The battery in a hybrid and an electric car

Many hybrid and electric-car owners think that since the car has a big drive battery, an ordinary battery doesn’t concern them. That’s a mistake — these vehicles have two different batteries, and it’s the smaller one that most often causes trouble.

Two different batteries

The traction (high-voltage) battery drives the car and is a separate system, serviced differently. Alongside it, though, is an ordinary 12 V battery that powers the electronics, computers and starting systems — and it wears out like in any combustion car.

It’s the 12 V battery that immobilises the car

Paradoxically, it’s not the powerful drive battery but the small 12 V one that most often stops a hybrid or EV “waking up” in the morning. Flat or worn, it cuts power to the electronics needed to start the whole system.

• Traction battery — drive, a separate system, not replaced like the 12 V
• 12 V battery — powers the electronics and “wakes” the car
• In hybrids the 12 V is sometimes smaller and more sensitive
• Its wear shows up as in any ordinary car

In a hybrid and an EV it’s the modest 12 V battery, not the drive battery, that most often decides whether the car starts in the morning.

A 12 V change like in any car

The 12 V battery in a hybrid or EV is selected and replaced on the same principles as in a combustion car — allowing for the type and any registration. We’ll select the right battery and replace it with call-out.