Developments to Watch

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.EDITED BY ROBERT BUDERI