The starter battery is a traditional 12 V battery.
Removal
First of all: Take the remote control key from the ignition switch and wait at least 5 minutes before any electrical connections are touched - this is because the car's electrical system needs to store the necessary information to control modules.
Open the clips on the front cover and remove the cover.
Release the rubber moulding so that the rear cover is free.
Remove the rear cover by screwing one quarter turn and lifting it away.
Warning
Connect and remove the positive and negative cables in the correct order.
Detach the black negative cable.
Detach the red positive cable.
Detach the ventilation hose from the battery.
Loosen the screw holding the battery clamp.
Move the battery aside.
Lift it up.
Fitting
Lower the battery into the battery box.
Move the battery inward and to the side until it reaches the rear edge of the box.
Tighten the clamp that holds the battery.
Connect the ventilation hose.
Check that it is correctly connected to both battery and outlet in the body.
Connect the red positive cable.
Connect the black negative cable.
Press in the rear cover. (See earlier section "Removal".)
Fit the rubber moulding. (See "Removal".)
Align the front cover and secure it with the clips. (See "Removal".)
For more information on the car's starter battery, see Jump starting with battery.