Tesla Shows Off The Model S Glider And 8,000 Odd Panasonic 18650 Cells That Power The Car Earlier This Year In Geneva
Batteries in general lose capacity over time and use, which for electric cars means lower range with every mile driven and every passing day.
How quick the capacity fade is remains mostly unknown as manufacturers typically provide only general information.
In the case of Tesla Model S, the warranty does not cover capacity fade.
Every car is used in different way, in different temperature ranges etc., so there is also no simple function that allows us to figure on what to expect in terms of capacity loss..
Over on the Steinbuch blog, we recently found links to reports based on data from Model S owners.
The first graph above (here is the interactive version) is described as follows:
"From the figure it is clear that the degradation slows down with more driven km. After say 80.000 km (50.000 miles), the overall range degradation is seen to be approximately 6%, with a rate of appr 1%/50.000 km (1%/30.000 miles) from that point onwards."
It's hard to say how accurate these results are, but a loss of just several percent by 80,000 km (50,000 miles) should be considered as more than acceptable.
Especially positive would be that the pace of capacity fade seems to be stabilizing, but is it possible to extrapolate that you could drive 280,000 km (over 170,000 miles) and still be at some 90%?
We think that there are still too many factors and not enough data to say what to expect in the longer term.