Fuel cell R&D is far from easy street
By Charles J. Murray, EE Times
May 22, 2003 (10:02 a.m. EST)
URL: eetimes.com
When President George W. Bush called on the nation in January to rally behind the concept of hydrogen-powered cars, automakers and national labs began ratcheting up their efforts to put fuel-cell-powered vehicles on the road by 2010.
But while makers of automobiles-and, by extension, laptop computers and cell phones-may lick their chops at the thought of hydrogen-powered products, experts say the path to fuel cell nirvana could be a long and arduous one, requiring decades to achieve, in some cases.
University professors and researchers with no stake in the success or failure of the technology expect hydrogen-burning fuel cells to make minor inroads in consumer electronics in the next five years, but nary a dent in cars. For fuel cells to reach production automobiles by 2020, these sources said, scientists need a Nobel Prize-winning breakthrough to cut the cost of the technology by a hundredfold or more.
"As far as I know, no one who is technically literate is an enthusiastic supporter of fuel-cell-powered vehicles," said Donald R. Sadoway, professor of materials engineering and faculty fellow at the Massachusetts Institute of Technology, and a nationally recognized battery expert.
The assessment of unbiased researchers like Sadoway contrasts sharply with that of automakers, which have cranked up programs to develop the technology, and fuel cell suppliers, which are betting heavily on it. President Bush, too, is a profound believer, which is why he has called for funding of more than $1 billion to support fuel cell research over the next decade. To be sure, many scientists and engineers support the idea of further fuel cell research. But they warn against raising hopes too high, simply because they see no solutions on the horizon for the cost problems, particularly on the automotive side.
"At technical and scientific meetings, we're hearing nothing to lead us to the conclusion that there's been a big scientific breakthrough in fuel cells," said Elton Cairns, professor of chemical engineering at the University of California, Berkeley, and a developer of electric-vehicle batteries for General Motors during the 1970s.
"We need breakthroughs-in electrocatalysis and in polymer exchange membranes-if this vision is going to be realized," Cairns said.
Cost, cost, cost
Many researchers fear that hydrogen-powered vehicles will travel the path of the battery-powered vehicle a decade ago. Back then, some suppliers raised great expectations by claiming they could make batteries that would propel cars 400 miles between charges and which would recharge in just 15 minutes. When their research money was used up, however, the claims hadn't materialized. Automakers, meanwhile, have since all but abandoned battery-powered cars.
To avoid repeating that scenario, scientists say the public needs to be made aware that the shortcomings of fuel cells are knowledge-limited, rather than resource-limited. Merely throwing money and other resources at the problem won't guarantee a breakthrough, MIT's Sadoway said.
For example, Sadoway compared the automotive fuel cell dilemma to the search for a cancer cure, another knowledge-limited problem that has remained largely intractable. In contrast, other major scientific efforts, such as the U.S. program to put humans on the moon, were resource-limited. Once the money was there, the job could be done.
"When you have a knowledge-limited problem, there's no assurance you're going to solve it, no matter how hard you try," Sadoway said.
The key scientific obstacle facing fuel cell researchers is the fact that automotive fuel cells require large amounts of precious metals-usually platinum-and these are costly. "For fuel cells in automobiles, the issue is cost, cost, cost," said Cairns of UC Berkeley. "And maybe 'cost' a couple of more times."
Indeed, researchers say that fuel cell costs are currently hovering between $1,000 and $3,000 per kilowatt. To compete with vehicles equipped with internal combustion engines, those figures need to plummet to about $30/kW. "As long as you've got to buy your electrodes at the jewelry store, you can bet you're not going to put fuel cells on the road that are competitive with internal combustion engines," Sadoway said.
In products such as laptop computers and cell phones, such costs might be tolerated, scientists say. Laptop owners, for example, have traditionally been willing to pay $5,000/kW to $10,000/kW for batteries. Cell phones often employ batteries that run about $1,000/kW.
