[F87source]

Originally Posted by CSBM5

Supposedly the same battery is used in both. 61212353812 is the P/N.

M2Comp battery

M2 battery

It's application is shown across a zillion other BMW models also.

No there's a 90ah battery as well (mine is 90ah), this was on the majority of cars early on I'll post the real OEM links in a bit. I've also just made some findings that'll I post shortly.