By BARNABY J. FEDER

AMERICANS may have to wait 20 years, if not longer, for cars powered by fuel cells to become a familiar sight. But much smaller forms of fuel cell technology may well power electronic devices like laptop computers, video cameras and cellphones by the end of this decade.
Prototypes of long-lasting fuel cells that can replace batteries are being tested in laboratories in the United States and overseas. "Every big electronics company in the world is working on fuel cells in one way or another," said Jerry Hallmark, manager of Motorola's Energy Technology Lab in Phoenix. Some, like Intel, are going a step further and investing millions of dollars in start-up companies like PolyFuel and Neah Power Systems to accelerate development.
"There are some applications that are getting very close to commercialization," said Mike Lynn, head of a unit at the 3M Company that makes fuel cell components.
Mr. Lynn declined to be more specific, but many analysts expect fuel cells for consumer electronic devices to begin appearing next year in Japan. The betting is that the first to reach the market will be Toshiba, which is demonstrating a prototype of a methanol-powered cell this week at a trade show in Hanover, Germany. Toshiba says the cell could be sold next year with laptops.
Some 200 million to 500 million of the small cells, sometimes called microcells, might be sold annually by 2011, according to Allied Business Intelligence, a market research company in Oyster Bay, N.Y., that tracks new technology. Annual revenue to the fuel cell companies could be as much as $5 billion, said Atakan Ozbek, Allied's director of energy research.
But Mr. Ozbek and others said that despite the momentum of research and development, widespread microcell commercialization is not yet a sure thing.
"People underestimate the complexity of the system, and start-up companies have been cavalier about the availability of all the components they will need," said Dr. Brian M. Barnett, director of the electromechanical systems practice at Tiax, a technology consulting and development company based in Cambridge, Mass.
Like the fuel cells for cars promoted by President Bush and the even larger units being developed to provide electric power to factories and homes, most microcells generate electricity by chemically stripping hydrogen of its electrons. The electrons form a current running outside the cell while the positively charged ions left behind move through the cell. The ions and the electrons are recombined in a reaction with oxygen to form water, the only byproduct if pure hydrogen is used.
The basic concept for fuel cells was discovered in 1839, but researchers differ on the most practical way to design them to generate the most energy in the least space.
Fuel cells run most efficiently on pure hydrogen, but storing hydrogen compactly and safely is a huge hurdle. Many designers of large and small fuel cell systems are trying to get hydrogen from solid compounds that contain hydrogen or hydrocarbon fuels like methanol and ethanol, even though those fuels add other elements like carbon dioxide to the waste stream.

MICROCELLS have several economic advantages over their bigger cousins in the race to commercialization. Energy experts expect to cut the smaller cells' production costs to be competitive with those of batteries long before larger cells can be manufactured at anything close to the cost of internal combustion engines.
It should also be easier and less expensive to persuade retailers to sell fuel cells the size of battery packs than to transform the huge national infrastructure of gasoline stations.
But the biggest reason the smaller cells are expected to become popular sooner is their appeal as a convenience — something that consumers have shown a willingness to pay for — and not as an answer to energy and environmental problems.
Fuel cells that last far longer than do rechargeable batteries would free laptop computer users and television camera crews, for example, from the need to lug heavy and expensive backup battery packs. For similar reasons, the Defense Advanced Research Projects Agency and other military research groups have been investing in research on small fuel cells for more than a decade.
Fuel cells also offer the promise of "hot swapping," the ability to switch to a fresh power source without turning off a computer or phone. The user would simply add a new fuel cartridge to the cell before the reservoir ran dry.
"Half the interest in fuel cells is out of frustration with batteries," Dr. Barnett said.
Fuel cells for consumer electronics cannot come too soon for many product designers. Battery researchers have managed to double the capacity of lithium ion batteries in the last 10 years, making them the best-performing power source for mobile consumer electronic devices.
But sophisticated color displays, wireless access to the Internet, multiplayer games on cellphones and tablet computers for note-taking all demand more power than earlier generations of electronic devices. For these new products, consumers want power sources that last days or weeks instead of hours.
Batteries are likely to continue to improve slowly as researchers overcome drawbacks and develop new materials, like supercapacitors that store enough energy to allow the user of a hand-held device to quickly replace a dead battery without losing power. But the advantages of fuel cells will be hard to beat in the long run, according to energy experts.
Consider the number of hours that a kilogram of fuel can deliver a watt of power, one common benchmark in the portable-power industry. A kilogram of pure hydrogen can deliver one watt of power for 38,000 hours under ideal conditions. Methanol, a widely available fuel from which hydrogen is extracted in many fuel cells, delivers the watt for 6,000 hours. A fully charged lithium ion battery will do the job for just 150 hours.
Most consumer electronics products draw more than one watt of power. Laptops, for example, draw up to 20 watts, which is why batteries are often drained within a few hours. Travelers often need access to a recharging source (and plenty of time) or backup batteries, which can cost $100 or more for a laptop.
The cost of battery power for electronic devices is also high enough to entice businesses to invest in micro-cell development. Rechargeable-battery power costs roughly $3,000 for each kilowatt of power. By contrast, the fuel to power internal combustion engines costs roughly $50 a kilowatt. The fact that consumers already pay high prices for battery power is a central reason why many start-up fuel cell companies regard microcells as a quicker path to profits.

