That's where fuel cells come in. Unlike batteries, which are basically storage devices that hold a finite amount of fuel in an enclosed unit and expend it through combustion, fuel cells are energy generators that can expend high-density energy indefinitely as long as they're supplied with fuel, usually in the form of hydrogen and oxygen.
Power players
Companies such as Medis Technologies, Manhattan Scientifics, and Motorola Labs are well into the development of miniature fuel cells, finessing the technology into a reliable, powerful, and safe resource that could also influence product design changes. With fuel cells, there are no moving parts, and they're impervious to temperature change. That eliminates the need for fans--a significant issue when dealing with fast-performing transistors that become very hot.
The ultimate impact, of course, could be on mobile commerce. "Basic to the manufacturers' dreams is that you will buy a new cell phone or PDA and do what you do at home, in the office, or on the road," says Robert Lifton, chairman and CEO of Medis Technologies. "Sometime in 2003 or 2004, they have to offer you a totally mobile life and, to the extent they fall short of that, they may fall short of selling the product."
Analysts say we'll be seeing prototypes this year with product debuts hopefully in 2002, initially as battery adjuncts.








