Improved battery technology can provide 31 percent more energy than the original Roadster cells, the company said in a blog posted Friday on its website. Combined with an aerodynamics kit, new tires and improvements to wheel bearings and brakes, range can be increased as much as 50 percent compared with the original Roadster, Tesla said.
The company didn't say what it will charge for the upgrades, which it collectively calls Roadster 3.0.
"There is a set of speeds and driving conditions where we can confidently drive the Roadster 3.0 over 400 miles," Tesla said in the blog item. "We will be demonstrating this in the real world during a non-stop drive from San Francisco to Los Angeles in the early weeks of 2015."
Tesla sold about 2,500 of the $109,000 Roadsters, which were built on a Lotus chassis. The car was introduced in 2008, and bringing it to market amid a global recession amplified cost overruns and production delays, nearly tipping the company into bankruptcy. Tesla went public in 2010 and reported its only net income for the first quarter of 2013.
Tesla rose 2.5 percent to close at $227.82 on Friday.
The shares have recovered after falling 23 percent in the four weeks ending Dec. 16 when they closed below $200 for the first time in more than half a year. The shares rose 48 percent for the year through Wednesday, quadrupling the 12 percent gain by the Russell 1000 Index.
The Model S, the only car Tesla currently has in production, will get a battery-pack up grade eventually, though not soon, CEO Elon Musk said in a tweet over the weekend. Autonews/Bloomberg