Model S delivered Jul 2016, 1st battery lasted 13 months, 2nd battery lasted 10 months and contrary to what I was told at purchase I now have to pay a ranger fee that is over $550. No after market gear installed. Definitely a design problem, a 12v lead acid battery on a charger can last much longer than this even under load. I've changed my mind on this car and no longer recommend it for people not near a service center, the ranger fee is just too expensive. Only 16,000 miles and I have had 5 service problems, much worse than my Toyotas. It's a shame...for the want of a nail....