I just had to replace my battery in my 05 MC (non S). As I read on other posts, the options are not that simple or cheap. To make a long story short ,the MINI dealer sold their battery for the same as Autozone or Advanced Auto. I just bought from the dealer so i was insured proper fitment and venting.

MINI battery
Part Number: 61-21-7-591-081
Height: 7-1/2 in.
Length: ?? in.
Width: 6-15/16 in.
Cold Cranking Amps: 480
Cranking Amps: ??
Warranty: 2 years
Vent Hole: yes
Core Charge: none
Cost: $145
Made By Exide

Here are some details on other options:

Autozone
Model: Duralast Gold
Part Number: H5-DLG
Height: 7-1/2 in.
Length: 9-11/16 in.
Width: 6-15/16 in.
Cold Cranking Amps: 650
Cranking Amps: 750
Warranty: 3 year
Vent hole: unknown (visible in photo but on opposite end)
Core Charge: $5
Cost: $145

Advanced Auto Parts
Model: AutoCraft Gold
Group Size: 47H5
Height: 7-1/2 in.
Length: 9-9/16 in.
Width: 6-15/16 in.
Cold Cranking Amps: 520
Cranking Amps: 650
Warranty:3 year
Vent hole: unknown (visible in photo but on opposite end)
Core Charge: $12
Cost: $145

NAPA
Part Number: 7547
Height: 7-1/2 in.
Length: 9-9/16 in.
Width: 6-15/16 in.
Cold Cranking Amps: 750
Cranking Amps: ?
Warranty: 75 months
Vent hole: unknown (visible in photo but on opposite end)
Core Charge: ?
Cost: ?

AC Delco
Model: 47-6YR
Height: 7-1/2 in.
Length: 9-9/16 in.
Width: 6-15/16 in.
Cold Cranking Amps: 480
Cranking Amps: 625
Warranty: ?
Vent hole: ?
Core Charge: ?
Cost: ?

 

Thanks for the list!

-Jorge

 

It would be interesting to see the weights of each of these battery choices too.