[jillesvangurp]

4000 cycles is pretty impressive. Worth pointing out just how good that is: if you fully charge the battery every day of the year, that would mean close to 11 years of very intensive use. 4000 times a typical maximum range of 250 miles would mean driving a million miles. Some taxis get that kind of mileage of course. But most drivers would take quite a bit of time to get there.

In short, if you are lucky enough to own a vehicle with such a battery, it needing replacement is not going to be an event that you should have to worry about for decades if you drive it normally. Which would mean doing about 14K miles per year; or about 71 years.