Batteries of the Future

Imagine you've been chatting for hours on your cellphone and it's running low on power. But instead of looking for the nearest electrical outlet, you recharge the phone with a squirt of clear liquid from a little bottle.

That's the vision of Toshiba Corp. and a number of other Japanese electronics companies, which are readying gadgets that will swap their batteries for a long-anticipated alternative energy source: fuel cells. Fuel cells combine hydrogen with oxygen to produce electricity, providing power in a way that is potentially cleaner and cheaper than many conventional energy sources.

Long-running interest in fuel-cell technologies has accelerated recently amid soaring oil prices. Ultimately, the hope is that fuel cells will be able to power cars or electric generators for homes. But the technology has been tricky to develop and extremely difficult to commercialize, especially because the bigger power systems needed for cars or generators use lots of parts and, so far at least, have been prohibitively expensive to produce.