A New Spin On Electric Car Batteries
Now that most major carmakers are planning electric vehicles, work is proceeding rapidly on better batteries. On June 23, American Flywheel Systems Inc. in Seattle received a patent on a battery it says will let cars get 600 miles per charge--five times the current distance--without the toxic-waste and corrosion problems of lead-acid models.
The battery, charged from a 110-volt outlet, relies on kinetic energy. During charging, electrical current causes two rotors, suspended by magnetic bearings in a vacuum, to spin at high speeds. Once the charge is complete, the rotors continue spinning. Twenty such batteries generate enough energy to drive a car-size motor for 43.6 kilowatt hours, vs. 13.6 kwh on General Motors Corp.'s Impact prototype electric car.
A federal research program on the technology ended in 1983 before delivering a commercial product. Edward W. Furia, American Flywheel's president, attributes his better luck so far to computer-aided engineering, new composites that make the battery lighter, and advanced magnetic bearings. He hopes to build a demonstration model within a year.