Whether you're talking on a mobile phone, listening to tunes on a media player or typing on a notebook, it's a good bet that the device's battery won't last as long as you'd like. However, that will change over the next few years, as fuel cells designed to power mobile gear start to become common.

In particular, direct methanol fuel cells (DMFC) will deliver as much as 10 hours of power using a thimbleful of methanol -- that's two to three times the life of current laptop batteries. Better still, when a fuel cell runs out of power, you don't have to find an AC outlet and wait for a battery to recharge. Rather than taking the plug-and-wait approach, you'll either refill the tank from a larger canister or simply insert a new, full reservoir. You can run your mobile gear as long as you have methanol to satisfy the fuel cell's thirst.

For the past decade, fuel cells have seemed to be tantalizingly close to commercialization, but they never quite made it to market. Finally, they really do appear ready, with several major manufacturers of batteries, fuel cells and mobile devices saying that 2009 will be the start of the fuel-cell era.

This could change how we think about mobility, freeing us from the tyranny of short-lived batteries and the need to find an electric outlet. In other words: Road warriors, rejoice! You have nothing to lose but your batteries.

Here's the lowdown on this promising technology, how it will affect your mobile lifestyle and when you likely will be able to use it.

Bye-bye batteries

"The long-term vision is that anywhere people are using batteries today, they can be replaced by fuel cells," explains Peng Lim, chief executive officer at MTI Micro Fuel Cells. MTI is working on internal and external fuel cells for powering mobile gear.

"The transition to fuel cells has already started, although it won't happen overnight," says Sara Bradford, principal consultant for the energy and power systems group at market analyst firm Frost & Sullivan, noting that the first external fuel-cell power packs are just hitting the market.

For instance, the Medis 24-7 Power Pack can pump out up to 5.5 volts of pure, clean power. At US$30, it should be good for about 30 hours of phone use, or double that for a media player. After that, a US$20 refill tank is all you'll need -- that tank will last another 60 hours.

This system isn't aimed at being a primary source of mobile power, but an alternative source of power for emergencies or if you're away from an electrical outlet for a long period of time. But at 6.5 ounces, it weighs as much as a smart phone.

The Medis system is an external add-on; the next step is refillable fuel cells built into mobile devices.

"Next year, look for a smart phone that has a fuel-cell option," says Sean Collins, vice president for business development at Toshiba America Electronic Components. While the engineering and marketing details haven't been worked out, Collins adds that several phone makers are looking to sell products with a traditional battery as well as an optional fuel cell that fits in the same space.

Further out on the horizon, the technology will get really interesting for road warriors, with mobile equipment designed for and fully powered by fuel cells. "In three to five years," Collins explains, "equipment that runs solely on fuel cells will hit the market."