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How Long To Charge A Dead Car Battery

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If you have ever tried to start your car, only to discover the battery is dead, you know how frustrating that can be. You may wonder how long it will be until your car battery can get your car running again. We did some research, and this is what we found out. 

It will take a minimum of 4 hours, and up to 24 hours to recharge a dead battery. The charging time depends on the power of the charger and the size of the battery.

In this post, we'll share some tips on how to charge your battery properly and what to do if it dies altogether. If you've never dealt with a dead car battery before, this article will help you. Keep reading for more information.

Close up Charging car battery with electricity trough jumper cables. Car repair concept - How Long To Charge A Dead Car Battery

What To Do If Your Car Battery Dies

The engine just wont start. Cropped shot of a young woman calling roadside assistance after breaking down.

If the car battery dies, here is some helpful advice:

  • Call a tow truck that will take your car to a nearby service station. This is usually the most expensive option. 
  • Try to jump-start your car with jumper cables. If you have jumper cables and another working vehicle, you can connect the two batteries and jump-start your car.
  • Buy a new battery and install it yourself. This is a cheap option, but it requires some knowledge of car batteries and how to install them. 
  • Use proper charging equipment to charge your battery. It is an option we will talk about in more detail in the following paragraphs. This will require knowledge of car batteries. 

Signs That Your Car Battery Needs Charging

If you find yourself in any of these situations, then you will need to charge your car battery:

1. The battery warning light on your dashboard is on.

If the battery symbol lights up on your dashboard, there’s probably an issue with one, or all of your car's alternator, electrical system or battery. Low batteries usually cause the battery warning light to pop up. 

2. Your car engine struggles to start.

If you notice that your car's engine is taking longer to start than usual, or if it's losing power while you're driving, your battery might be on its last legs.

3. Your car electrics won't function.

Once your car's electric system becomes slow to respond, your battery might be drained.

4. Your battery is over five years old.

The average car battery lasts between two and five years. But, if you're someone who regularly uses their car for long periods without starting it, or if you live in a hot climate, the car battery might not last as long.

How To Charge a Dead Car Battery Using a Battery Charger

Close up Charging car battery with electricity trough jumper cables. Car repair concept.

Things To Consider When Charging Your Car Battery

If you think your battery might need charging, here are a few things to keep in mind:

  • The larger the battery, the longer it will take to charge.
  • A standard charger will take longer to charge a battery than a quick charger.
  • Batteries charge faster in warm weather than in cold weather.
  • A new battery will charge faster than an old, worn-out battery.

How To Remove A Dead Car Battery

Before charging your battery, you need to first remove it from your car. Here are the steps:

  1. Turn the engine off and disconnect the cables.
  2. Locate the battery. They're usually bolted under the hood. If you're not sure where it is, check your car's manual or contact a mechanic.
  3. Once you see the battery, you need to locate the positive and negative terminals. If your battery has caps covering the terminal, remove them first. 
  4. Disconnect the battery cables. During this step, you need to be very careful. We recommend you use protective gear such as eye protection, especially when working around batteries. 
  5. First, disconnect the negative battery cable. Push it far out of the way and you can now remove the positive cable. Never let the wrench touch both the negative and positive terminals at the same time. Even if your battery is dead, there might still be some residual electricity that can create a spark. 
  6. Remove the battery hold-down clamp using a socket wrench. You can find the clamp that locks the battery to the tray that it sits on. 
  7. Finally, carefully lift the battery up. 

How To Charge A Battery Using A Battery Charger

After removing the battery from your car, here are the steps you should follow:

  1. Prepare the needed equipment and material. Ensure that the charging space is clean, tidy and well-ventilated. 
  2. Leave your charger unplugged for now. 
  3. Depending on your battery type, set the proper charge setting.
  4. Locate the positive and negative sides of the battery. Clip the red cable to the positive side. Then, on the negative terminal side, attach the black cable. 
  5. Connect your charger to the power source then wait for the battery to charge completely.

How Long Does It Take To Charge A Car Battery?

The time it takes for a car battery to charge depends on the power and size of the battery. The following list shows the time needed to charge a standard car battery:

  • 2 Amp Charger: 24 to 48 hours
  • 4 Amp Charger: 12 to 24 hours
  • 10 Amp Charger: 3 to 6 hours
  • 20 Amp Charger: 2 to 4 hours
  • 40 Amp Charger: 30 minutes to 1 Hour

What Is The Best Speed To Charge A Car Battery?

Fast charging a car battery can make its life shorter. On the other hand, long-charging with low amps can keep the battery's lifetime long. 

How To Reinstall Car Battery?

When replacing or reinstalling your car battery, all you have to do is reverse the process you used to remove the battery with the following things in mind:

  1. After charging and reinstalling, ensure that the battery terminals are clean. 
  2. Ensure the fasteners on the bracket are secure, so the battery will not vibrate or move around when driving. 
  3. When reconnecting the battery, always secure the positive terminal before the negative terminal. Doing this will prevent the electrical circuit from being completed before everything is connected. 
  4. Close the hood and start your engine. 

How To Jumpstart A Car Battery

The booster cables and discharged battery, cold winter day

The process is relatively quick and easy, and you can do it with a few simple tools.

  1. Make sure that the positions of the cars are correct - park the working car in front of the disabled vehicle, with the hoods open.
  2. Connect the jumper cables to the battery terminals, making sure that the red (positive) line is attached to the red (positive) terminal on the working battery and that the black (negative) cable is attached to the black (negative) terminal on the disabled battery.
  3. Once the cables are in place, start the working car and let it run for a few minutes before trying to create the disabled vehicle.

Check out this NOCO Jump Starter Kit on Amazon

If everything goes according to plan, your car should start right up. Just be sure to disconnect the jumper cables before driving off!

How To Pick The Right Car Battery Charger?

Smart male customer buying car battery n the car supermarket

With all the different types and models on the market, it's tough to know which one to choose. Here are a few things to keep in mind when picking out a charger:

First, consider the type of battery you have. Lead-acid batteries are the most common, but there are also chargers designed for lithium-ion batteries. Make sure you get the correct charger for your battery type.

Second, think about the size of the battery. You charge a small battery with a standard charger. But, you'll need a heavy-duty charger that can handle the increased load if you have a larger battery.

Third, consider how often you'll need to use the charger. If you only need it occasionally, a basic charger will suffice. But if you need to use it frequently, look for a charger that includes features like automatic shut-off to prevent overcharging.

If you're someone who is always on the road, consider investing in a portable battery charger. 

Check Out this NOCO GENIUS% Portable Battery Charger on Amazon

By keeping these things in mind, you will pick a suitable car battery charger for your needs.

Frequently Asked Questions

Do You Need To Charge A New Car Battery? 

Maintenance of the machine. A male car mechanic takes out a battery from under the hood of a auto to repair, charge or replace it.

There is a common misconception that you always need to charge a new car battery before using it. While there are some instances when it is important to charge your battery fully, this is usually not the case for brand new batteries.

They will already have some charge built up when you get them. For example, if you just bought a car and brought it home without plugging it in overnight, don't worry – the car's battery should be more than ready to go. 

Final Thoughts

It's always best to be prepared for this kind of situation. So when your car battery dies, you'll know what to do. Also, if you feel like it, you can always bring along a spare car battery or jumpstarting kit. Because you'll never know when your car battery will die.  

Since you're already here, you might also want to read:

What Size Are Battery Bolts?

Can You Jump Start A Truck With A Car?