OEM Batteries are White for Lead Acid & Black for AGM. They are Exide batteries at the minute, they may have been Bosch in the past. A bit like the switch to Sheel for the "official" oil now, used to be Castrol up to Christmas. BMW won't cover warranty work on cars that get Castrol oil in the dealer anymore apparently.

Remember this post?:

http://www.bmwhaus.ie/forum/showthread.php?tid=5046