How To Charge a Car Battery With Another Car

This page will outline the basic steps required in charging your car battery. I will also provide resources for preventative measures to never get stuck in this situation ever again. This includes a cool new piece of technology that will boost your car battery without even lifting the hood. See below for more information on that.

In the mean time, I will assume you found this page because you are currently stuck, and have no way to get to a store for fancy chargers and supplies. So let’s get right to it:

You will need a basic set of jumper cables. If you don’t have any, you will need to flag someone down who has them, or call someone you know.

If you have access to jumper cables, then we can begin:

Charging A Car Battery (step by step):

Step 1: Pull the “helping” car up to your dead car as close as possible. Check where the batteries are located on each car, and try to get them as lined up as you can.

Step 2: Make sure both vehicles are turned off including all interior lights and so on.

Step 3: Inspect the dead battery for damage. If it is cracked or leaking, do not attempt to charge it. You will need a new battery. It is too dangerous to charge a severely damaged car battery.

Locate the positive and Negative terminals on both car batteries. Usually indicated by (+) for positive and (-) for negative.

Step 4: Clamp one of the positive (red or orange) jumper cable clamps to the positive post of the dead car battery first. Then the other positive jumper cable clamp to the positive post of the “helper” car. Then clamp the negative (black) clamp to the negative post of the “helper” car battery. You will have one negative jumper cable clamp remaining. Do not hook that up to the negative battery post of the dead car. Instead, you will clamp it to something metal and non-painted on the dead car. Usually somewhere on the frame, or the engine block (unless your car’s manual says otherwise). Do not be alarmed if there is a small spark upon completing this circuit.

Step 5: Start the “helper” car. Let it run for a minute or 2 at least. Try starting your dead car. If it works, you can unhook in reverse order from above, and you are done. If not, then wait another couple minutes and try again. Sometimes, it may take several tries and a lot of patience. If it becomes clear that it is simply not working after many many attempts, then it may be time for a new battery.

Charging a Car Battery Video Demonstration

A great visual on how to charge a dead car battery.

Jumper Cables

If you don’t have a set of jumper cables, you need to get them. You can find our list of the best jumper cables here, or at a local hardware store. Don’t rely on someone else to have them. Even if you have a portable car battery charger, it could malfunction. Get these ASAP!!

Preventative Measures

Keeping Your Battery Charged

There are a few things you can do to avoid being in a “dead car battery” situation. Check for battery drain with multimeter to be sure the battery is still good. And then follow these suggestions…

• Never leave any lights on, and never leave the key in the ignition in the ‘on’ position.
• Always plug in your car overnight in the winter.
• Don’t leave the car off for too long of stretches of time in the winter. Even if the car is plugged in, and even if I don’t need to go anywhere, I make sure to go out and run the car for a few minutes, at least once every day.
• Nothing is %100. Always keep a charged cell phone, and an emergency kit in your car. If it’s winter, always store things in the trunk or back seat to stay warm, such as blankets, extra clothing, gloves, toques etc.

Portable Car Chargers

No matter how many precautions you take, you can never completely prevent a dead battery even if you’re doing proper car maintenance procedures. Here are some portable chargers you can purchase to make life easier.

I think everyone should have one of these. You never know where you will be when your battery craps out. You may be nowhere near a main road to flag down a helper, or perhaps it’s too risky to ask a stranger for help. I could especially understand the apprehension of the ladies out there wanting to ask for assistance from a stranger.

These chargers come in various forms. Some of them require you to plug them in at home when you are not using them, then take them with you in the trunk, and will work in a portable way. Some of them need to be plugged in while you use them, thus only being useful while you are at home or near a plug-in.

I currently own one that needs to be plugged in while in use. I am looking into getting something more portable. However, the one I have has got me out of my drive-way and garage many times.

One of the best purchases I have ever made!!

This charger plugs into the “cigarette lighter” of your car. It charges your car battery from there in around 10 minutes. You won’t have to worry about hooking up cables, finding a stranger to help you, or anything like that.

They also make a similar charger that is a bit cheaper that plugs into your “cigarette lighter” on one end, and the “cigarette lighter” of a helper car, and you can charge a car battery that way.

It is simply a device where you place a ‘AA’ battery inside and it can connect to your phone and give it a charge. Keep some batteries in your glove compartment or in your emergency kit, and keep one of these with you as well.

A good description of this charger and how to buy it, can be found here.