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How Many Amps Is a Car Battery?

How Many Amps Is a Car Battery?

All car batteries have amps and volts. These measure particular characteristics of their electrical performance.

Most of the time, we rate a battery in terms of amp-hours, which is a critical factor when shopping for car batteries.

But shopping for a new battery becomes much more difficult if you don’t know how many amps are supposed to be in a car battery in the first place.

Most batteries have around 48 amp-hours worth of electricity. As far as amps, they usually measure them in cold-cranking amps. A battery’s cold-cranking amps can vary widely. Some of them have up to 500 CCAs. On the other hand, a few batteries might only have 100 CCAs.

In general, newer batteries tend to have more cold-cranking amps. That’s because they’re used to power a lot more electronics. Modern cars tend to have a lot more accessories than other cars.

Usually, you’ll be able to see how many yours has by looking at the label on top of the battery. On this label, you’ll see a variety of characteristics. 

One of them would be its cold-cranking amps.

If you see 550 CCA on the label, that would mean it’s got 550 cold-cranking amps.

You’ll also see the battery’s reserve capacity. This describes how long the battery can discharge electricity without losing power. 

They measure this by discharging the battery at a steady rate and temperature. 

Most of the time, they discharge it at a rate of 25 amps. 

And they do this at a temperature of 80 degrees F.

Also, the reserve capacity of a battery is usually expressed in minutes. So, if your battery has 120 RC, that means it can discharge 25 amps for 120 minutes. 

After that, it won’t have enough power to start the car again.

At the same time, nearly all batteries have 12 volts. That’s how much electrical potential it has.

Because of this, you don’t need to find a specific battery for your vehicle. 

As long as you find one that fits, it should work for your car.

Of course, some vehicles are built to use more powerful batteries than others. Check your owner’s manual to see whether you’ve got to use a special battery or not. 

It’ll contain information about the best battery to use in your vehicle.

What Are Amps In A Car Battery?

Amps describe how fast a battery’s electrons flow through it. 

Amp-hours measure how much electricity your battery stores. It describes how long a battery can discharge a particular number of amps.

It’s easier to describe this using an example. 

Let’s say you’ve got a battery with 200 Ah. That would mean you could discharge 10 amps for 20 hours. Or, you could discharge 5 amps for 40 hours.

You’ll see amp-hours on deep cycle batteries most of the time. However, they’re useful to describe all batteries. 

The more amp-hours your battery has, the longer it’ll last without recharging.

Another way we could describe this is by making an analogy. 

Instead of electrons, let’s think about a river. 

How fast is the water moving down the river? The faster it’s moving, the more water is flowing through at any given point in time.That’s analogous to the amps of a battery.

Volts are a little more difficult to describe, but it’s still relatively straightforward. It’s a measurement of the difference in electrical potential. 

This would be like putting a pump on the river to speed up the flow of its water. The more powerful the pump, the more water will go through it. That’s similar to a battery’s voltage.

Now, each battery is going to have different characteristics. These show up as differences in their voltage and amperage. 

Typically, a car’s battery will have 48 amp-hours. 

That’s not the same as its amperage, though.

How Many Amps Does It Take to Charge a Car Battery

If you’ve ever dealt with a bad battery, you know they can be a pain to recharge. Over time, a battery loses its ability to hold onto a charge. That’s because they’ve got a limited number of cycle lives.

Discharging a battery all the way isn’t supposed to happen. But, if your alternator dies, you might not have much of a choice. 

Then, you’ve got to recharge it before cranking the car again.

A battery charger delivers electricity to your battery at a specific rate of speed. This is also measured in amps. 

Most battery chargers deliver 2 amps worth of electricity. We can divide that into your battery’s amp-hours to figure out how long it’ll take to recharge.

For example, let’s say you’ve got a battery with 50 amp-hours. In that case, it’d take 25 hours to fully recharge the battery using 2 amps. 

Charging the battery slowly tends to be better for its overall performance. 

Other battery chargers might deliver more amps but they could damage the battery.

Overcharging a battery can damage its cells. Eventually, it won’t be able to hold onto a charge at all anymore. 

Undercharging the battery isn’t good, either. Without enough amps, it won’t be able to start the car.

If you’re short on time, you might want to use a battery starter. These deliver a lot more amps at a time than a normal charger. 

Some of them can deliver up to 75 amps. That means a 50 amp-hour battery would take less than an hour to fully charge.

However, charging it that fast isn’t good for the battery.

If you’ve got the time, you should always use a low-amperage charger. These preserve your battery’s cycle life. 

So, it’ll last longer without having to replace it.

Frequently Asked Questions (FAQs)

Most people have a few questions regarding their battery’s performance. So, we’ve put together a few answers to the most common questions people ask.

How Many Amps Are in a 12-volt Car Battery?

Just because a battery has 12 volts, we can’t say how many amps it’s going to have for sure. Most 12-volt batteries contain between 550 and 1000 amps overall.

Is a Car Battery 2 Amp or 10 Amp?

2 amps or 10 amps would describe a battery charger more than likely. Most batteries have several hundred amps. However, chargers tend to deliver electricity at either 2 or 10 amps.

How Many Amps Is a Fully Charged Car Battery?

Each battery has its own performance specifications. Look at your battery’s label to see how many cold-cranking amps it has when it’s fully charged.

How Many Amps Do You Need to Start a Dead Battery?

The larger your vehicle, the more amps it’s going to need. A small car might start with only 150 cold-cranking amps, while a truck might need 500.

How to Measure Your Battery’s Amperage and Voltage

Have you ever wondered whether your battery was charged? If so, you’d probably like to know how you can measure it. 

Using a digital voltmeter is the easier way to do this. You can pick one of them up at your nearest auto parts store.

Simply take the negative diode and put it on the battery’s negative terminal. Then, put the positive diode on the positive terminal. 

Make sure your voltmeter is set to DCA. Then, you should see a rating somewhere between 10 and 14. 

That’s a measurement of its voltage.

A fully discharged battery would still contain about 10 volts. Most of the time, your battery should have 12 or more. 

If it’s got less than that, you might not be able to start your car.

Zach Reed

Hi, I'm the founder of! Having owned a wide variety of vehicles in my life, I was astounded at how hard it can be to find answers to common automotive questions. Rather than sit idly, I decided to create this website to help others!