Is the 12-volt system separate from the drive battery in an EV?

Is the normal 12-volt battery system separate from the drive battery on my 2025 Peugeot E-Rifter? I want to add a charging socket to the 12-volt battery as it often gives a message of low battery power if sitting in the car and using your phone for a while.

Thanks

PETER CLARK (Waltham Abbey)

Apr 2026 Filed under: electric cars

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Expert answer

Hi Peter,

Yes, the two electrical systems are separate, though the 12-volt battery is kept charged up by the drive battery when the car is 'turned on'. 

When the car is turned off, but you are using features that draw energy from the 12-volt battery, it will of course lose charge and the car monitors that and protects the battery by turning off completely. 

You could in theory add a suitable charger to allow use of the car as you are doing, or you could just have the car turned on every now and then when stationary to allow it top up the 12-volt battery automatically itself.

I'd be inclined to do the latter.

Shane O' Donoghue - Complete Car Advisor