How to Boost a Car Battery the Right Way

how to boost your car battery

While a dead battery can be frustrating, such a scenario is bound to happen at some point since even the best batteries can only last for so long. Knowing how to boost a car battery can be helpful in keeping you from getting stranded should it die while you’re out on the road.   

While there are ways to make your car battery life last longer, there are also factors that can drain your car battery. The best thing you can do is equip yourself with the proper knowledge in dealing with this emergency. If you want to learn the skill of boosting your car battery, we’ve got you covered. Keep reading to learn more. 

What You’ll Need to Boost Your Car’s Battery

Anyone can experience having a dead battery at some point. When this happens, boosting or jump-starting your car’s battery can get your engine up and running again. Here are the things you need:

  • Jumper cables
  • Donor car (the car with a working battery)
  • Working gloves (optional)
  • Safety goggles (optional)

Note: You don’t need much to perform a battery boost. Yet, finding a jumper cable and a donor car in the middle of an emergency can be difficult. To avoid this inconvenience, it’s best to keep a jumper cable in your trunk at all times.

Safety Tips When Boosting Your Car’s Battery

Although boosting your car’s battery is an easy process, it could be dangerous if you’re not careful. Here are some tips to ensure your safety before starting the boost:

  • Always make sure that you position the vehicles in a way that they don’t come in contact with each other.
  • Inspect the battery and make sure it’s not frozen by looking for cracks on the battery case, bulging, or no sign of liquid when the battery is moved. If you notice any of these signs, you should not perform the boost as it may cause it to explode. 
  • Watch out for large sparks or smoke which could ignite the chemicals in the car battery and may lead to an explosion.
  • Check for battery leakage. Although rare, leaking electrolytes can cause severe burns when coming in contact with the skin, eyes, or even the clothing. 
  • Wear work gloves and safety goggles. 
  • Make sure to turn off all electrical accessories of both vehicles. 

Steps to Boost a Car Battery

Once you’ve established all the necessary precautions, you can now safely start the boost. Follow these steps:

  1. Get the vehicles ready. Turn off the ignition and put both vehicles in park or neutral. Make sure the donor car’s battery has enough voltage to give your dead battery a jolt. 
  1. Position the vehicle close enough for the jumper cable to reach each of the battery’s terminals — but not too close for the vehicles to come in contact with each other. 
  1. Open the hood and locate the battery. If the battery has plastic covers, remove them to expose the terminals. Do not boost if you notice any leaks or cracks on the battery case.
  1. Attach the jumper cables to each terminal in the correct order:
  • Red to Dead – Attach the red clamp to the positive terminal of the dead battery.
  • Red to Donor – Attach the other end of the red clamp to the positive terminal of the donor battery. 
  • Black to Donor – Attach the black clamp to the negative terminal of the donor battery.
  • Black to Dead – Attach the other end of the black clamp to a metal nut or bolt of your car (dead car). Make sure that it is far away from the battery. 
  1. Start the donor car and let it run for a few minutes so it can supply enough power to the dead battery. 
  1. Test the dead battery if it has enough power to start your car (dead car). You can do this by turning on the cabin lights of your car. 
  1. Start the dead car. If you have done everything as instructed, your engine should be up and running again. If it doesn’t start, wait for another 15-20 minutes and try again. 
  1. Once it starts running, you can now carefully unclamp the jumper cables in reverse order:
  • The black clamp on the metal nut or bolt
  • The black clamp from the negative terminal
  • The red clamp from the donor battery
  • The red clamp from the dead battery
  1. Keep your engine running for 20 minutes or more to allow your battery to recharge then drive to a safe location.

Taking Care of Your Battery following a Boost

Avoid immediately disconnecting the jumper cables once the dead car has started. Leave it connected for at least 5 minutes while both engines are running to prevent a power surge. It is also recommended to use the heating and defrosting system of your car for a few minutes to counter the effects of a possible surge.

Frequently Asked Questions

Yes you can. However, it will only be temporary. Boosting a completely dead battery doesn’t mean it will keep working normally.

It depends. If you follow the instructions carefully, it will take you around 5-10 minutes. It may take you longer if your car doesn’t start right away.

The red (positive) cable always goes in first to minimize the likelihood of a short. Also, you should always connect a positive cable to a positive terminal.


Car batteries come with a limited lifespan, which means they may die and require replacement at some point. However, sometimes car batteries flatten out earlier than expected. If you are put in a situation where your car battery dies while you’re on the road, you are already prepared for what to do.

Just follow the steps on how to boost your battery carefully and you’ll be on your way in no time. But in case you are unable to find a donor car in the middle of an emergency, you can always call Neighborhood Roadside Assistance at any time of day and help will be there in 15-35 minutes.