New Fuel Cell Promises Cheap, Portable Power

Compact fuel cells that convert a mixture of gases into electricity could one day power everything from portable telephones to electric cars, using a new technology unveiled Wednesday by scientists for Bell Communications Research in New Jersey.

The technology, still in the prototype stage but detailed in an article in today’s edition of the weekly journal Nature, could result in low-cost, clean and lightweight fuel cells that would be a significant improvement over batteries or other fuel cells, said Christopher Dyer, the principal researcher at the laboratory, which is usually called Bellcore.

“The interesting thing about this technology compared with other kinds of electrical generators, such as a conventional fuel cell, is that it should be possible to make them very cheaply,” said Dyer from the lab in Morristown, N.J.

A fuel cell generates electricity through chemical reactions among gases or other chemicals. Unlike conventional batteries, a fuel cell does not need to be recharged with electricity when it runs down; it merely needs another dose of gas or chemicals.

The experimental Bellcore fuel cell is still only a tiny laboratory prototype, but tests suggest that it would carry a lot of electricity for its weight and size: about 100 watts per kilogram (2.2 pounds), or one to 10 watts per cubic inch.

The device consists of an ultra-thin, gas-permeable membrane of aluminum oxide--less than one one-thousandth of an inch thick--sandwiched between two layers of platinum. A mixture of hydrogen and air is circulated around the film. The resulting chemical reaction combines hydrogen and oxygen into water, releasing electricity.

Unlike regular fuel cells, the reactant gases do not need to be separated, a process that adds significantly to the cost of conventional cells, Dyer said.

And unlike regular batteries, the fuel cell uses hydrogen and air, rather than expensive and toxic metals such as cadmium and lead. Tests are proceeding on a fuel cell that would employ methanol and produce nothing more harmful than carbon dioxide, Dyer added.

Dyer insisted that the technology exists to manufacture fuel cells using the Bellcore approach, although further tests must be conducted and technical and engineering studies finished to scale the prototype up to commercially useful sizes.

Production costs could be kept low compared to existing fuel cells, Dyer added. Eventually, he estimated that Bellcore fuel cells could be produced for less than $1,000 per kilowatt, compared to between $3,000 and $5,000 per kilowatt for existing fuel cells.

The Bellcore fuel cell’s relatively low cost and light weight would make it ideal for use in electric vehicles, Dyer added. Existing and proposed electrical vehicle designs call for comparatively heavy batteries similar to the lead-acid batteries used by conventional autos.

The fuel cells could also be adapted for use in portable telephones. When the charge runs down, they could be rejuvenated with a shot from a gas cartridge.

The fuel cell technology could also be used to power everything from integrated circuits to home generators running on natural gas.

It was devised at first to provide backup power for telephone company equipment in the event of extended power outages from natural disasters, said Tom Taylor, district manager of Bellcore’s energy systems technology unit.

Such equipment is now powered by batteries, but the batteries eventually run down and must be recharged electrically. Fuel cells could be powered back up by adding more gases and could run twice as long in less space.

Bellcore provides technical support to regional telephone companies.

Five other kinds of fuel cell technologies exist, but they are all relatively expensive, said Edward Gillis, manager of the fuel cell program at the Electric Power Research Institute in Palo Alto, a group funded by the utility industry. Fuel cells are used to provide electrical power to the space shuttle, to West German submarines and to Japanese buildings, among other uses.