How Many Watts Are In A Car Battery ? How Many Watt

When we talk about batteries, we get to hear about a lot of terminologies; voltage, ampere, amp-hours, watt, and watt-hour. These terminologies can be a bit confusing to a non-tech-savvy person. Despite this, understanding some of these terms is essential as they help you make the best choice when looking for the ideal battery for your car or any other electrical device. So, what are watt-hours and watts?


Low Temperature Current24V Emergency Starting Power SupplyBattery specification: 25.2V28Ah (lithium battery) , 27V300F (supercapacitor pack) Charging temperature:-40℃~+50℃Discharging temperature: -40℃~+50℃Starting current: 3000A

Watt simply means the amount of power consumed by a device. It is the voltage multiplied by the number of amperes (current/ energy flow). On the other hand, watt-hours is another way of calculating or measuring the capacity of a battery. Therefore, to know how powerful a device is, you look at the watt. In the article below, we answer questions relating to the number of watt-hours a car battery can hold, use, and handle.

You are watching: How many watts are in a car battery

How many watt-hours does a car battery hold?

To answer this question, we first have to get an understanding of terms like amperes and voltage. When we talk about amperes, we refer to how much electricity flows per second (current). If the number of amperes in a battery goes up, then the current flowing through the device per second also goes up. On the other hand, volt our voltage is the amount of energy an electronic circuit gets. Most batteries have a fixed voltage. For example, you can get a 6, 12, 24, or 36 volts battery. Apart from this, most vehicles or devices always require a certain voltage amount. For example, for a device that works on 12v, you will need a battery that supplies 12V.

Most times, when you are selecting a car battery, we look at different factors. One of these is the amp and watt-hours you need. All this always depends on the battery application and your geographical location. For example, when you select a battery to use in UPS, you will have to consider the capacity that will be enough to cover more than two to three times the expected outage. To know this, you will take your average daily use and divide your car battery's voltage to estimate your required amp hours.

So, to answer our question above, we already know that watt-hours are another way to measure the capacity of the battery in your car. To calculate the watt-hours, we multiply the number of amperes with the battery voltage.

For example, a 24V battery with a 50Ah will have a 2400Wh (24 x 100).

How many watts can a car battery handle?

For you to understand and answer this question, it is essential to know your car battery's voltage and amperage amount. The amount of watts your car battery can handle depends on these two key things. To know the number of watts your car battery can handle or holds, here's a simple formula to follow;

Wattage = Amps x Voltage.


A standard car battery is rated at 45 amps per hour. When computed on a scale of 20 hours, it means it can crank out 2.25 amps at an average of 12V during the period. Therefore, the wattage will be 540W. Let's take a look at different examples also;

Suppose you have a car battery that has 24V and draws 30 amps. To know the power consumption of your car you will take 24 x 30 = 720W.

Suppose you happen to have a second different car model in your garage with two gears or speed settings. The car engine runs on 12V and draws 20A when switched to a speed setting of two. The power consumption for this car will be 240W (12 x 20). In case you switch to a speed setting of 4, the car engine still runs on 12V but draws 25A. In this case, the power consumption (wattage) will be 300W (12 x 25).

See more: Samsung Gear Fit 2 Pro Vs Fitbit Vs Samsung Gear Fit 2 Pro Vs Fitbit Charge 2

From the computations above, it is important to understand that this formula works for any car battery. Apart from this, it has also been proven to work universally. Therefore anyone with any model or a different brand of a car battery can easily calculate its wattage with a simple formula.

How many watts does a car use?

When looking at how many watts a car battery can handle, it is also good to consider how many watts your car can use or an average car is supposed to use.

Honestly, the number or amount of watts a car uses depends on the battery type you are using. Mostly all vehicles have different batter sized and specifications. Let's take an example of a vehicle that uses Lead-acid batteries. These batteries come in 2V cells. The most common voltages are 2V, 6V, A2V, and 24V. With lead-acid batteries, the more amps you pull out, the less power consumption you get.

It is good to note that, on average a car battery can maintain about 4 to 5 amperes for about ten hours. I such a case, the battery is equated to a 50amp hour battery or 600-watt hour battery. In today's market, many batteries are rated at a 10-hour rate or 20 hours. These rates mean the number of amperes a battery can sustain for 20 or 10 hours before the voltage drops to a point where it cannot be used again.

Therefore, the amount of watts a car uses varies upon the car and the systems within the car. As every car is different, for you to know the watts yours use, it is best to measure your car.


Now you know what watt is and how wattage computations are done. Apart from this being one of the vital factors to consider when looking for a car battery, there are additional factors you should also keep in mind.

Some of these include:

Selecting the right-sized battery with the right cell power,

A good battery brand that assures you of being safe and highly efficient.

See more: What Phrase Do Muslims Repeat As An Expression Of Shahadah, The Five Pillars Of Islam

Consider the reserve capacity

I hope that from this information you will be able to make a well-informed decision will selecting the battery that suits your needs.

Related Articles

Leave a Reply

Your email address will not be published.

Back to top button