For more on electric vehicles, see the slideshow ELECTRIC VEHICLES MOVE FORWARD...SLOWLY.

PHOTO: General Motors

Electric-car news is coming thick and fast. Two major Japanese automakers pumped up their green credentials by offering up their EVs for limited tests in the U.S. market, while mighty General Motors opened its kimono a tiny bit more with a technical progress update on its Chevrolet Volt extended-range electric vehicle (E-REV). And a legal fight emerged into public view as Tesla Motors, of San Carlos, Calif., sued a former designer who launched his own plug-in hybrid car company.

Last month, Chevrolet updated 80 reporters from around the world on the progress of its much-touted Chevrolet Volt. With unprecedented openness, especially for a vehicle years from production, the company discussed its battery testing procedures, showed off the three-dimensional virtualization rooms that connect design teams around the world, and revealed a few glimpses of the latest Volt styling.

The message is that the Volt program is on course and that it's the company's “Number One priority project,” in the words of Volt global vehicle chief engineer Frank Weber. “This is not theory; this is real,” he stressed. Engineers are testing the two competing 16-kilowatt-hour battery packs—each 1.8 meters long (or just under 6 feet) and 170 kilograms (375 pounds)—around the clock. GM even provided details on the test cycles they're repeating, thousands of times, to pack 10 years' worth of customer use into the two-year test window that will permit a launch in late 2010.

Reporters also walked through GM's enormous wind-tunnel facility. Low aerodynamic drag is key to extending the Volt's range—at speed, it is more important than lower weight, due to aggressive regenerative braking that recaptures energy for recharging. GM's Bob Lutz admitted the “electric Camaro” shape of the Volt concept was far from aerodynamic, with a drag coefficient of 0.43, higher than most cars today. “It was a shoebox,” he said ruefully, promising a drag coefficient below 0.30—among the best in its class—for the final Volt.

In December, GM teased the press by showing the front corner of the latest styling model. It was smooth and swept-back compared with the angular concept. This time, chief E-Flex designer Bob Boniface briefly lifted the cover from a rear corner of a clay model being shaped by a numerically controlled milling arm while reporters watched. And visible in the wind tunnel was a third-scale model covered in camouflage tape, with an aerodynamics expert wielding a hose that sent propylene glycol mist over the car to show the airflow as a 50-kilometer-per-hour (31 miles per hour) wind roared over it.

What will the production Volt look like? If these models are indicative—and Boniface said “the body's not frozen yet, but it's close”—it seems shorter and stubbier than the concept. Its Kamm tail is an abrupt vertical plane behind the rear wheels, with a high deck lid (actually a hatch, as the Volt will be a five-door hatchback). Its swept front has a distinct resemblance to Saab styling (another GM marque), and the car's shape somewhat resembles…a Toyota Prius. Hmm.

One innovation is the lack of an exposed exhaust pipe. The car has one, of course, for its small combustion engine (which drives a generator to keep the car running by charging its battery pack once it has exhausted the 60 kilometers (about 37 miles) of electric range). But that tailpipe outlet will be hidden under the car, reinforcing the primacy of the Volt's electric drive.