Ethanol fuel cells take aim at portables' power
By Charles J. Murray
EE Times
(07/13/01, 5:22 p.m. EST)
PARK RIDGE, Ill. — Fuel cells inched closer to the consumer electronics market this week as a portable fuel cell developer unveiled a technology that it claims could vastly improve the performance of handheld cell phones and notebook computers.
The technology, which drew mixed reactions from industry experts and competitors, reportedly could provide a shot in the arm for the ailing cell phone market by boosting the average "talking time" from about three hours to about 20 hours.
Medis Technologies Ltd. (New York), which introduced the new technology at this week's Fuel Cell 2001 Asian Conference in Tokyo, also said that its product could boost a notebook computer's time between recharges to approximately 12 to 15 hours.
"This could take wireless to the next step," said Bill Hyler, an analyst for CIBC World Markets (New York). "They look like they have the best technology in the portable fuel cell space right now."
Medis executives said that in addition to longer charge times, its new technology will also recharge in seconds and will cost less to use than conventional batteries. The company announced that it will make its fuel cells available to OEMs by the beginning of 2003 and expects them to replace cell phone and laptop batteries by 2004 to 2005.
"Ultimately, every cell phone and every laptop will use fuel cells," said Robert K. Lifton, chairman and chief executive officer of Medis. "It's obvious: No one will be able to compete in that market unless they have a fuel cell."
Lifton said the higher power and longer operating times of fuel cells will be necessary if mobile phone manufacturers expect to deliver new features, such as Internet capabilities and movies, to their products. Such features, he said, will draw more power but will be necessary if manufacturers expect consumers to buy new models.
"This is a product on which hundreds of billions of dollars, and perhaps even trillions of dollars, are dependent," Lifton said.
Industry experts were intrigued by the new technology, but questioned whether it would be cost-competitive. "They have a huge advantage in being able to charge up in a matter of seconds," said Donald Sadoway, a professor of material science and engineering at Massachusetts Institute of Technology and a nationally recognized battery expert. "They also have the ability to run for much longer periods of time than a conventional battery. But these are remarkable performance figures and I'm intrigued by their ability to manufacture these devices at low cost. I find that puzzling."
While experts acknowledged the technology's potential, most were cautious about seeing it as a successor to conventional battery schemes. "There's enough work being done that we know portable fuel cells will arrive and will find a niche in the marketplace," said Barry Huret, president of Huret Associates Inc. (Yardley, Pa.), a battery consultant. "But how big a niche, no one knows."
Simple, low-cost
Medis executives, however, said that the technology is deceptively simple and can be manufactured for low cost, making it a legitimate candidate for widespread use.
Unlike traditional fuel cell designs, which typically use hydrogen, Medis' new system employs direct conversion of ethanol to create electrical current. In that sense, it also departs from other techniques that use methanol as a fuel that is later converted to hydrogen before the reaction.
Medis said a proprietary additive provides the key to the fuel cell reaction. This so-called "X-additive," an electrolyte, is contained in a thumbnail-sized cartridge that also includes water and ethanol. The cartridge fits in the fuel cell, which is about the size of a cell phone battery.
Medis said the "X-additive" allows engineers to scrap proton exchange membranes, typically used in large hydrogen-based fuel cells. Proton exchange membranes, or PEMs, are considered too bulky and costly for the smallest fuel cell applications, and they can be damaged by high concentrations of methanol or ethanol. "Our people recognized that you can't make a small fuel cell with a PEM," Lifton said. "So they invented the proprietary liquid electrolyte."
The electrolyte enables ethanol or methanol to be converted directly to electricity, eliminating the need for hydrogen and PEMs. That allows higher concentrations of methanol or ethanol, up to 30 percent. The technique is so effective that company engineers were said to have effectively run the fuel cell on vodka.
Medis executives said the new technology offers energy densities "an order of magnitude higher" than anything available on the fuel cell market right now. The company said it has demonstrated energy densities of 150 W-hr/kg and expects that figure to climb to 450 W-hr/kg by the end of next year. In contrast, the lithium-ion batteries being used in today's cell phones have a theoretical energy density of 150 W-hr/kg, they said.
The announcement surprised some experts, many of whom expected direct ethanol conversion technology to be limited to smaller electronic devices, such as PDAs and cell phones, but not anything as large as a laptop computer.
Scaling up?
"Usually, you take a power performance hit when you use alcohols and methanols, but you gain the ability to package it in a tight space," said Bob Hockaday, chief fuel cell scientist for Manhattan Scientifics Inc. (Los Alamos, N.M.), a Medis competitor. "But if they can efficiently do this for smaller devices, then there's no reason they can't take it up to laptops and even larger systems, such as automobiles and power plants."
Medis is not expected to be alone in its effort to develop direct-conversion liquid fuel cells. Similar efforts are being undertaken by scientists at Los Alamos National Laboratory, Motorola Inc. and Manhattan Scientifics. Los Alamos and Motorola recently co-announced development of fuel-cell-on-a-chip technology, which they expect to see in devices like PDAs, cameras and electronic games.
But Medis is thought to be the first to propose OEM products and pricing. The company said it plans to manufacture its fuel cells for about $9 each and sell them to OEMs for about $15. The thumbnail-sized replacement cartridges, which could be popped into the fuel cell in seconds, would sell for about a dollar apiece.
The company's first ethanol-based product, scheduled for release late next year or in early 2003, will be a fuel-cell-based charger, which can be kept in a briefcase to recharge a conventional battery-based cellular phone. The system, which will offer 20 hours of recharge time before it needs cartridge replacement, is seen as a first step in bringing fuel cells to consumer products. Medis said the charger will eliminate the need for cell phone users to recharge by plugging their phone into a wall socket. Medis is working on the product with Sagem SA (Paris).
Medis is also working with General Dynamics Corp. on military applications for its ethanol-based fuel cell and said it has talked with cell phone makers as well. Ethanol is said to be an ideal fuel for mobile military communications systems because it is far less volatile than hydrogen. The Federal Aviation Administration also allows ethanol on commercial airplanes but forbids methanol.
Industry experts expressed skepticism, however, especially with regard to manufacturing costs and safety issues. Ethanol is flammable, they said, and could pose problems for cell phones left in hot locales. They suggested that years of additional testing would be required before such technologies could reach the market.
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