Changing to an electric car can be an exciting but daunting thought. You could be so used to the requirements of a fossil fuelled cars that you might be rather tentative about the change. You might expect there to be a bunch of confusing lingo that could make your head spin.

In my experience, EVs are not that different from combustion engine vehicles in practice, the fact that they are powered by electricity throws a bunch of new information into the mix. Therefore, I am going to help you understand the basics of an EV battery.

Know the Difference – kW vs kWh

You might think of batteries as the things you used to throw in the back of a flashlight. And you are not wrong, modern lithium-ion-based electric car batteries are not too dissimilar, they are just a lot better. EV battery size is measured in kWh, or kilowatt hours. But what is that?

A kilowatt hour is a measure of energy used by an appliance if it were kept running for one hour exactly. It is not how many kilowatts are being used per hour! This is a common misconception that causes a lot of confusion for those who are making the switch to an electric car. A kilowatt, however, is a measure of instantaneous power. All kinds of appliances like smart phones, laptops, microwaves, blenders, and car motors all have a watt or kilowatt rating. This is a measure of exactly how much power they require to be continuously supplied with power to run.

Let us say you have an electric motor rated at 150 kilowatt (kW) at peak power output. If you ran that motor for 30 minutes you would use 75 kWh of energy. 150 multiplied by 0.5 (of an hour) equals 75 kWh.

Often, Bigger is Better

If how far your electric car can travel on one charge is important to you because you are a fan of long drives, a good general rule to follow, would be to get a big battery. In other words, you want one with a large kWh rating as this will be able to power your new car for the longest period. Allowing you to continue your long Sunday drives.

The Nissan Leaf, which has is often thought of as the flagship for consumer grade EV cars, has under 200 miles of range, come in 40kWh and 60 kWh models. The long-range Tesla Model 3, which is considered the market leader for innovation in the EV car field, can go for over 300 miles of range, packing a 75kWh battery pack.

There are other factors that impact an EV’s range, like aerodynamics, motor efficiencies that could be brought own by a whole host of reasons, and how much power is drawn from other electronics in the car. It is not a cut and dry rule by it is a good way to ground the way we think about EV charges.


There are generally 3 levels of EV charge rate. They are often grouped by their kWh rating.

  • Slow (standard) chargers are rated at between 3 kW and 6kW. These are the most basic chargers you will find and the one you will probably be using at home most often because this kind of charger plugs into the wall in a home socket.
  • Fast chargers are rated between 7 kW and 22 kW. This is the kind of power you get from a dedicated at-home EV wall box make look out for this one if you decide to make the change to an EV car, or a destination chargers at shopping centres, and public car parks.
  • Super-fast chargers are rated at 50kW and up. These can charge your EV in amazingly fast times compared to the other two options. Some can even get to the 100kW market. A Tesla Supercharging station would probably fit into this category.

As you can see there is a wide variety of charging options to choose from so make sure that you get the highest kWh rating you can out of your solution. You will have a full charge quicker this way.

Ultimately, EV vehicles can be a big change to how you view motor vehicles. But with the right information behind you and a little patience it is well worth the change. With more and more models of EV vehicles coming out all the time, like the Audi E-Tron GT shown in the picture, the new Porsche Taycan and the Jaguar E-Type as typical examples, most of us can expect them to be the future of motoring.