Is fast charging bad for your EV battery?
How much do they affect the battery’s state of health?
Story byIoanna Lykiardopoulou
Ioanna is a writer at TNW. She covers the full spectrum of the European tech ecosystem, with a particular interest in startups, sustainabili(show all)Ioanna is a writer at TNW. She covers the full spectrum of the European tech ecosystem, with a particular interest in startups, sustainability, green tech, AI, and EU policy. With a background in the humanities, she has a soft spot for social impact-enabling technologies.
Get the TNW newsletter
Get the most important tech news in your inbox each week.
Also tagged with
Related Articles
More TNW
About TNW
So, how bad is it really?
Studies reveal there is indeed a noticeable deterioration rate.
According toGeotab, for instance, the battery’s state of health (SOH) is affected by how often a vehicle is using DC fast charging.
The telematics company specifically examined EVs operating in hot weather conditions that have proven to be more straining for the battery.
Battery degradation appears to be strongly correlated with the use of DC chargers for vehicles in seasonal or hot climates.
Compared toEVs that don’t use fast charging at all, vehicles that primarily douse it show a battery deterioration by nearly 0.1%.
The graph below compares how Level 1 and Level 2 (AC) chargers affect the battery’s state of health:
It’s evident that Level 2 charging has the least negative impact, reaching 0.9%. What’s more, both Level 1 and Level 2 charging damage the battery less than the frequent use of DC chargers.
We can observe, however, that the difference between Level 2 and Level 3 isn’t that big: approximately 0.1%.
The Idaho National Laboratory (INL) has made similarfindings. The US Energy Department lab concluded that while an electric car’s battery will deteriorate faster if its only power source is Level 3 charging (which is almost never the case), the difference isn’t particularly pronounced.
The INL tested two pairs of the 2012 Nissan Leaf under the exact same conditions over the course of a year, in Phoenix, Arizona.
The first pair was charged with Level 2 chargers, and the second pair with Level 3 fast chargers.Both pairs were charged twice a day.
Afterall four test cars had been driven for 80,467 kilometers, the Level 2 vehicles had lost around 23% of their original battery capacity, while the Level 3 cars were down by around 27%.
What’s the takeaway?
Fast charging deteriorates the battery faster than Level 2 charging, but that’s not necessarily worrisome for your EV, providing that DC chargers aren’t the primary source.
Still, prolonging a battery’s life is a pretty big deal given its cost, so there are a few things that we can do even if weenjoy the convenience of fast charging:
