Tesla has announced a new upgrade it will be making in 2015, for its out-of-production electric sports coupe, the Tesla Roadster. This announcement comes as an unusual but exciting news for owners of the car, as it is very rare that a car manufacturer does something to upgrade a car which is no more in production.
With the Roadster 3.0 package the Tesla Roadster will become upgradable to a 70-kWh battery, a few exterior body-parts for aerodynamic enhancements and low-rolling resistance tires.
The new cell has 31% more energy than the original Roadster cell. With a retrofit aero kit, the drag coefficient (Cd) of 0.36 is expected to drop to 0.31. The original Roadster tyres have a rolling resistance coefficient (Cr) of 11.0 kg/ton, which will reduce to about 8.9 kg/ton with new low-rolling resistance tyres.
With these improvements, the company expects the Roadster to get 40-50% improvement in the driving range and is confident that the Roadster 3.0 will have a driving range of over 400 miles (655 km).
More information is available in the press release below.
Roadster 3.0 – Press Release
The Roadster 3.0 package applies what we’ve learned in Model S to Roadster. No new Model S battery pack or major range upgrade is expected in the near term.
Battery technology has continued a steady improvement in recent years, as has our experience in optimizing total vehicle efficiency through Model S development. We have long been excited to apply our learning back to our first vehicle, and are thrilled to do just that with the prototype Roadster 3.0 package. It consists of three main improvement areas.
The original Roadster battery was the very first lithium ion battery put into production in any vehicle. It was state of the art in 2008, but cell technology has improved substantially since then. We have identified a new cell that has 31% more energy than the original Roadster cell. Using this new cell we have created a battery pack that delivers roughly 70kWh in the same package as the original battery.
The original Roadster had a drag coefficient (Cd) of 0.36. Using modern computational methods we expect to make a 15% improvement, dropping the total Cd down to 0.31 with a retrofit aero kit.
3. Rolling Resistance
The original Roadster tires have a rolling resistance coefficient (Crr) of 11.0 kg/ton. New tires that we will use on the Roadster 3.0 have a Crr of roughly 8.9 kg/ton, about a 20% improvement. We are also making improvements in the wheel bearings and residual brake drag that further reduce overall rolling resistance of the car.
Combining all of these improvements we can achieve a predicted 40-50% improvement on range between the original Roadster and Roadster 3.0. There is a set of speeds and driving conditions where we can confidently drive the Roadster 3.0 over 400 miles. 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.
We are confident that this will not be the last update the Roadster will receive in the many years to come.