Battery OEM BMW or OEM FORD

Always read your manual/mfr suggestions for battery charging and longevity.

For Li-ion you generally should charge no more than 80% (some mfg hide 10% via software like Ford, so you charge to 90%). Also, limit fee cycling these types too, regularly you should DC to about 50% max. Occasionally deep cycling and full charging is fine. Should limit DCFC also.

For about a month I have owned a 2016 REx whose 60 Ah battery is supposed to get 72 miles. This week I fully charged it and have been commuting four four days without topping up. Today the REx kicked in with the trip meter at 73.3 miles. This was a mixture of city traffic jams and short bursts on the carriageway, mostly with the air con on and mostly in Comfort mode. So I'm pretty pleased.

I am still on my original battery in my 2007 335i w/ 87k miles.