How To Charge A Battery At Home?

Much like the law of gravity, every battery that discharges must be recharged to become usable again. We live in a digital era that has done away with single-use battery systems. Today, even the 1.5-Volt AA cells you buy for remote controls can be recharged using appropriate systems.

However, things can get complicated when it comes to higher voltage systems. You don’t want to instill guesswork with batteries that can electrocute you. That’s why it takes more consideration, with most individuals simply giving up and calling their local battery repair shop in favor of professional services. If you want to remain separate from that crowd, here is a detailed guide on how to charge your battery at home.

How To Charge Battery at Home?

Before you decide on following through with the process, it helps to ensure that you have all the required equipment. Therefore, you need to tally the below-mentioned list to determine whether you can charge the battery in question.

  • Safety apparel, including gloves, terminal covers, and insulated glasses. They protect you in case there is electrolyte leakage or sparks flying from metal surfaces.
  • A multimeter measures the voltage and current through the battery and the charging circuit.
  • A suitable battery charger that yields enough energy for charging the battery. There are a few mentioned later in this guide.
  • Charging cables connected to a robust power source. Although your battery charger might have those, there is no harm in having a couple of spares to extend the length or when the original ones are damaged.

See full this video: How To Charge Battery At Home

Charging the Battery

In order to charge the battery, you need to follow the below-mentioned steps.

  1. Isolate the battery from all circuits. If you’re charging a vehicle battery, you need to switch off the car/motorbike and disconnect it from the terminals. Remove the negative terminal first, followed by disconnecting the positive terminal.
  2. Measure the voltage drop across both terminals using a multimeter. Set the reading to 20V and use the connectors to check the voltage. You should only charge the battery once it drops to less than 75% of the rated voltage.
  3. Turn off the charger and connect its cables to the battery terminals. If it has a digital interface, make sure only to let the charging start once you set the voltage and current as per the battery’s ratings.
  4. Turn on the charger and wait for the battery to charge. It usually takes around one hour to charge a 12-Volt battery. You can check the charging status by connecting the multimeter to the battery terminals.
  5. Once the battery is charged, turn the charger off and disconnect the terminals carefully. You can now reinstall the battery to its required circuit and use it for its intended purpose.

What Is the Best Method To Use When Charging a Battery?

You can charge a battery by using the following methods.

  • Using a charger specifically designed to charge the battery.
  • Jump starts using another fully-charged battery to restore a discharged one.
  • Retrofitting another charger to charge the battery.

Usually, it’s best to go with a charging system, preferably a trickle charger, to charge a car battery. It has an appreciable charging speed, and you can adjust it according to your needs.

Moreover, a trickle charger makes the charging process safer than other means. You can rest easy in the fact that it won’t overcharge the battery or overheat the terminals. It helps you maximize the lifespan of your battery so that you can use it way past the warranty period.

How To Charge Your Car Battery At Home With a Laptop Charger?

How To Charge Your Car Battery At Home With a Laptop Charger?

If you don’t have the requisite charger at home, you can make do with a laptop charger to charge a car battery. It involves the steps mentioned below.

Step 1: Make Sure the Charger Is Suitable for the Job

You can use a multimeter to ensure the laptop charger provides the required energy. Connect the positive end of the multimeter inside the charging tip and the negative end at the outer end. Turn on both the charger and the multimeter. The voltage must read at least 13 Volts, and the current should remain above 3.5 Amperes.

Step 2: Disconnect the battery

Once you’ve ensured that the charger suits your needs, you need to disconnect the battery from all active circuits. First, disconnect the negative terminal using a screwdriver or wrench, followed by the same with the positive terminal. Keep it in a safe, well-lit area for charging, where you know no children or pets are roaming about.

Step 3: Retrofit the Charger

Next, you need to modify your laptop charger to make it compatible with the car battery. For that, you need to cut off the charging tip and expose the wires underneath it. Typically, there are three sets of cables, with the innermost one being positive and the outermost one being negative.

It helps to leave the intermediate ground cable insulated. Before connecting it to the battery, it is best to briefly turn on the charger and check with the multimeter that it’s still providing enough voltage. If not, you may have entangled the wires and need to start the process again.

