Owning an electric vehicle (EV) goes beyond simply charging it up—there’s more to maintenance than meets the eye. If you’re new to EVs or exploring options for your next ride, you might be surprised to learn that electric cars rely on a traditional 12-volt battery, just like their gas-powered counterparts, in addition to their high-voltage packs. When this 12-volt battery dies, your EV won’t start. Fortunately, jump-starting it is an option, even with help from a gas vehicle. Drawing from expert insights by Chris Hardesty in Kelley Blue Book, here’s everything you need to know about reviving your electric car battery safely and effectively.
Key Safety Tips for Jump-Starting an EV
Before diving into the process, let’s address critical safety points. First, never attempt to jump-start the high-voltage lithium-ion battery in an electric vehicle—it’s dangerous and unnecessary. Additionally, avoid using an EV to jump-start another vehicle’s 12-volt battery. As Hardesty explains, “The EV’s charging points are designed solely for jump-starting itself, not for aiding other cars.” The donor vehicle—typically gas-powered—must feature a 12-volt battery with a negative ground system, which is standard. Always consult your EV’s owner’s manual for model-specific instructions, as some require unique steps. Alternatively, a portable jump-start device works well for an EV’s 12-volt battery too.
Step-by-Step: Jump-Starting Your Electric Vehicle’s 12-Volt Battery
Ready to bring your EV back to life? Follow these clear, expert-backed steps to jump-start a dead 12-volt battery with confidence.
- Align the Vehicles
Position the EV and the donor car close together, ensuring they don’t touch. This proximity makes connecting the cables easier without straining them. - Secure the Setup
Shift both vehicles into park and engage their parking brakes. This keeps everything stable during the process. - Power Down Completely
Turn off all lights, accessories, and electronics in both cars. This minimizes electrical draw and reduces risks while connecting the cables. - Attach the Positive Cables
Take the red positive (+) jumper cable and connect one end to the positive (+) terminal of the EV’s dead battery. Then, attach the other end to the positive (+) terminal of the donor vehicle’s battery. - Hook Up the Negative Cables
Grab the black negative (–) cable and secure one end to the negative (–) terminal of the donor battery. Next, connect the opposite end to the designated negative grounding point on the EV—not directly to the dead battery’s negative terminal unless specified. - Double-Check Connections
Verify that the cables steer clear of moving parts like fans or belts. Ensure the clamps make solid metal-to-metal contact with the terminals for a reliable charge. - Start the Donor Vehicle
Fire up the gas-powered car with the healthy battery. Let it run for a moment to begin transferring power. - Revive the EV
Now, attempt to start the electric vehicle. If it doesn’t turn over immediately, wait a minute or two before trying again.
Extra Tips for Success
Once the EV starts, let both vehicles run briefly before disconnecting the cables in reverse order—negative first, then positive. If you’re frequently dealing with a dead battery, it might be time to inspect or replace the 12-volt unit. Portable jump-starters are also handy for solo fixes, offering convenience without a second car.
Why This Matters for EV Owners
Understanding how to jump-start an electric car with a dead battery empowers you to handle unexpected hiccups. While the high-voltage pack drives the motor, the 12-volt battery powers essential systems like locks and displays. With these steps, you’re equipped to tackle a common issue without panic, keeping your EV road-ready.
