To prove that the Model S sedan isn’t vaporware, Tesla rolled out a bare aluminum bodyshell at Cobo Hall, complete with all the car’s running gear. Tesla says that weight reduction is critical with an electric car—those batteries are heavy, after all—so aluminum made more sense than steel. The bodyshell is composed of stampings and extrusions that are welded, bonded, and riveted together. This structure will form the basis of a whole family of cars, apparently.
The neatest feature of the S is the battery pack, which is bolted to the underside of the body and is very slim, in an attempt to lower the car’s center of gravity. The pack itself has 7000 cells and is an evolution of the unit fitted to the Tesla Roadster. There will be three versions of the S, with ranges of 160, 230, and 300 miles, although Tesla admitted that it takes about 18 hours to charge the 300-mile battery on a 120-volt feed.
The control-arm front suspension also uses a lot of aluminum components, while the rear suspension is mounted on an aluminum subframe that also carries the 306 pound-feet AC electric motor, single-speed gearbox, and power electronics. Tesla says that 54 percent of the weight is distributed at the rear of the vehicle.
Because there’s no conventional engine, the front hood covers a luggage compartment, like a Porsche 911′s, only bigger. In total, Tesla says the S has 30 cubic feet of luggage space, which is small-SUV-like. The company also says the vehicle weighs 4000 pounds, which takes some believing when you see the size of the battery pack.
The Model S is still slated to go on sale in 2012, at a predicted volume of 20,000 cars a year. The stated price tag of $57,000 (before the federal tax credit) seems awfully low when you look at the body and all the technology incorporated in the vehicle, especially at these volumes. Perhaps it will be vaporware, after all. — Mark Gillies