for National Geographic News
As tech gadgetry from MP3 players to PDAs continues to evolve, the lithium- based batteries that run these power-thirsty gizmos are increasingly unable to keep up. Just think how annoying a laptop running out of juice can be.
Now chemical engineers at Purdue University in West Lafayette, Indiana, say they have come up with a solution to make our electronic devices dramatically more portable.
Their new method produces hydrogen for fuel cells that would automatically recharge batteries in portable electronics, such as notebook computers, eliminating the need to use a wall outlet.
"Currently, rechargeable batteries need a relatively long time to be charged," said Evgeny Shafirovich, one of the Purdue engineers who worked on the project. "The use of fuel cells and combustion-based hydrogen generators makes it possible to eliminate the need for plugging into the [power grid]."
In addition to increasing the portability of gadgets, the technology could also have important environmental benefits. Hydrogen can be produced from renewable energy sources and thus help reduce the emission of harmful greenhouse gases.
Fuel cell technology has, for example, long been touted as a future solution to automobile pollution. Applying similar technology to electronic devices may help lower demand for electricity from environmentally harmful power plants.
"If a hydrogen economy can be realized, the environmental benefits in terms of reduction in global warming gases is enormous," said Jay Gore, a mechanical engineering professor at Purdue who was not involved in the project.
Either methanol (wood alcohol) or hydrogen can be used for the new fuel cell technology, which provides a much higher energy-output-to-weight ratio than lithium-based batteries.
The methanol approach, however, has several drawbacks, including low power density (power ouput relative to a fuel cell's size) and other technical challenges. It also gives off carbon dioxide, a pollutant, as a byproduct.
The problem with hydrogen, by contrast, has always been storage. It is impossible to use high-pressure hydrogen gas containers or liquid hydrogen in portable electronic devicessuch devices would be bulky or dangerous.
The Purdue scientists have combined two previously known methods for producing hydrogen. Their technique uses the chemical compound sodium borohydride in a gel created by combining water with a water-absorbent thickener and aluminum particles.
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