Is Fast charging bad for electric cars?

One of the most frequently mentioned features modern-day electric cars offer is fast charging. Fast charging allows you to charge your battery way faster compared to ‘’regular’’ charging, but it does come with a few caveats.

As such, fast charging enables you to spend less time charging, and more time driving. It is lead to believe that some fast chargers can offer up to 85% of charge in as little as 20 minutes. However, many aspects can negate that, and it’s essential to know which.

Indeed, frequent fast charging can negatively impact long-term battery performance, but that’s the case with almost all Li-Ion batteries on the market. All batteries tend to degrade over time, and after many cycles, they will lose their maximum charge.

After about 10-12 years, most EV batteries will become less and less efficient, which means that they will eventually have to be replaced entirely. This can cost upwards of $2-5k, and it is still unclear how these batteries will be disposed of.

How does fast charging work?

Fast chargers are designed with multiple connector pins which can deliver more energy. Some brands like Tesla have specific connectors which only work with Tesla superchargers, but they can also use other charging stations if you take advantage of the included charging adaptor.

Fast charging is actually Level 3 DC charging, this means that your car has a specific converter that converts AC into DC. They say that a DC fast charger can charge up to 3-20 miles per minute, while regular AC charging is not even in the same league.

  Do you have to hand wash a Tesla?

Modern-day DC fast chargers monitor the entire charging process as it takes place to ensure that the battery gets the right amount of charge at every moment. The charging station feeds the right amount of charge to preserve the battery and the entire charging system.

Most DC fast chargers work best with pre-heated batteries. This means that when your battery reaches its optimum charging temperature, the maximum kilowatt amount of charge is achieved. Before you reach maximum charge, the amount of energy offered is decreased to further preserve the battery.

Effects of long-term fast charging on EV and Hybrid batteries

Almost everyone has a cellphone of some sort these days, and almost all of them are designed to take advantage of fast charging. Even though such charging speeds enable you to charge your phone faster, after a while, you realize that your battery health percentage is becoming worse and worse.

It’s more or less the same with a larger car battery, but the levels of degrading are not as pronounced. A few years back, one study concluded that fast charging decreased up to 27% of the battery’s original capacity after a year of constant use.

On the other hand, the same model was also tested solely with Level 2 (Slow) charging and the battery lost around 23% of its original capacity after 12 months of constant use. Even though the differences are there, they are not as pronounced as many of us expected them to be.

It is worth mentioning that many aspects affect how a car’s battery will behave through time, but it is safe to say that fast charging does negatively affect overall battery health percentage to a certain degree.

  Do Tesla break down often?

How can I take advantage of fast charging?

First of all, fast charging is not available through a regular home circuit plug because they require way too much power and money. Most Level 3 fast chargers are available on highways and places where fast charging is most necessary.

It also depends on the type of car you have. Some cars like the Porsche Taycan have a maximum DC capacity of just shy of 270 kW, this means that the Taycan can theoretically reach 80% of charge in a little over 22 minutes.

Most Tesla Superchargers are only able of 120 kW at this time. It’s worth mentioning that a Level 3 charger also costs more when compared to a regular Level 2 slow charger. Be that as it may, make sure you follow the manufacturer’s recommendations on how and when to use fast chargers.

Try to use fast chargers only when you need a fast top-up, this means that you should primarily rely on Level 2 charging or regular home circuit plug charging which can take a few hours to charge. Perfect for an overnight charging session.

FAQ Section

Should I charge my EV overnight?

Charging your EV overnight through a slow charger is one of the safest ways of keeping your overall battery health in optimum condition. However, you don’t have to charge your car up every single night, as this is unnecessary in most cases.

If you do plug in your car whenever you park it, this might negatively affect your long-term battery efficiency, thus shorten the battery’s lifespan. It’s always best to just follow the manufacturer’s recommendations on how and when to charge your car.

  Best electric cars for a first car

Do EVs lose charge while parked?

Yes, but not all that much. It’s always best to leave your car parked with 70-80% of charge. This way you are always going to be able to just get in the car and go wherever you want. However, if you keep your car parked for an extended period of time, you are bound to lose over batter health.

Some cars even have specific features which enable you to engage extended park mode which disengages a few unnecessary systems in an effort of preserving your state of charge as best as possible.


Is it safe to keep my EV plugged in at all times?

In theory, it is not a good idea to constantly keep your car plugged in, but modern-day cars have lots of technology solutions that can negate many negative aspects of constant charging. This means that these cars can be left plugged in for extended amounts of time without negatively affecting the battery.

Be sure to ask your dealer/manufacturer how exactly you should maintain your battery if you want the best and longest EV ownership experience. Just don’t park on a public charging spot and leave the car there to block other EV owners from charging their cars.

Marko Mikulic

Why do you love writing about cars? I love writing about cars as cars are a huge personal interest of mine. I was raised in a car enthusiast community and ever since I was young, I always wanted to do car-related work.

Recent Posts