FOR all that, however, completing the last few steps to commercialization of microcells is still a big challenge. Some analysts wonder whether fuel cells might not turn out to be useful for only a few specialty applications.
"It's still an open question whether they will ever achieve practical value," said Dr. Jason Howard, head of the energy technologies team at Motorola's Energy Systems group.
The fuel cell's biggest shortcoming is that, unlike the battery, it cannot deliver large bursts of power, according to Dr. Howard.
Many fuel cell companies are coming around to the view of energy experts at potential customers like Motorola and Nokia that the first application for small cells may be as backups to batteries. Fuel cells could both recharge a cellphone and keep it working when a battery is drained. Alternatively, consumers could use the batteries only for spikes in power demand — when a laptop is turned on, for example, or when a cellphone call is placed — thus extending battery life.
In fact, using fuel cells with batteries makes enough sense that James D. Balcom, president and chief executive of PolyFuel, which is based in Palo Alto, Calif., expects almost all applications to be such hybrids. "Fuel cells and batteries were made for each other," Mr. Balcom said.
But even getting that far posestechnological problems because of the complexity of complete fuel cell systems. The basic hydrogen processing requires catalysts like platinum to speed up reactions and specialized membranes to separate the fuel. Then, there are tiny pumps and valves for moving air and liquids to where they are needed, components to collect and channel the electricity and methods for handling the reaction byproducts.
Typically, it takes a stack of fuel cells, rather than a single cell, to deliver the needed power. And so far, designers have been unable to make fuel cells operate as well as batteries across a range of temperature.
Other hurdles loom. Consumers are accustomed to looking for double-A, C or D batteries. But no comparable standards exist for the cartridges containing pure hydrogen, methanol or other fuel that users would pop into their fuel cell systems.
No one in the business expects widespread use of the cells until sizes are standardized, and no such efforts are under way.
Safety also remains an issue. The various fuels used are flammable, which is why they are prohibited on aircraft. PolyFuel has clearance from the Transportation Department for a prototype that dilutes the methanol in its cell by mixing it with water to be carried on aircraft, but other fuel cell designs have not yet been approved. PolyFuel itself would have to go back to federal regulators if it increased the percentage of methanol in its fuel cell design to improve performance.
The industry will also need to develop fuel cell cartridges that cannot be easily broken. Most analysts, though, expect fuel cells to be approved eventually for air travel.
In the meantime, some fuel cell designers are concentrating on niche markets that would not face regulatory tangles. MTI MicroFuel Cells, an Albany-based subsidiary of Mechanical Technology, recently signed an agreement to develop systems for Intermec, a leading supplier of mobile devices used to record inventory data in warehouses. And Jadoo Power Systems, based in Folsom, Calif., has delivered its first prototype fuel cell systems to a federal agency for use with video surveillance cameras; Jadoo declined to name the agency.
Jadoo expects to begin supplying similar systems, which are slightly larger than those used in consumer electronics, to local television news crews for use in video cameras later this year, according to Larry Bawden, the company's president and chief executive.

THIS is a market in desperate need of reliable, long-lasting power," said a senior executive at a company that supplies video crews to television stations. "It's a $50 million to $100 million market that's going to adopt it very rapidly if Jadoo can produce it," said the executive, who did not want to be identified because negotiations with Jadoo are in progress.
Selling to specific industries or the government also reduces the pressure to immediately develop ways to distribute fuel to consumers. In the long run, the major battery companies and companies like Bic, with long experience in distributing lighters, are the most likely candidates to bring the fuel cartridges to the consumer market.
A new realism about the final hurdles may be the best indicator that the cells really are moving closer to market. Mr. Ozbek of Allied Business said he has had to push his projection for when annual sales of microcells will hit 200 million units to 2011 — three years later than last year's projections.