Onboard use of fuel cells, which will let notebook computers run three to 10 times longer without a recharge, has been questioned because they contain methanol, a flammable liquid.
But the DOT said that a cell designed by start-up PolyFuel can ride in airplane cabins when it emerges commercially because it contains a relatively low concentration of methanol, according to Jim Balcom, PolyFuel's CEO.
Fuel Cells are viewed as one of the likely "big"that will alter notebook architecture in the next few years. The replaceable, or refillable, fuel cartridges initially will be able to power laptops two to three times longer than standard laptop batteries, which now peter out at between two to four hours. Eventually, fuel cells will provide a charge 10 times longer than batteries, according to various sources.
Many analysts have viewed approval from transportation authorities as a necessary step to commercialization. If fuel cell powered notebooks can't be taken on planes, few people will buy them. It also helps psychologically.
"It is not surprising that people are hesitant, (but) once it gets approved, obviously it is viable," said Matt Sargent, notebook analyst at market research firm ARS. "There is a clear need for progress in the battery space. It has been one of the hard spots for the industry."
Air passengers, though, won't be stoking up alcohol-burning notebooks anytime soon. PolyFuel's cells remain in the development stage, and notebook makers won't likely put them in notebooks until late 2004.
"We've still got around a year and a half to go," said Balcom. "We're still in the technology development phase."
In PolyFuel's so-called eight molar methanol fuel cells, methanol, which ultimately provides the power, constitutes only 24 percent of the fluid. The rest is water.
The cells break down methanol molecules into protons, electrons and carbon dioxide. While the protons pass through a specialized membrane, the electrons can't and get shuffled into a wire that powers the device containing the cell. The by-products from the chemical reaction come together as water molecules.
Rather than completely forgo batteries, notebook makers will likely come out with computers that contain both batteries and fuel cells, said Balcom. Sanyo, among other Japanese manufacturers, has committed to coming out with fuel cell notebooks two or more years from now.
But other regulations could delay fuel cell notebooks from taking off. Airlines can independently ban certain products or devices from the cabin if they feel the objects could interfere with the handling of the aircraft, said a representative for the Federal Aviation Administration. The Department of Transportation could not be reached for comment.
Menlo Park, Calif.-based PolyFuel is a spinoff of research firm SRI Research. Investors include Intel and venture capital firm Mayfield Venture. Competitors include MTI MicroFuel Cells.