Your car has a lot of parts that you should be familiar with. Understanding the components of your vehicle helps you troubleshoot your car, replace or repair parts on your own, and understand how your engine works together with other devices and equipment in your vehicle.
One of the most important components of any vehicle is the car battery; this component provides power to start the engine as well as supplies electricity to light bulbs, multimedia systems, and other electronic accessories.
Most car owners are aware they have a 12-volt battery, but most don’t realise their battery has amperage ratings associated with it.
To properly charge your battery, you need to know what the amperage rating is. Therefore, in this article, you will learn how to look up your car’s battery amperage.
What Is The Ampere Rating Of A Car Battery?
You can gauge how long a battery will last and how much juice it has by its rating, expressed in ampere-hours. In most cases, batteries rated at 20 ampere-hours will be capable of supplying enough power for an entire day’s worth of usage without recharging.
On average, most car batteries will range from 40 to 65 ampere-hours. The “mAh” rating on a battery provides the total amount of current that can be supplied to a vehicle in one hour. Most car manuals or large cars will list this rating somewhere on or near the battery.
Different types and sizes of batteries exist; however, most small batteries will be rated at 40 ampere-hours, and larger batteries can be rated at 50 ampere-hours, while large trucks and other larger vehicles will have batteries rated around 75 ampere-hours.
Car manufacturers recommend considering the voltage of the battery, its size, and the Cold Cranking ampere rating before purchasing a battery for your vehicle.
What is CCA?
Cold Cranking Amperes, or “CCA,” refers to how much power your car battery has to start the engine when it is cold outside. When referring to the battery’s CCA rating, we are talking about how many amps it can produce for a specific period of time (30 seconds) with a voltage of 12 volts down to 7.2 volts.
If a battery has a higher CCA rating, then it will have more starting power available than a battery with a lower CCA rating. However, in the winter months, the colder temperature will make it more difficult for you to start your vehicle than when it’s warm, since the engine needs more power to crank over.
The typical range of CCA ratings would be from 150 to 500, depending on the size of the battery and how much power it has stored. The CCA rating provides an accurate way to estimate how long a battery will last and how efficiently it will work in cold temperatures.
How Many Amps Does a Car Battery Have?
Most car batteries have an amp rating of 550 to 1,000 amps. The amp rating is how many amps are stored within the battery, indicating how much energy it provides to the vehicle.
Most batteries show their amp rating somewhere on the outside; however, if you can’t find it anywhere, search for your automobile model number on the manufacturer’s website.
Another method for determining the amp rating of your car battery (and your car’s amperage) is by asking a professional mechanic.
The size and type of your automobile also play an important role in determining the type and amp rating of battery required for your automobile.
For example, because compact cars like small cars or compact SUVs do not require as much electricity to operate on a daily basis, they will have smaller-sized batteries that store approximately 400 to 600 amps.
Conversely, larger vehicles like full-sized SUVs, trucks and vans typically require much higher amounts of electricity to operate all of the heavy-duty components and systems that come with these larger vehicles.
Some of the larger vehicles may also have batteries with storage capabilities that exceed a range of 1,000 amps. If you own one of these larger vehicles and it has a smaller-sized battery, consider replacing that battery with one that has a higher amp capacity!
How Many Amps Does a Car Battery Draw While Turned Off?
A battery can use about 400 amps to start a little vehicle and maybe more than a thousand amps on a larger vehicle, so that’s why car makers make their cars’ batteries with much more than needed to start.
You always want your battery’s amperage to be around 00.00, because draining your battery even just .5 will ruin it quickly, with all the reasons batteries fail and get ruined.
When a vehicle’s engine is off, and there is no load on it, the amperage draw, or the draw of current, of the vehicle’s battery goes very low do to what is usually called parasitic drain or quiescent current.
The battery will not have a consistent draw, as it can vary based on many factors such as the make and model of the vehicle, the electrical configuration, and if any aftermarket accessories are added.
In most cases, when a vehicle is off, it has a parasitic drain somewhere between 20 milliamps (mA) to 50 mA.
Keep in mind that some luxury models or very high-electronic vehicles may have a little higher parasitic drain because of more devices requiring constant power.
Factors that can Decrease Battery Capacity
Battery Age: Over time, as a battery gets older, its health declines and the amount of amp hours also declines, which is why older batteries can drain easily.
Battery Temperature: On average, moderate temperatures provide the best performance for batteries. Cold temperatures reduce the battery voltage (capacity), therefore the battery won’t provide enough power to your car’s electrical components during cold or winter months.
How Do You Measure Car Battery Amps?
It’s not as easy as just plugging a car battery into an outlet and charging it as long as you want.
You need to know your car battery’s total capacity and how much charge it has left. You can either use a battery tester or a digital multimeter to get this information. If you’re using a multimeter, you can figure out the voltage of the car battery.
To get the amps, you need to know the battery’s ohm rating. Once you have that, you can use Ohm’s Law (volt = amps x ohms) to calculate the amps by dividing the voltage by the ohm rating of the battery.
In addition to using a tester or a multimeter, you can figure out how much charge is left in a car battery by back-calculating the standard values.
If you want to test the voltage of the battery, you will turn your meter to DC (Direct Current) and connect the red lead to the positive battery post and the black lead to the negative battery post.
| Multimeter Reading (Volt) | Percentage of Charge Remaining |
| 12.6 | 100% |
| 12.4 | 75% |
| 12.2 | 50% |
| 12.0 | 25% |
| 11.9 and below | Dead |
When you know the percentage of charge remaining, you can calculate the current car battery amps. If a 1000-amp battery has 50% capacity, then the current car battery amps is 500.
FAQs.
How many amps are in a 12-volt car battery?
Most of us assume the car battery belongs to the 12 volts category, but not all of us are aware of the ampere rating of our vehicle. An average car battery has a capacity of around 48 amp hours; when fully charged, it delivers 1 amp for 48 hours, two amps for 24 hours, and so on.
Should I charge my car battery at 2 amps or 10 amps?
If you want a faster battery charge rate, go with the 10 amps. Low charging current at 2 amps can be unreliable, but it won’t hurt if you have two chargers.
How many amps is needed to jump-start a car?
That being said, a small to medium-sized car would take around 200-400 amps to start the engine. Similarly, a large-sized automobile would probably need close to 1000 amps. However, a large truck would require about 1500-2000 amps to start.
How many amps is a 12V cigarette lighter?
A car cigarette lighter has a nominal voltage rating of 12 volts but is limited to 10.2 volts with a maximum current of 10 amps. It can efficiently function as an outlet in cars and is used to provide power to a wide range of devices, such as radios, mobile phones, and laptops.
How many amps does a 12 volt car charger put out?
A 12 volt charger can be had from a low milliamp output (100, 200, 500 milliamps), up to 90 amps, that will plug into a 115 volt wall outlet (chargers above about 65 amps usually require a 20 amp circuit, so check).