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Can Car Battery Recharge Itself? Better Charge Your Car Battery Now!


Of course, the main objective of your car battery is to start the engine. But there are other jobs a car battery does carry out, like powering up the lights, stereo, GPS, and other functions. But when it comes to its recharging, you may want to know, can car battery recharge itself?

A quick answer is, No. The battery installed inside your car is not capable of recharging itself. That said, there are different ways you can recharge your battery.

In this post, we have covered all the possibilities, so let’s dive into details.

Why Your Car Battery Can’t Recharge Itself?

A car battery is never made to recharge itself. Instead, it’s there to power up your engine when you turn the key from ignition mode to START. That process alone needs almost 40% of the battery’s stored energy.


However, that time is not far when we’ll be driving cars having a self-recharging battery. That’s possible in the Full Hybrid or Self Charging Hybrid cars. But let’s do that another day.

Now, you must be thinking about how your battery gets recharged. Let’s get to that part.

What Device Charges Your Car Battery?

An alternator is a component that recharges your car battery. It has a similar structure to a generator. However, it’s a bit unique when it comes to giving juice to an automobile battery.

How does Alternator Charge Car Battery?

The belt of the engine drives the alternator. Therefore, you can say that an alternator mechanically works to begin the battery recharging process.

However, the whole process is not mechanical though.

When you drive your car, the alternator is powered by the revolving of the engine’s belt.

The alternator consists of a stator, call it a compartment, in which a rotor revolves inside the coil windings. These coils are responsible for creating electromagnetic energy.

There’s a carbon copper or only carbon brush that touches the two metal rings. When the belt moves, those rings come in touch with the carbon brush, producing an alternating current.

Now, you have to rectify that current and make it a direct or one-way current.

There are diodes attached to an alternator that carry out the rectification job. That way, your car battery receives direct current and gets the juice.

Moreover, your battery needs to get a moderate amount of current. What does that mean?

Neither too high nor too low.

The high amount of current might affect the performance and recharging of the battery. On the other hand, a low amount of current will delay the battery recharging process.

Therefore, all the modern alternators have a regulator that regulates the voltage before it reaches the battery.

That’s how an alternator charges your car battery.

However, you have to keep in mind that the alternator is not going to work if your car is standing idle. It’s necessary to run the engine so that it powers the alternator. As a result, your car battery will get the necessary recharge.

How Long Does it Take to Charge Your Car Battery Through Alternator?

It depends on the performance of your engine, also known as RPM (Revolutions Per Minute.) The more you rev the engine, the more RPM will be produced.


Moreover, it usually takes 30-60 minutes for a car battery to get fully charged. If you want to boost the battery recharging process, drive on a clear road and make the most of your car’s engine.

Now, there’s another method to recharge your battery. This method doesn’t require you to drive your car. Instead, you can stop your car and recharge the car battery.

Car Battery Recharger

You can charge your car’s battery using an automobile battery charger. It’s a simple device having two clamps that connect to the battery terminals.

Unlike alternators, you can park your car in a suitable location, connect the charger to the battery, and wait until it gets enough recharge to cover the long distance.

Moreover, it takes almost 12 hours for a 12V battery charger to fully charge your car battery. In the case of electric cars, it will take only 30 minutes to get 80% charge to their batteries. Amazing, isn’t it?

Check out the Schumacher Fully Automatic Battery Charger.

How to Use a Car Battery Charger?

  • First of all, make sure the charger is powered OFF. It’s one of the basic precautionary steps as it mitigates the risk of electric sparks.
  • Connect the positive clamp of the charger to the positive terminal of the battery. Moreover, the RED color indicates a positive clamp while BLACK indicates a negative clamp.
  • Connect the negative clamp to the negative terminal of the battery.
  • Set the charge rate. It’s recommended to set the charger to the slowest Charge Rate, which is 2 amps. However, there are more settings as well to charge your car battery faster.
  • Turn on the charger.
  • Additionally, set the charging time if your battery charger has this feature.

Now, if your car battery is not recharging, there might be several reasons behind that. Therefore, let’s learn why your battery is not getting recharged.

Reasons Why Car Battery is Not Recharging

Commonly, there are three reasons why your car battery fails to recharge.

Complete Battery Discharge

If you have parked your car for long durations, for several weeks maybe, then the battery might discharge completely. Besides, if you haven’t covered any long distances, the car battery might also experience a complete discharge.

In that case, you might not be able to start your car. Therefore, the alternator can’t help you with that.

Connecting a charger might wake up the battery again. However, it’s better to consult with an automobile battery expert if you are facing a similar issue.

Cold Weather

It’s true that cold weather affects a car battery’s health. In the extreme winter season, the electrochemical process inside the car battery slows down. That impedes the performance of the battery, and eventually, it gets completely discharged without getting a chance to recharge from the alternator.

Therefore, you have to keep a car battery charger with you, especially if you are living in cold temperatures.

Faulty Alternator

Since an alternator works on electromechanical principles, it might face random issues, just like your car’s engine. Although it’s rare that an alternator goes faulty, you have to keep checking that component of your car.

Unfortunately, there’s no indication your car displays on the dashboard when an alternator stops recharging the battery. That means when you are driving, you won’t be able to notice that the battery is about to reach the drained state.

Therefore, the only way left to recharge your battery is to connect the car battery charger and wait until it gets enough juice to hit the road.

Besides, let the mechanic check the situation of the alternator. Most of the time, you might have to replace that with a new one.

Have a look at the Premier Gear Professional Grade Alternator for your car.

How to Jump-Start a Car?

This method is used when the car battery dies. The external battery charger is not going to help.


Therefore, follow these steps to jump-start a car:

  • Turn off both cars.
  • Take the red (positive) end of the jumper cable and connect it to the positive head of the dead battery.
  • Connect the other red (positive) end of the jumper cable and connect it to the positive terminal of the working battery.
  • Now, connect the black (negative) cable head to the negative end of the working battery.
  • Connect the other black (negative) cable head to a clean metallic surface under the hood of the car of the dead battery. Don’t connect the negative head to the negative terminal of the dead battery. It might cause a spark and explode.
  • Start the car, which has a working battery.
  • Rev the engine for about 2-3 minutes before starting the dead battery.
  • Follow the reverse order while removing the cables.
  • Start the dead battery. Keep the car’s engine running so that it can have enough recharge.

How to Keep Car Battery in Good Health?

Your car battery can pass 3-5 years without misbehaving. However, if you don’t focus on the following factors, you might have to replace your car battery in a year or two.

Proper Maintenance

The routine car battery checkups are not ordinary. They keep the battery of your car in good health. Therefore, always visit the automobile service station for battery checkups.

You can maintain your car battery as it’s a DIY project.

Just clean the grime and dirt stuck on the terminals of the battery for a proper flow of current.

Turn Off Lights

After parking your car, make sure you have turned off the lights. These lights look small, but they drain the battery pretty quick, especially when you leave them on all night after turning off the engine.

Long Trips

Cover long distances and let the alternator give a maximum recharge to your car battery. When your car covers shorter distances, it doesn’t get enough recharge due to slow and lower RPMs.

Therefore, schedule at least two long trips in a week to keep your car battery in good health.


Final Thoughts

As you have seen, you can only recharge your car battery through an alternator or an external battery charger. However, if the battery has completely run out of juice, you have to start your car using the jump-start technique.

You also have to bring your car to the service station for monthly checkups. They will inspect your overall car condition, including the battery.

If the battery of your car is almost completing its age, they will recommend replacing it so that you can enjoy your driving experience without facing any difficult situations.

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