Tesla now offers a new Battery for Roadster owners as of September 2015. With about 40% more power, it provides about 35% more range. The original Roadster range was 245 miles (from the EPA program valid at the time of production). A 35% range improvement would boost the range to 330 miles (our analysis).
The cost of the upgrade is $29,000, which includes all parts and labor. The upgrade also includes removal, upgrade, and reinstallation of the PEM (Power Electronics Module). Tesla states the upgrade is made at its cost and it does not intend to make a profit on this upgrade.
New battery packs are hand-built at Tesla’s Fremont Factory. The upgrade should take about two days after all the parts are on hand at the local service center.
Retrofit Details at Tesla Motor’s Site
As of 2019, this option is sold out, and it’s not clear that Tesla will make any more.