How to Charge a Car Battery Without a Charger?

How to Charge a Car Battery Without a Charger? Most people search for a way to maintain the battery health of a car when there is no power outlet nearby.

You can use a plug-in maintainer for that, but without a power outlet, it will be difficult to charge. 

In this article, you will see how you can charge the car battery without a charger. Let’s dig into it. 

Car Battery Charger Understanding

The car’s battery dies when you use it and it discharges. Now, the battery will not wholly be empty; the charging level will just be below 12V.

Car batteries usually work around 12.6V. As it loses even 0.1V, its percentage gets lower, and eventually, on 12V or a little less, it dies.

If there is any problem with the car battery, it is better to check the voltage.

As the level is slightly lower than it should be, you can easily fix it. Moreover, using an alternator, the car can self-charge the battery as it moves.

Hence, to fully charge a car battery that is dead but has 12V in it, you can just take it for a long drive. 

Here, you need to make sure that you aren’t using any other components that take the battery’s energy, like lights, radio, etc.

Only half an hour of driving can charge the battery fully to a safe, functional amount. 

However, if it doesn’t fix the problem and other issues arise later, you have to take other steps.

Also, upon checking the voltage, if the level is much lower than it should be, a car battery charger is the only solution to fully charge the battery.

If the car is not even starting, then there is a chance that you have a completely dead battery.

How to Charge a Car Battery with a Charger?

Checking the voltage of the car battery using a multimeter

Caption: Checking the voltage of the car battery using a multimeter

Charging a car battery with a battery charger is quite simple, even if you are on the road. It is because you can find many portable chargers that you can keep with you for difficult times.

However, you should follow the steps to ensure the battery is not damaged or you are not injured along the way.

Here are the steps to charge a battery with the charger.

Prepping the Car Battery Charger

Before charging the battery, the first step that you will take is to remove it from the car.

By removing it, you can get easy access to the components and charge it in a controlled environment before putting it back into the car.

But, some batteries may not be removed due to the design of the vehicle, and thus you have to charge it as it is.

Most removable batteries are in places where you can easily take them out.

However, if they are inside the trunk, under the seat or fender, you might need additional support and tools to remove them.

Types of Car Battery Chargers

Next, you have to decide which battery charger to pick depending on the circumstances that you are facing. Here are the three types of battery chargers that you can use.

  • Charger: Chargers use low-amp charging to recharge the battery, which can take about 24 hours. So, if you are on long trips, a portable charger is for you. It can also overcharge your battery, so keep an eye on it.
  • Maintainer: Maintainers provide continuous power to the battery even when using the lights and speakers of the phone. You can also get solar-powered maintainers to keep the battery full during use.
  • Restorer: Some batteries may face sulfation as they reach low voltages, which can disable the battery power to fully charge and cause problems for the vehicle. The restorers can detect the sulfation problem and use desulfation mode to rejuvenate the battery back to its former health so that it can charge fully.

How to Charge Your Battery?

As you have located the battery (and removed it if necessary), you can follow these simple steps to charge it.

  • Take the charger wire and attach the positive clamp to the positive terminal of the battery.
  • Attach the negative clamp of the charger to the negative terminal of the battery.
  • Set the charger to the lower amp rating and turn it on. Then, set the timer in which the battery can charge completely. 
  • As the timer strikes, check the voltage levels to see whether the battery is fully charged or not. Upon complete charging, you can disconnect the charger.
  • After that, remove the charger from the socket and then remove the charging clamps from the battery terminal the way you attached them.

How to Charge the Battery Without a Charger?

Jumpstarting a vehicle

Caption: Jumpstarting a vehicle

It is not necessary that you always have a battery charger on hand with you.

In such situations, you can use other methods to charge the battery effectively. These methods are as follows. 

Using Jump Leads and a Donor Vehicle

Jumper Cables or jump leads are pairs of cables that have metal clamps on both ends.

These cables can help you charge the vehicle’s battery with the help of another vehicle.

For using jumper cables with the vehicle, you can follow these steps. 

  • Clean the battery terminals and remove any dust and debris. 
  • Put the donor and receiver vehicle in Park or neutral mode while turning the engine off of these vehicles. 
  • With one cable, connect the positive terminal of both vehicles’ batteries. 
  • Use the other cable and attach one end of the negative terminal of the donor battery.   Link the other end to the metal of the second vehicle. 
  • Wait for 5 minutes before starting the receiver vehicle and let it charge. 

Using a Solar charger 

Solar energy is an endless source through which you can charge your vehicle’s battery.

For that, you can use a solar charger that is the size of your battery. However, the charging rate may be slower and can only be done under sunlight.

So, if you don’t mind both of these factors, solar chargers are good to go.

Using a Home UPS inverter

Ups inverters convert the DC power to AC current. You may have found them in homes for charging appliances like laptops or phones when there is a power outage. 

Moreover, you can also use them for charging the car battery as well.

These inverters have safety features to check the battery voltage so that you can prevent overcharging or overheating. 

Putting the battery into Another Vehicle

You can also charge your battery by fixing it into another car, which is an easier method as compared to using jump leads, with no extra components needed.

However, the donor vehicle needs to be using the same battery model as you have so that you can fix it in place. 

If the battery is put into an incompatible car, it can damage the wiring of the car and the battery.  

Using a Portable Car Jump Starter

Portable Jump starter batteries are spare batteries for your car through which you can jumpstart the vehicle.

These packs come in handy when you are in the middle of nowhere and aren’t able to start your car. 

Using these batteries is quite simple. To charge the battery with portable battery packs, you will

  • Place the battery far away from the vehicle and attach the positive clamp to the positive terminal of the vehicle battery.
  • Using negative cables, attach the negative clamp of the charger to the unpainted metal of the vehicle. 
  • Then, turn on the jumpstart battery pack and start the vehicle after 5 minutes of charging. If the vehicle doesn’t start, leave it for a few more minutes and try again. 

Using a Battery Isolator

A battery isolator is another popular option for RV drivers or campers as it helps in transferring the energy from an alternator-charge battery to another flat battery. 

However, you may not use this method if your battery is dead. 


Charging a battery without a battery charger and outlet is easy. You can opt for that either way, using portable battery packs, solar chargers, UPS Inverters, Isolators or other vehicles.

You just need to ensure the battery is in good health before using any of the above methods. 

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