How to Charge a Car Battery without a Charger

charge car battery without charger

It’s not every day you charge car battery without a charger. You might not have access to a charger or your kid broke the charger. But relax, this can happen to anyone. 

That’s why it’s always better to know the proper way to do this. In this well-crafted piece of article, we’ll show a detailed guide on how to charge a car battery without a charger. 

After going through the article, we’re sure you’ll know the ins and outs of charging a car battery without a charger.

Without further delay, let’s hop on the wagon and start the guide-

How to Charge a Car Battery without a Charger: 6 Steps

As we all know car batteries constantly charge themselves while they’re attached to a vehicle. But turns out, people use this tool for other purposes too. 

And this goes without saying that no one uses it for purposes while it’s plugged into the vehicle. So, that brings us to our main point of this article; how to charge a car battery without a charger or jumper cables.

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Here are the 6 easy steps we prepared in detail for your convenience-

Step 0: Make sure you have these Items

Before we dive into the actual process, here’s a note for you. Whenever you’re working with electrical components, safety should be the first and foremost concern. 

For protecting yourself from the considerable voltage and current of the battery, grab these things first-

  • Safety glasses
  • Protective gloves
  • Wire probes and clips
  • 3 pieces of holiday lights

These essentials will keep you safe from any kind of accident that may occur during the process. We know the holiday lights might seem weird at this point. But bear with us for a while. 

Step 1: Select a Power Supply

First things first, you need to select a power supply to charge the battery. Now, this can be anything powerful enough to charge a battery. 

Although our suggestion would be to go for an AC power supply. An AC power supply is always reliable unless the wiring has some serious problems. But the chances of that happening are slim. 

However, you might not have access to that. So, another battery can do the job too. But make sure that the other battery has enough juice to lend some. 

Step 2: Figure Out the Power Output

How to charge a car battery at home without a charger? Even the question seems unconventional, right? That’s why in such situations, it’s always better to charge at a slower rate than usual. 

This trickle effect will make sure there is no overcharging, fume, or explosion(don’t get scared, it won’t explode) during the process.  

Nonetheless, the ideal thing to do here is to monitor the charging session. You can figure out the power output with the wire probes you got. 

Now, note down the voltage and current of the power output. Then, with the same probes, check the voltage of the car battery. By comparing these two data, you’ll have an idea of how long it’ll take to charge the battery.

Step 3: Connect the Lights

Before you connect the lights, you need to make some adjustments to the placement. The safest way to approach is by placing the car battery and power source as distant as possible. 

Although don’t take it too literally. What we mean is to maintain a safe distance for avoiding any spark or other accidents.

With that out of the way, you should be able to connect the holiday lights with the power source and the car battery. You see the lights will work as an indicator. 

If the lights turn on, you know there’s electricity flowing through the wires. Other than that, it trickles into electricity. 

So, even if the current is intense, the lights will shimmer it down. As a result, your car battery will have a safe and sound charging experience. 

Step 4: Attach the Clips

Now that everything’s ready to go, you can attach the clips. As this will let the flow through the lights and the car battery, it’s better to do it in an area where there aren’t too many people. 

Keeping that in mind, attach the negative clip to the power output first. Then, attach the other negative clip to the car battery for completing the circuit. 

The process is the same for the positive clips. After you’ve done, electricity should be flowing through. 

Step 5: Observe the Process

As you already know you’ll be trickling the electricity. So, after a 15 to 20-minute charge, the battery will only get a few volts of juice. You can use a multimeter to check the progress if you want. 

However, you should keep an eye on the lights. Ideally, they should light up with a little amount of heat. 

If it seems that the lights are too hot or bright, that’s your cue to know that there’s too much power flowing through. 

In such cases, you should immediately disconnect. Then, troubleshoot to find out the reason behind this. 

Step 6: Cut Off the Power

You should cut off the power after a period of 30 minutes or so. Start with the negative clips and then move on to the positive clips. 

Now, use a multimeter to check the voltage of the car battery. With only 30 minutes, the chances are slim that it’ll have a full charge. And that’s completely okay. 

You see, overcharging can lead to deterioration of the battery’s health. So, it’s better for both you and your battery not to charge it for a long time. 


Can a completely dead battery be recharged?

If the battery circuits are okay, then yes, you can recharge a dead battery. That being said, you should invest in a good quality trickle charger. It’ll make sure that your battery is never dead.

How long does it take to fully charge a dead car battery?

A dead car battery could take something between 4 to 24 hours for a full charge. Although it can vary depending on the amperage and size of the battery. Suppose, your charger is a 4 amp one and you have a 52Ah dead battery. It’ll take 10 hours to be fully charged.

Can you charge a battery while still in the car?

If you know the ins and outs of your car battery, it’s not a problem if you charge your battery while it’s in the car. It’s completely safe so don’t worry at all.

Will AutoZone charge my battery?

Other than a free battery health check, AutoZone offers free battery charges. The best part is, it takes only about 30 minutes or so.

Can you charge a car battery with a wall outlet?

You can’t connect wires directly to your battery. Batteries and wall outlets require different voltages. So, you’ll need a charger or a few circuits.

Final Word

So, that’s a wrap on our take on how to charge a car battery without a charger. Even though you can charge your car battery without a charger, it’s better if you don’t do it. 

It’s always better to use the dedicated. It’s there for a reason, right? Anyhow, let us know if you’ve any issues you can’t fix. We’ll see what we can do for you. Good luck!

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How to Jumpstart an Automatic Car without Another Car