Motorola taking the lead on battery technology
Jan 20, 2000 at 04:00 GMT
Here's an interesting technology press release which may well effect digital cameras: Scientists at Motorola Labs and Los Alamos National Laboratory have developed a new, miniature fuel cell that may one day replace the traditional batteries that now power everything from cellular phones and laptop computers to portable cameras and electronic games.
The energy density of these new fuel cells is 10 times that of conventional rechargeable batteries. At the same time, they will be significantly lighter in weight and less expensive to purchase.
The new fuel cells, each measuring about one inch square and less than one-tenth of an inch in thickness, are powered by liquid methanol (wood alcohol) and can easily be installed into numerous existing and future electronic devices. Use of the fuel cells, for example, could safely power a cellular phone for more than a month and eliminate the need for battery chargers and a/c adapters.
"Manufacturers are constantly developing new features for portable electronic equipment that require more power and longer operating life," said Bill Ooms, director of Motorola's Material, Device, and Energy Research. "These fuel cells have an amazing ability to produce energy for longer periods of time while weighing far less than conventional batteries."
The new fuel cell uses a reservoir of inexpensive methanol that, when combined with the oxygen in the air, produces electricity. Since fuel cells have low voltage outputs, typical designs normally would require stacking several cells together to increase voltage. However, Motorola Labs has designed unique circuitry that efficiently converts the low voltage of a fuel cell to the higher voltage required to replace conventional batteries and directly drive portable electronics.
This "air breathing" fuel cell was developed at Los Alamos National Laboratory. The highly simplified and miniaturized design eliminates the need for air pumps, heat exchangers and other complex devices that previous fuel cells required and therefore disqualified them from successful use in today's small portable electronic products.
It's envisioned that the methanol required to run electronic devices could be packaged in small, inexpensive cartridges and purchased at the same locations consumers now purchase traditional batteries. The technology has the same consumer-friendliness as batteries: the quiet and clean conversion of a material's chemical energy into electricity.
Motorola Labs, together with members from Motorola's Energy Systems Group have assigned a research team to Los Alamos to form a center of excellence that plans to drive this new technology into the marketplace.
The advanced direct methanol fuel cell technology base at Los Alamos National Laboratory was created with support from the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy, and the Defense Science Office of the Defense Advanced Research Projects Agency (DARPA). The University of California operates Los Alamos National Laboratory for the U.S. Department of Energy.
Motorola, Inc. (NYSE: MOT) is a global leader in providing integrated communications solutions and embedded electronic solutions. Sales in 1999 were $30.9 billion.
How It Works
A fuel cell converts chemical energy directly to electrical energy. The basic concept of a fuel cell originated in 1839, but practical applications came from NASA in the early days of space flight.
Many kinds of fuel could be used in a fuel cell. The most active fuel for fuel cells is hydrogen. Recently, methanol has been considered as an alternate fuel because it has a higher energy density than hydrogen (that is, more energy for a given size and weight compared to hydrogen).
A direct methanol fuel cell converts the energy in methanol directly to electricity and operates at normal room temperatures. A catalyst (typically a mixture of platinum and ruthenium) is used to react a dilute mixture of methanol and water to form carbon dioxide, protons, and electrons, which provide the electrical current. The protons are conducted through a proton-conducting organic membrane to another platinum catalyst where the protons combine with oxygen from the ambient air to form pure water. Some of the water is recycled back to mix with the methanol, and the excess water evaporates as water vapor in the air.
The key technical challenges of fuel cells are to make them at a cost lower than rechargeable batteries. Also, the entire fuel cell system needs to be miniaturized to fit into today's small portable electronic equipment. Of course, one wants very high efficiency in the conversion of methanol to electricity and a very long operating life for the system.
For more detailed information on the general topic of fuel cells, a booklet is available from Los Alamos National Lab entitled "Fuel Cells - Green Power". It is available on the Web at http://www.education.lanl.gov/resources/fuelcells/ .