In my humble opinion, TSLA is the master cheater in respect of their "advanced battery technology". Generaly, the Lithium battery degrades in 2 ways: first it is about number of charging cycles. Lithium battery cell can last about 500-600 cycles. On top of that, the battery degrade based on its age, disregards on number of cycles. So it does not really matter, how the battery is used, in about 10 years is ready to go. For more detail, please see the "battery university" web site.

TSLA is well aware of this fact. Their batteries do not carry any "magic sauce". In order to avoid warranty costs, they put more cells into the battery to make sure, it last at least 8 years (which is the warranty). And they do those 500k miles on a big battery pack really fast the battery will survive such test.

I would definitely kept myself away of any EV, 10 years old.