Last week we reported that Tesla was planning a significant update of its first model, the Roadster. And just a couple days after Christmas, Tesla has released full details. Called the 3.0 Package, the upgraded Roadster EV is the vehicle it should have been all along. To Tesla's credit, it hasn't forgotten about the Roadster or its owners. This upgrade pack adapts new battery cell technology that improves its range to over 400 miles. Energy capacity has also been boosted by 31 percent, now delivering 70kWh, up from 53kWh.

In addition, Tesla has improved the Roadster's aerodynamics with a retrofitted aero kit. This delivers a 16 percent reduction in drag coefficient. There are also new tires that improve the rolling resistance coefficient by almost 20 percent. Compared to the original Roadster launched back in 2008, Tesla claims an overall 40- to 50-percent improvement in range. An official demonstration of the Roadster 3.0's abilities will take place early next year with Tesla driving it non-stop from San Francisco to Los Angeles, about 380 miles. If all goes to plan, owners will be able to take their Roadsters in for the upgrades this spring once the new battery pack has been fully tested and safety certified.