The battery should be in the hatch compartment (behind the rear seats), under the floor mat. Disconnect the negative terminal (black), then the positive terminal (red). Remove the battery, and install the new one in the same position. Reconnect the positive terminal, then the negative terminal. NOTE: The terminals are also designated by plus or minus symbols.
2005 Mini Cooper replace car battery. Alternative to MINI part
Batteries Plus
I will assume you mean "Does a Mini Cooper have a battery?" Yes, they do.
The 2004 MINI Cooper has 16 valves.
The 2004 MINI Cooper is a gas-powered vehicle.
The 2004 MINI Cooper has an inline 4 engine.
The 2004 MINI Cooper has a 5-speed manual.
The height of the 2004 MINI Cooper is 4 ft. 7.9 in. (55.9 in.).
The 2004 MINI Cooper has single overhead cam (SOHC).
The 2004 MINI Cooper has a drag coefficient of .36 Cd.
The 2004 MINI Cooper's turning circle is 35 ft..
The 2004 MINI Cooper is 11 ft. 10.8 in. (142.8 in.) long.