That's not to say fuel cells for laptops and cell phones are a slam-dunk, however. Challenges still loom regarding the use of hydrogen and methanol fuels in airports and on aircraft before such technologies can take off in the consumer electronics sector, experts said.
Unquestionably, the problems are much greater in the automotive arena, however. In addition to lower-cost electrode materials, scientists say that advances are needed for the creation of less costly polymer electrolyte membranes (which now run about $100/square foot) and bipolar plates, which are used between the cells in the fuel stack.
"It would take many grams of precious metals to make a fuel cell stack powerful enough to propel a car," Cairns said. "We're talking about a material demand that would put a strain on the precious-metals market."
Automakers, however, appear undaunted by the obstacles in their path. General Motors Corp. is making a major commitment to the technology, saying that fuel cells provide a design platform unlike anything yet seen in the 100-plus-year history of the automobile. GM is saying little about its technical plans, however. Asked about the need for technology breakthroughs, a spokeswoman said GM engineers know the technical path but declined to elaborate. "We don't want our competitors to know whether we've already achieved it or whether we are still working toward it," she said.
Researchers at Argonne National Lab's Transportation Technology R&D Center are developing on-board vehicle reformers to convert gasoline to hydrogen for use in automotive fuel cells.
The giant automaker plans to integrate fuel cells with by-wire technologies in a platform that would eliminate transmissions, steering columns, brake linkages, master cylinders and hydraulic fluid lines, enabling engineers to pack all functional components in an 11-inch-deep "skateboard" that would serve as a platform for a variety of vehicle bodies.
Similarly, Ford, DaimlerChrysler, Honda and Nissan are working with Ballard Power Systems Inc. (Vancouver, British Columbia) on fuel cell programs. Virtually all of the automakers are keeping mum on the precise details of their R&D.
By decade's end
General Motors reinforced its commitment to fuel cells early this month, when it announced that Dow Chemical Co. will use 500 of GM's fuel cells to produce up to 35 megawatts of stationary power at a Dow facility in Freeport, Texas. GM executives proclaimed that the goal of the deal was to "reduce the cost of fuel cells and improve their durability so that we may put them in cars by the end of the decade."
Some scientists see value in such efforts. "Car companies are realizing that fuel cells will benefit from the development of stationary applications," said Romesh Kumar, head of fuel cell development in the chemical-engineering department at Argonne National Laboratory. The lab's Transportation Technology Research and Development Center (Argonne, Ill.) is working on various aspects of fuel cell technology, including an on-board vehicle reformer that could convert gasoline to hydrogen for use in an automotive fuel cell power system. "Maybe-fuel cell-powered cars will come at the tail end of those stationary developments," he said.
Still, researchers and battery experts outside the automotive industry say they are baffled by carmakers' confidence in fuel cell technology, especially in light of the industry's battles over battery-powered cars. As recently as two years ago, automakers sued the state of California over a mandate forcing them to sell a designated percentage of "zero-emission" vehicles or face hefty fines. At the time, automotive engineers complained that some battery makers contributed to the problem by overstating the capabilities of their products.
Now, however, it's not the suppliers that are the source of all the optimism, they say. "The auto industry is not getting suckered," Cairns of UC Berkeley said. "They're suckering themselves."
Even Argonne's Kumar, who is a strong proponent of fuel cell research, warned against overoptimism. "People may be willing to pay for the perceived value of a fuel cell in their laptops," he said. "But in an automobile, they may not be."
Many researchers are concerned that the public will misunderstand fuel cell technology and underestimate the difficulties that lie ahead.
"People tend to look down their noses at this kind of technology," MIT's Sadoway said. "But it is every bit as elaborate as anything you'd find in high-energy physics or molecular biology. It's deceptively complex."
"The auto industry is building up public expectations for something that may not materialize," Cairns added. "This simply isn't going to happen unless we see some major breakthroughs." |
