Depending on how you look at it, Tesla Motors' [NSDQ:TSLA] announcement that its new Model S 75D is really just a software update over the 70D is either great news or a shady move.

The new 75D doesn't actually have a different battery than the 70D. Instead, 75Ds will simply contain software that unlocks the extra 5 kilowatt-hours of battery capacity over the 70D. Further up is the 90D and P90D models which have their own battery.

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Order a new 75D and you'll pay $3,000 more than the 70D, but you'll gain an extra 19 miles of range. That brings the total to 253 miles for rear-wheel-drive models and 259 miles for all-wheel-drive variants with their dual motors.

2016 Tesla Model S

2016 Tesla Model S

Owners of 70Ds will be able to update their cars to 75Ds for $3,250, although Tesla is extending the from-the-factory $3,000 offer to those who have already placed an order for a 2017 Model S 70D.

READ: Tesla targets 90,000 cars this year, 500,000 as early as 2018

Those who pop for the upgrade will also receive 75D badging, which presumably means they'll get a "5" badge to replace their current "0" badge.

What this means is that Model S 70D owners have actually been driving around with an extra 5 kwh of lithium-ion battery capacity right under their noses (or under their feet, as it turns out).


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