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How Long to Charge a Car Battery at 6 Amps? – Average Charing Time

Written by Edwin Jones / Fact checked by Andrew Wright

how long to charge a car battery at 6 amps

Every car has a battery that can drain after an extended period of usage. You may need to charge it to start your automobile in this situation. It’s a bit of a hassle, right?

So, how long to charge a car battery at 6 amps?

A medium-sized battery will typically take ten to twelve hours to charge. However, depending on the charger and other factors affecting its charging period, it may take a bit longer.

How Long to Charge a Car Battery with a 6 Amp Charger?

It’s difficult to say how long it takes to charge a battery with a 12 volt charger at 6 amps. However, there is a method for you to determine the estimated charging time.

In detail, divide the battery’s Ah (Amp Hour) rating by the charger rating. For example, with a 50 Ah battery and a 6 amp charger, you will get 8.3 hours.

You should also add roughly 10% to that total number, since electronics aren’t 100% efficient. Therefore, you may expect 9 to 10 hours of powering the battery.

However, as I previously stated, some factors may affect this estimate, causing the time calculator result to change.

Before we jump into those factors, let’s have a quick review of the most common devices used to charge a 12 volt battery.

Types of Charger


  • Simple Charger

A simple charger is a basic unit that provides continuous DC or pulsed DC power to the battery. It has a minimal design and is reasonably priced.

However, this type of recharger has a slow work rate. Thus, it may take a long time to power your battery.

  • Smart Charger

A smart charger is one that has advanced functions, such as sulfate buildup removal, overcharging prevention, and cold weather protection.

  • Pulse Charger

A pulse charger is a type of device that sends a series of electrical pulses to the battery. It dissolves lead-sulfate crystals in lead-acid batteries, which can help the battery last longer.

  • Solar Charger

As its name implies, a solar charger uses solar energy to power a battery. You can find products of this type with trickle charging features. It often works not only on cars but boats and motorcycles as well.

  • Trickle Charger

This is a type of maintainer charger that can be left in a car to power the battery for a week or more. For a trickle charger to charge a battery, it will generate 1 to 3 amps.

While linked to your car’s power source, it can also prevent self-discharge and overcharging. Moreover, since it uses low voltage, connecting this device to the battery installed in the car will not harm it.

Factors That Will Determine How Long It Takes to Charge a Battery


  • Battery Size. Typically, the larger the battery, the longer it will take to charge.
  • Battery Charge Status. It takes longer to charge if you start with a drained battery instead of one that’s partially filled.
  • Environment Temperature. Typically, it takes longer to charge in cold weather compared to hot weather.
  • Charger Amp Capacity. The amp rating is a major factor in determining charging time. In general, the higher the amp rating of your charger, the faster your battery will charge.

How to Connect the Charger to the Battery

Charging a car battery with a trickle charger or other device is straightforward, and you don’t have to remove the battery itself. Still, there is a proper way of attaching the charger to the battery.

First, connect the charger’s red clamp to the battery’s positive terminal. Then, attach the black or negative clamp to the car’s solid unpainted metal.

It’s also a good idea to keep the metal section where you attached the black clamp away from the battery; this will prevent any hydrogen gas that gets released from sparking and causing an accident.

After that, plug the charger into an electrical outlet, and you’re done.

Some devices, such as smart chargers, may require you to follow additional instructions, such as selecting the proper mode to begin charging.



What if My Battery Won’t Charge?

When your battery fails to charge, it is usually due to corrosion, an issue with the alternator, or a problem with the battery itself.

How to Troubleshoot a Battery Issue and Replace?

If you experience your battery becoming faulty, here are some troubleshooting guides that will help determine if your battery needs replacement.

  • Check the battery connection for a loose or corroded cable, terminal, or other connectors. Secure the loose parts and remove the rust.
  • Look for parasitic drain devices such as GPS and other gadgets that are not properly shut down or unplugged. This may be why your car constantly lacks power.
  • Check the water level if you are utilizing a maintainable battery.
  • Full charge your battery at 8 amps or any other amperage you see fit, and test the battery using a multimeter to see if it is still functioning properly. You should see a 6V rating with the engine off.

Is it Better to Charge a Car Battery at 2 Amps or 6 Amps?

Practically speaking, the higher the amps of the battery charger, the less charge time it may require.

In this instance, charging a battery at 6 amps will be quicker. So, if you’re too impatient to charge a 12V battery at 2 amps, consider upgrading.

For more time to charge a car battery at 2 amps, please take a look at this article.

How Many Amps Should I Charge My Car Battery at?

In general, a 20 amp to 40 amps rating or higher is considered fast, whereas anything less than 10 amps is considered slow charging. So if you are wondering about how long to charge a car battery at 10 amps, check it out here!

That said, powering your car battery at 50 amps or higher may result in overcharging and shortening of its lifespan, especially if you’re not using a smart charger.

In general, you should go with 4 amps to 7.5 amps to be safe.


You should now know how long to charge a car battery at 6 amps and the factors affecting the charging time.

Regardless of which charger you use, preventing your car battery from draining is always a wise option. Turning your car on for at least 15 to 20 minutes a week may also help maintain its power source.

Furthermore, when purchasing a battery replacement, always ensure that the model you choose is adequate for your vehicle’s specifications.

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