One of the things Tesla has long said it would do is offer a Roadster upgrade as a thanks to the super-early adopters who helped Tesla get off the ground. That’s supposed to include a longer-range battery, improved aerodynamics, and better tires.

Tesla Roadster 1

Tesla Roadster 3 battery upgradeI don’t think anyone sane can blame Tesla for taking a while to get to this, considering the mammoth undertakings it is attempting (trying to get the gull-wing Model X into production; preparing for the Model 3; building a battery Gigafactory; introducing and developing Tesla Energy; and building out a massive global network of Superchargers, stores, and service centers), but I’m sure a number of Roadster owners have been eager for the details and offer.

In an email sent yesterday to Roadster owners, the battery part of that equation is now worked out. The upgraded battery pack on offer has 40% more capacity than the original battery pack, and will increase range ~35% once you take the extra weight into account. It will cost $29,000 (including labor) with Tesla not taking any profit on it and building the battery pack by hand.

“Owners need to place a $5,000 deposit for the company to start building the battery pack and plan the upgrade. On the Tesla Motors Club forum, a few owners have already confirmed having placed their deposit,” electrek’s Fred Lambert writes.

Tesla Roadster 3

“Tesla sold roughly 2,400 Roadsters during its original run between 2008 and 2012. It will be interesting to see how many owners will choose to upgrade the battery pack, but apparently the company is not expecting a lot of takers with a planned production of only ‘2 or 3 per week’. At this rate, it would take 3 years just to replace 20% of the battery packs.”

We’ll see what’s next for these initial Tesla buyers (and those who acquired Roadsters used).

Images: orange & white Roadster via Darren Brode / Shutterstock.com; blue Roadster via betto rodrigues / Shutterstock.com