Short answer is I agree with
@Seastormer
Long Answer
From the 2014 Manual
Charging the battery
Terminals for charging the battery are fitted in the engine compartment.
– Note the warnings ››› in Important safety
warnings for handling a vehicle battery on page 206 and ››› .
– Switch off all electrical devices. Remove the
ignition key.
– Raise the bonnet ››› page 199.
– Open the battery cover.
– Connect the charger clamps as described to the positive pole of the battery (+) and
exclusively to an earth on the bodywork (–).
– Only use a charger which is compatible for use with 12 V nominal voltage batteries.
The charge must not exceed a voltage of 15V.
– Now connect the battery charger to the power socket and switch on.
– After charging the battery: switch off the battery charger and disconnect the power socket cable.
– Finally disconnect the charger cables from the battery.
– Replace the battery cover correctly.
– Close the bonnet ››› page 199.
Important: Before you charge the battery
make sure you read the manufacturer's instructions
for using the battery charger.
WARNING
Never charge a battery that has frozen: replace
battery! Failure to do so may lead to an
explosion.
Note
Use only the terminals in the engine compartment
to charge the battery.