Tom Saxton's Roadster battery study showed that degradation is more closely related to mileage than time, with an expectation of 80-85% capacity over 100,000 miles. The Model S battery has improved chemistry and should easily beat that.
http://www.pluginamerica.org/surveys/batteries/tesla-roadster/PIA-Roadster-Battery-Study.pdf
Personally I've seen zero degradation on my five year old pack.
That is some awesome data collection and presentation ! Thanks for the link.
Thank you. So then my original estimate may be correct. Not as terrible as it may seem.
Max*, it does indeed appear you were right, that battery degradation is independent of time.
(We can apply the conclusions of the Roadster battery data to the Model S, right ? Same cells, both has a TMS, and same-or-lower C-rate for the Roadster. Something I'm missing ?)
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