These days the only real difference is the purity of the lead used in making the battery. Cheap batteries have very lower % of lead in the plates compared to high end batteries. The really expensive ones (normally used in stereo competitions more than most general auto use aka cranking) have 98 to 99% pure lead in the plates. These are not cheap usually in the $300 plus range. The dealerships batteries may be $300 but that's their inflated prices for a $100 battery. If they sold the high end ones it would probably cost $900 from the dealership
Also as mentioned for general over the counter batteries there aren't but 3 manufacturers and they put different stickers on them depending on who is selling the battery (autozone, walmart, etc)
Deka seems to make the higher end of the over the counter products from my research. Johnson Controls makes a good battery too its just not rated as high ah wise as the deka ones and the deka batteries seem to last longer.
I use walmart deep cycle marine batteries for instance to power my house. I have 32 of those all connected together for the house.