The Chinese automaker BYD shocked the world this month when it announced ridiculously quick charging times for its next-generation electric cars. BYD says these vehicles will accept 1,000 kilowatts of charging power—about four times more juice than your typical Tesla—leading to charging times as low as five minutes for 250 miles of range. 

It’s been clear for years that charging times across the EV world need to get faster to get more buyers onboard. But five minutes may just be overkill, said Andrew Cornelia, CEO of Mercedes-Benz High-Power Charging, during an interview on the InsideEVs Plugged-In Podcast this week.

“This is an amazing breakthrough. The industry will follow,” he said. “That said, faster is not always better.”

 

Today, most mainstream EVs take anywhere from 15 to 40 minutes to gain a significant amount of charge at a powerful enough DC fast-charging station. We’re talking enough energy for a couple hundred miles of highway driving on a road trip. Cornelia says that developing faster-charging cars is key, but that the industry is actually a lot closer to the sweet spot than it seems. 

“Do we need to charge in five minutes? The answer is probably no, because actually the average dwell time for filling up your gas tank is about 10 to 12 minutes,” he said. “So that’s actually the number that we’re solving for.”

Mercedes High Power Charging Stations

That makes sense. It may only take three or five minutes to fill a gas tank, but people often wind up grabbing a coffee or some scratchers too. (This leads to what is, in my opinion, the unforgivable act of parking your car at the pump. But that’s another story.) 

Moreover, he argues, people are thinking about charging times all wrong. It’s not about making charging as fast as possible all the time—but rather making the charging time fit the stop or activity you’re doing. After all, a big pro of EVs is that they can be plugged in and sucking up juice whenever they’re parked, whether that’s for five minutes or five hours. 

To take an extreme example, he says, 1,000-kilowatt charging would make no sense for a home garage, because you’re always going to be parked there for several hours anyway. 

“If you show up at a movie theater, you still don’t need 1,000-kilowatt charging. You need something that matches a two-hour dwell time,” he said. “If you show up at a coffee shop, maybe you want something faster, but still it’s a 15-minute stop to go in and out.”

As far as five-minute charging goes, “there’s only a limited number of use cases where that actually makes sense,” Cornelia said. 

Mercedes-Benz Charging Hub at the headquarters of Mercedes-Benz USA in Sandy Springs, Georgia.

Of course, Mercedes-Benz High-Power Charging is still focused on making charging stops as quick and painless as possible. It deploys 400-kW stalls, which dispense more than enough power for almost any EV sold in the U.S.

Plus, as you might surmise from Cornelia’s argument here, the company places a big emphasis on placing chargers at locations where drivers will have something to do for a little while as their cars fill up. It’s inked deals with retailers like Starbucks and Buc-ee’s, the chain of super-sized gas stations. 

Still, as a mic-drop moment that shows the future potential of EV charging, BYD’s announcement has a lot of value, Cornelia said. 

“This is important. It’s important to promote the message that charging can hypothetically and in certain use cases deliver power at this output and at this speed,” he said. “But it’s not the predominant use case.”

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