September 2004

Ant Power Packs

Continued from page 1

By Erika Jonietz

Only three years ago, industry watchers expected companies such as Samsung to sell methanol-powered cell phones by 2003. But problems with dynamic power demands, and with operating temperature and size, have stymied their development, and none has made it from lab to store.

Using formic acid as the fuel can solve all these problems, Masel says. For starters, although formic acid yields less electricity per molecule than methanol, it can deliver energy more rapidly than a comparable methanol fuel cell, getting around the dynamic-power issue. Formic-acid fuel cells also operate just fine at room temperature; to achieve the same level of power, methanol fuel cells must work at a scalding 60 °C and up -- impractical for a device used near the face. And methanol must be used in a diluted form in fuel cells; handling it requires tiny pumps and pipes that increase the devices' size. Formic acid doesn't face that problem, so Renew's fuel cells require no moving parts -- just a replaceable fuel cartridge.

A single cartridge should power a cell phone at least twice as long as the typical lithium-ion battery used today, Huff says. Some experts, however, are skeptical that formic acid will beat methanol into portable electronics. Two of the fuel's biggest problems are availability and toxicity, says Paul Kohl, director of the Georgia Tech Center for Innovative Fuel Cell and Battery Technologies. "Methanol is a more plentiful fuel than formic acid. You can buy it on the drugstore shelf," he says. "And I can wash my hands in methanol; I can't in formic acid," because the concentrated acid would burn his skin.

Predictably, Renew Power says it is well on its way to solving such problems. The real competition, Huff believes, is powerful, established lithium-ion batteries. But as cell phones grow more complex, the need for more power in a small space should eventually push the industry toward fuel cells. Being the first to have a fuel cell that fits inside a phone could put Renew Power at the head of the pack.