. “We defined a certain shutdown/startup protocol that would allow us to manage water in the stack compatible with the cell design to facilitate an efficient freeze start,” as he put it.

The stack was continuously tested through numerous drive cycles mimicking real dynamic driving conditions, he said. The stack recorded 2,200 hours of operation before a 5% reduction in performance was noted, but with no indication of membrane failure, usually a key failure mechanism in fuel cells, he said. DoE’s goal is 5,000 hours. “We found a way to decrease chemical degradation in the membrane, and we developed electrocatalysts for both the anode and cathode that are resistant to key failure mechanisms driven by automotive dynamic cycles,” he explained.

Contact: Ballard (media), Rebecca Young, 604/453-3804, rebecca.young@ballard.com.