Section 2
When shopping for an EV, a battery’s estimated range is the all-important factor to consider. There is a quick way to understand this at a glance — by checking its capacity, measured in kWh, Kilowatt-hours.
kWh stands for kilowatt-hours, which is a measure of how much energy something uses per hour or how much energy a battery can store. It’s not how many kilowatts are used in one hour!
The size of EV batteries is expressed in kWh. Like a car with a larger gas tank, an EV with a bigger battery will generally travel further, everything else being equal. A Mini Cooper SE with a 32.6 kWh battery, for example, allows you to travel around 110 miles (177 km). Whereas a high-end Mercedes-Benz EQS with a 107.8 kWh battery would travel about 453 miles (729 km) on a single charge. Of course, these are two very different vehicles, but even so, the smaller lighter Mini still can’t match the range of the bigger heavier Mercedes all because of that battery.
And then there’s kW which is short for kilowatt: a measure of how much power an electrical appliance consumes instantaneously. In the EV world, we use it when talking about the power output of charging stations.
Generally, the higher the output (expressed in kW), the faster an EV’s battery can be charged. For example, an 11 kW home charger can charge a Mercedes-Benz EQS in around 11h45m ⁽¹⁾, whereas at a 150 kW DC fast charger it’ll only take around 33 minutes ⁽¹⁾.
Your EV will have a maximum amount of power that it can charge at, though. Most fast-charging EVs will top out at 150 kW, but some can far exceed that to charge even faster — but more on charging soon.
EV batteries are designed to last 10-20 years. With built-in systems to prevent degradation, in many cases, batteries outlive the rest of the vehicle.
However, despite good life expectancy, EV batteries do degrade over time and lose their ability to maintain a full charge. But this doesn’t happen as quickly as you may expect – and nowhere near as quickly as your phone battery.
Current estimates ⁽²⁾ suggest EV owners can expect to lose around 2.3% of EV battery capacity per year. To put that into perspective, if you drive an EV with a 213-mile (349 km) range, you’ll only lose about 24 miles (38 km) after five years. And this weighs up well compared to an ICE vehicle. All vehicles lose some efficiency over time, but an ICE’s fuel economy declines ⁽³⁾ at a much quicker pace (especially when poorly maintained) compared to an EV.
The good news is most EV manufacturers provide 8-10 year warranty or a set mileage warranty on the battery. Tesla ⁽³⁾, for example, offers Model S and X drivers an eight-year warranty or 240,000 km with a minimum of 70% battery capacity retention within that period. Hyundai offers its Sonata Hybrid drivers a lifetime battery replacement guarantee. So it’s worth double checking what kind of guarantee your potential EV comes with.
Compared to ICE vehicles, EVs require little to no maintenance. If you don't take care of your EV's battery, it could wear out faster. Follow these tips from the start to make your EV battery last longer.
1. https://ev-database.org/car/1484/Mercedes-EQS-580-4MATIC
2. https://www.geotab.com/blog/ev-battery-health/
3. https://www.hallvw.com/blog/do-cars-become-less-fuel-efficient-as-they-get-older/
4. https://www.caranddriver.com/research/a31875141/electric-car-battery-life/
5. https://www.jdpower.com/cars/shopping-guides/how-to-maximize-ev-range#:~:text=The%2080%2F20%20Rule%20for,it%20drop%20below%2020%20percent
6. https://circontrol.com/how-do-heatwaves-affect-electric-vehicle-batteries/#:~:text=However%2C%20it%20is%20less%20well,in%20electric%20vehicles%2C%20are%20affected
7. https://wepoweryourcar.com/blog-how-to-look-after-your-ev-battery/#:~:text=Just%20like%20with%20a%20petrol,EV's%20battery%20and%20overall%20health
8. https://thenextweb.com/news/is-fast-charging-bad-ev-battery-degradation
