Power Electronics

Waiting to Test-Drive the Next Hybrids

In the last five years, there has been much discussion about micro fuel cells and their potential as longer-running replacements for batteries in portable applications. Although the fuel cell papers being presented at conferences and the technology announcements being made by companies were all very interesting, I had to view them quite skeptically. Just about every technical presentation on micro fuel cells centered on the latest prototype development.

Naturally, there have been many unrealistic predictions about the pace of commercialization for micro fuel cells. Maybe the forecasts for these were marketing driven since most engineers are familiar with the corollary to Murphy's Law: Everything takes longer than expected. In fact, just a couple years ago, one marketing report predicted that nearly 9 million fuel cells would be sold for mobile phones in 2004. Did I miss something?

However, engineers should not be faulted for overzealous marketing. And none of what I have said so far should be construed as a knock against fuel cells. In the long run, after engineering challenges are solved, manufacturing and distribution are perfected, and any legislative barriers are hurdled, micro fuel cells may well replace batteries in many portable applications. I'm particularly upbeat about fuel cell prospects because of two announcements that were made this year.

In April, Neah Power Systems (Bothell, Wash.) described how it had demonstrated a multicell fuel cell stack using its silicon-based direct methanol fuel cell (DMFC) technology. Yes, this was another prototype announcement. But it also explained how, when completed, the silicon-based DMFC could replace the BA 5590 primary lithium battery that is now used extensively by the U.S. military. Neah Power Systems' roadmap called for completion of a working fuel cell system prototype by the end of this year, with qualification units shipping next year and commercially shipped units in 2007.

Then in August, UltraCell (Livermore, Calif.) announced a prototype portable fuel cell power source that used a novel micro reformer to run off of highly concentrated methanol. In tandem with this news, the company indicated it had received a contract to deliver a paperback-sized, 25-W fuel cell power system to the U.S. Army, which would be testing it in applications that may currently use the BA-5590. UltraCell plans to field test several hundred units in military applications next spring with production to follow in 2007.

I have no idea whether these two companies' timetables for getting micro fuel cells into production are realistic. But, I am encouraged that they both target environmentally demanding military applications. In the power electronics area, there is a strong history of taking technologies — like switching power supplies — that were previously developed in military applications and redeveloping them for commercial use.

The military will provide a testing ground in which performance will outweigh factors such as cost, product distribution, regulatory concerns and consumer perception — all of which play into the development of commercial products. And if the micro fuel cells can prove their worth on the battlefield, their prospects in the consumer arena could be bright. The fact that two radically different fuel cell designs are being tried seems to improve the likelihood of success.

Another encouraging factor is the way UltraCell positions its fuel cell as a run-time extender rather than a battery replacement. Although this concept is not new to micro fuel cells, the company has discussed this idea in terms of “hybridization” of the power sources for laptop computers. This term relates to intelligently managing power among multiple sources — ac adapter, fuel cell and battery — so that the end product is optimized both for run time and cost. As part of hybrid power systems, micro fuel cells could make their mark in consumer products. And given the strides now being made by hybrid electric vehicles, a hybrid in your laptop might seem like a natural choice if it becomes available to consumers.

TAGS: Mobile
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