A Guide to Jump Starting an EV
We explain if jump starting is necessary for electric cars and whether you can use an electric vehicle (EV) to jumpstart another car.
Last updated: Jun 17, 2024 • 4 min read
Summary
You can jump start an EV with another car, but manufacturers generally advise against jump starting an ICE car or an electric car with another EV. It can cause damage to the main and smaller battery, software and other components.
What is jump starting?
Both, EVs and internal combustion engine (ICE) cars, have a small battery that helps the vehicle start its motor or engine and provides some energy when the engine or motor isn’t turned on but is using its lights, locks and other parts. When this smaller battery is dead, the vehicle won’t be able to turn on and will need a jump start to get back on the road.
Jump starting involves using another car’s battery and jumper cables to give the dead battery temporarily enough power to start the engine. Depending on the reason for why the battery has run out of energy, it can be recharged with the power generated from driving or will have to be replaced if faulty.
Can you jump start an EV?
Luckily, most EVs carry the same type of 12V battery you’ll find in ICE cars, meaning you can technically jump start it the same way. This battery is different to the larger, main battery pack used to power the motor of an EV, which is typically made from lithium-ion. There are exceptions, with some luxury EVs using a small lithium-ion battery instead of the 12V sulfuric acid-based battery found in the majority of cars.
Although an EV’s smaller battery rarely runs out of charge completely, it can happen. The most common cause is the main battery pack being left on zero percent charge over an extended period of time, which will eventually lead to the 12V battery dying. In this case, you can either jump start your EV with another car or use a trickle charger to resupply enough energy to the 12V battery to start the motor and fully recharge it that way.
How to jump start an electric car
Before you attempt to jump start an electric car on your own, check if you have an existing maintenance package or roadside cover that will provide professional assistance. Performing a jump start on an electric car could void your warranty or cause your insurance to be cancelled. Always check your policy before you attempt to do this.
If you have to, here are the steps for how to jump start an electric car:
Park your EV on a flat surface. Avoid hills or sloped areas.
Connect the jump cable to the positive terminal on the 12V battery on the EV side.
Then connect the other end of the jump cable to the positive terminal on the 12V battery on the ICE car side.
Now, connect the other jump cable to the negative pole on the ICE car battery.
On the other side, connect the opposite end of the jump cable to the bodywork of the EV.
Finally, start the ICE car engine to jump start your EV.
If your electric car doesn’t come on straight away, switch it off and wait around 15 seconds before repeating the process. Leave your EV on for a minimum of 20 minutes to allow the 12V battery to recharge enough.
Can you jump start using an electric car?
While it’s possible to jump start another car using an EV, most manufacturers strongly advise against it and will void your warranty if you do so. There are several reasons why it isn’t a good idea to jump start using an EV.
ICE car batteries are made to provide a burst of energy to ignite the fuel that runs an engine. An EV’s 12V battery, on the other hand, isn’t meant for this purpose and simply doesn’t provide enough energy to jump start another EV or petrol or diesel car. Attempting to jump start another car can cause significant damage to the smaller battery in an electric car.
Jump starting another car with your EV can also cause issues with the battery management system and DC to DC converter in your electric car. This converter is crucial to many smaller functions in an EV. If it breaks or becomes faulty, you may not be able to perform basic tasks, such as using your lights, heating and cooling/heating, etc.