Step 4: Charge the Battery

Now, all you need to do is connect the cables and charge the battery. Secure the terminals and draw them to the appropriate wires of the charger. Turn on the charger and observe it for a few minutes. If there are no sparks or burning smell you can detect, it means the charger is compatible with the battery. You can safely leave it for a while and check the battery charge with the multimeter every 30 minutes.

Step 5: Remove the Charger

Once the battery receives enough charge, you can turn off the charger and disconnect it from the battery. In all probability, you can’t use it to charge a laptop again. So, it helps to get another compatible charger for the same.

See full this video: How To Charge Your Car Battery At Home With Laptop Charger

How Long Does It Take To Charge a Battery at Home?

It depends upon the method used to charge the battery. A trickle charger or battery maintainer can take up to 4 hours to charge a battery to its full capacity. A fast charger can reduce that to about 20 minutes. If you retrofit a laptop charger, it can take anywhere from 1 to 3 hours to fully charge a 12-Volt battery.

How To Charge a Battery With a Battery Charger?

Most chargers come with instructions on how to use them to charge a battery. Generally, it’s a pretty straightforward process.

  1. Turn off the circuit and disconnect your battery from it.
  2. Use the provided cables to connect the charger to the battery. In case there is a ground cable, you should attach it to a metal pole or your car’s hood.
  3. Turn on the charger to charge the battery. You may need to adjust the settings if it can configure charging parameters, like the voltage and current supply.
  4. Check the battery charging status after some time using a multimeter. When it’s fully charged, turn off the charger and disconnect the cables. Your battery is now ready for its intended use.

Top 3 Car Battery Chargers

Hundreds of battery chargers are designed for various applications, so you should research which one suits you best. Fortunately, here is a collection of our picks for the best chargers per the application.

NOCO Boost Plus GB40 Jump Starter Box

A multi-function tool that you can use for various devices, the NOCO Boost Plus GB40 jump starter box is a must-have for every household. You can use it to recharge laptops, smartphones, car batteries, laptop batteries, and most other devices that run on lithium-ion batteries. It’s water and dust resistant, with a portable design that lets you conveniently carry it in a purse or backpack.

NOCO GENIUS1 Portable Car Battery Charger

If you want a tiny trickle charger to charge a car, truck, or marine battery, then NOCO GENIUS1 is your charger of choice. Its variable settings ensure maximum lifespan for your battery of choice. With a price tag of just under $30, you can easily stash it within a dashboard or sleeve pocket, ready to go when you have a discharged battery.

Schumacher SC1280 Automatic Battery Charger and Maintainer

In case you don’t wish to mess around with the settings, the Schumacher SC1280 is a trickle charger that automatically configures it as per the battery specifications. It’s a bit costly, but you can charge batteries for motorcycles, boats, cars, and trucks with just a plug-and-charge process. You can even use it to revive dead batteries.

Frequently Asked Questions

Can You Charge a Dead Battery With a Battery Charger?

It depends on whether your charger supports the configuration. You don’t want to supply too much current to dead batteries as it can cause an electrical fire. In most situations, trickle chargers and battery maintainers are ideal for reviving dead batteries.

Can I Charge Any Battery With a Battery Charger?

No. You must go through the owner’s manual or the instructions on the pack before charging the battery.

Can I Charge the Car Battery Using a Laptop Charger?

Yes, but only if it has ample current and voltage supply. Excessive energy can cause overloading, whereas the battery won’t charge without adequate energy.

Can a 19V Charger Charge a 12V Battery?

Yes, but it should have a suitable current supply.

Can I Charge My Car Battery With a 12-Volt Charger?

Usually, a 12-Volt charger loses some of its voltage to the connecting cables. So, it’s best to use at least a 13-Volt charger.

Can We Charge a 12V Battery With a Laptop Charger?

Yes, if the laptop charger can supply at least 13V and 3.5 A.


Keeping your car battery fully charged ensures that the electrical systems perform as per your requirements. We hope this guide on how to charge a battery at home provided you with the necessary information to improvise when needed. Still, it pays to have a dedicated charger when you don’t.






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