  Batteries vs. fuel cellsBy Brian Nadel(April 5, 2004) The traditional battery's days may be numbered. Thanks to recent advances in fuel-cell technology, your next laptop (or maybe the one after that) could run for days on a single charge. These next-generation batteries, which contain chemicals such as methanol stored in small tanks, certainly aren't your daddy's power source. More like tiny chemical plants, different types of fuel cells are currently used in space shuttles, experimental ecofriendly cars, and small power plants. NEC is developing a fuel cell for a laptop that could provide a mind-boggling 40 hours of battery life.
So how does a fuel cell work? "The fuel cell is based on the reverse principle of water electrolysis...[Fuel cells] work by having hydrogen and oxygen react to generate electricity," said Yoshimi Kubo, senior research manager overseeing NEC's project to create a fuel cell-powered notebook (see picture of prototype). Methanol, or methyl alcohol, is NEC's fuel of choice, and Kubo has created a prototype laptop that can run for five hours on about a pint of 10 percent fuel. When the tank is dry, forget about a power cord, because the fuel cell wants more methanol. Just pour in a small bottle of fuel, and it's ready to go. Rather than carrying a bagful of batteries on a long flight, all you'd need is a bottle of methanol, but be careful: methanol is a poison. For now, packaging is the biggest obstacle that fuel cells face. "Currently, the fuel cell cannot fit into a standard battery location," Kubo said. "It will need further development in order to fit into a notebook, and miniaturization is a challenge we're facing." If all goes well, by year-end NEC may have a 4.5-pound commercial notebook that runs for up to 40 hours on one tank of fuel. According to Kubo, NEC is attacking this problem from three directions: upping the concentration of methanol, using a low-power processor, and increasing the tank size. Fuel-cell-powered PDA By contrast, Hitachi is thinking smaller. Along with Tokai, a Japanese maker of cigarette lighters, Hitachi is working on a fuel cell-powered PDA. About the size of a AA battery, the fuel cell contains 2 ounces of 20 percent methanol fuel, and it powers a handheld computer for 6 to 8 hours. Before its planned launch next year, the companies will try to boost runtime by using 30 percent methanol fuel, making a 12-hour PDA a distinct possibility. All this adds up to big business over the next decade, according to Daniel Benjamin, a marketing analyst at Allied Business Intelligence, based in Oyster Bay, New York. "Fuel cells will provide a clean source of energy, but cost and technical issues will pose significant barriers." He has forecast the fuel-cell industry to be powering up with sales of only 5,000 units this year. But by 2011, there could be 200 million fuel cells of all sizes and capacities sold, powering everything from MP3 players to laptops. By then, we may be able to kiss our batteries good-bye, along with the eternal search for a power outlet to charge them--though finding fuel may create another problem.
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