Odds are, there's more than one company that makes/has made batteries for Mercedes.
It usually goes like this:
- Merc plans to build x cars next year
- for those cars they need x + some spare batteries
- the batteries need to have a size this-and-that, and electrical capacity so-and-so
- Merc wants y number of batteries delivered every other day
- Merc asks several different battery manufacturers if they can deliver batteries according to above, and what they would charge for it
- the winning company, usually the lowest bidder, gets to deliver batteries for the length of the contract.
- when the contract is about to run out, the whole process is repeated again, but maybe this time another another manufacturer offers a sweeter deal, and gets the job.
