Informational Guide

How Long Does It Take To Charge A Car Battery?

Do you want to know how to charge your car battery and how long this process takes? Let’s take a closer look!

Caring for your car battery is essential if you want reliable transportation. Otherwise, you could head outside for your daily commute only to find a dead battery holding you back. To protect your automotive battery and ensure proper battery care, you want to know how to charge it and how long this process takes. So, how long does it take to charge a car battery? Let’s take a closer look.

How long does a car battery take to charge? Before you look at timing, you must understand the basics of the vehicle’s charging system. The automotive charging system is responsible for keeping your car battery running at optimal levels. Your car charging system involves an alternator, which is just like a generator.

However, the alternator only charges the battery as the vehicle runs. Otherwise, you need an external car battery maintainer to keep the levels topped off. If the battery is completely dead, you will require a golf cart battery charger instead.

Factors that May Affect Car Battery Charging Time

Charger Type

The type of charger makes a big difference from linear to multi-stage and trickle chargers. If you use a quick charger, you might only be looking at an hour or so. But, how long to trickle charge a car battery? The trickle charger is meant to provide a small amount of charge over time and maintain the battery, leaving you waiting several days for a full battery.

Car Battery Type

You can’t use just any charger with your battery. Instead, you should pick one that is compatible with your battery type, thereby affecting the charging time. For example, your AGM battery might require a different charger than your typical truck battery. Additionally, you may have a golf cart battery charger, but it’s likely you can’t use it on your car battery unless the batteries are the same type.


While you may operate your car battery in varying temperatures, charging needs to be more precise to be effective. Your battery’s charging process is delicate and requires special care.

battery temperature

Extremely cold or hot temperatures will alter charge acceptance, so it’s important that your battery be brought to a respectable temperature before you charge it.

Age & Condition of Car Battery

If the battery is heavily corroded, you want to clean the battery corrosion before charging. While this is something that can be resolved, you can't fix an old battery. If your battery is simply old and worn-out, you might not be able to charge it anymore. However, you might be able to recondition the batteries.

Current/Amps Used

You can purchase battery chargers at a wide range of amperage, from 2 amps through 50 amps and more. The amount of amps used changes how fast the battery is charged, but you don’t ever want to use a charger with more amperage if it’s not compatible with your battery.

Calculating the Time It Takes to Charge a Car Battery

How long it takes to charge a dead 12V car battery from flat?

How long to charge a dead car battery? It depends on the battery type and charger being used. If you are able to get the car running, you could possibly charge it fully within an hour of driving. However, it isn’t always easy to start a car with a completely dead battery.

How long it takes to charge a car battery at 2 amps?

Determining how long to charge a car battery at 2 amps will require that you have some patience. Typically, it takes one to two days to gain a full recharge with a 2-amp charger. With this power, you are only offering a trickle charge, which occurs slowly over time. These are best for maintaining batteries.

How long it takes to charge a car battery at 6 amps?

You can also look at how long to charge a car battery at 6 amps. If the battery holds 48 amps, you can expect the charge to take about eight hours. If you want to perform the charge overnight, this might be a good solution for you.

How long it takes to charge a car battery at 10 amps?

Again, how long to charge a car battery at 10 amps will require you to look at some basic math. If you have a half-discharged battery, you should be able to recharge it with your 10-amp device in just a couple of hours. Expect it to take longer if you are using a larger battery.

How long it takes to charge a car battery at 50 amps?

But, how long to charge a car battery at 50 amps? These are quick chargers, able to get your battery up to capacity in just a few minutes. However, you could also overcharge the battery, which could lead to further damage and performance issues down the road.

How long it takes to trickle charge a car battery?

Trickle charging can take several days to get the battery to a full charge. Trickle chargers rely on 1-2 amps of power, so the process goes much slower. However, you won’t have to worry about overcharging the battery by accident, which makes it an optimal choice for battery storage.

How Long It Take To Charge A Battery While Driving?

If you want to charge your car battery without a charger, you might consider driving instead. Do you know how long to leave a car running to charge a battery? In just an hour of driving, you might be able to supply a full charge to the battery, depending on the condition of the battery and what other accessories are running in the vehicle.

Slow Charging vs. Fast Charging

As you look at how long it takes to charge a car battery, you might wonder if the fastest option is the best. However, most experts agree that it is ideal to slow charge the car battery as fast charging can damage the battery over time. To play it safe, you might prefer to use a battery charger that is 4 amps or less.

People Also Ask (FAQs)

Can I just jump start any car battery that isn’t working?

There are times when jump starting the car battery might not work. In these cases, you’ve likely already seen signs that it is time to replace your car battery.

Should I add water to the battery before or after I charge it?

If you are using a lead-acid battery, you want to add distilled water to the battery after charging. This won’t be possible if you have a sealed battery type. Fill the water until it reaches the bottom of the vent, which should be about ¾ below the top of the battery cell.

At what voltage is a car battery fully discharged?

Based on the resting voltage of the battery, 12.8 to 12.9 volts indicates a fully charged battery, while 12 volts shows that it is flat dead. If you get a reading of 12.4 volts, you know the battery is about half charged.

Do I need to charge a new car battery?

There should be a full charge in your new car battery, but it will be charged any extra that’s required during your drive.

What is a typical self-discharge rate for a car battery?

Batteries discharge on their own, even in perfect conditions. The lead-acid car battery has a discharge rate averaging 1% each day when stored at 68–72 °F. At 50 degrees Fahrenheit, you can expect about a 0.25% discharge rate, while 86 degrees Fahrenheit changes the self-discharge rate to about 1.5% a day.

What are some reasons that batteries fail?

Car batteries fail when the vehicle isn’t driven often or long enough to fully recharge it. The battery can also fail when the temperatures are extreme, either hot or cold. Additionally, batteries just get old over time, with a typical battery lasting about five years.

What can I do to extend the life of a car battery?

Make sure you take long drives and go out often to keep the battery charged. Additionally, you should ensure that everything is turned off in the car when you shut down the ignition. Don’t leave the lights or accessories on. You can also inspect the battery occasionally and clean off any corrosion to ensure a solid charge.

What if my battery is dead and I don’t have money to replace it?

There aren’t many options if you can’t replace your battery. You can buy a used or refurbished battery at a local shop, but you might end up with just as many problems. Some auto parts stores will offer you a loaner battery while they put yours on a charger, which might also afford you a couple of days. Plus, the professional charge might be enough to put some life back into your battery.


Now that you know how long to charge a car battery, it's time to put your knowledge to work. Properly charge your car battery and take care of it, so you are never left stranded again.