How long did your last visit to the gas pump take? Three minutes? Five minutes? The truth is, you probably didn’t even think about it. For owners of electric cars, filling up is a whole different story.
Quickly recharging an EV’s battery pack is a far more delicate procedure than simply pouring gas into a tank. It requires surging certifiably lethal levels of power into lithium-ion battery cells prone to overheating and runaway chemical reactions. Consequently, “fast-charging” an EV somewhere like a Tesla Supercharger is actually pretty slow. We’re talking 20 minutes to an hour for a solid charge, depending on a particular vehicle’s capabilities.
That needs to improve—and fast—to get more Americans to buy electric vehicles and stop killing the planet. The good news is that researchers, car companies and battery startups are innovating quickly to cut charging times down to a more palatable 10 minutes. But getting to the point when refueling an EV happens just as fast as filling a combustion car—in five minutes, let’s say—isn’t happening anytime soon.
Why EV Fast Charging Is Hard
There are a couple of persistent hurdles standing in the way of lightning-fast charging utopia. And you need to get the very basics of how batteries work to understand them.
At a fundamental level, lithium-ion battery cells store and release energy using charged particles (lithium ions) that flow between a positive electrode (the anode) and a negative one (the cathode). Hooking a battery up to a power source sends the ions swimming toward the anode, but forcing them to do so too rapidly produces nasty side effects. In the best case, these issues may diminish a battery’s capacity and cut short its usable lifespan. In the worst case, they can make the whole thing go kablooey.
The biggest problem is lithium plating, explains University of California, Berkeley chemical engineering professor Bryan McCloskey. If you send too many ions barreling toward the anode all at once, they can accumulate permanently on its surface as deposits of lithium metal, which “likes to react with essentially everything.” In extreme cases, McCloskey says, lithium plating can cause short circuits and violent battery fires.
Pushing lithium ions around too vigorously can also produce undue friction and cause overheating. Just like lithium plating, that can spark unwanted “parasitic” reactions that degrade a battery’s performance, McCloskey says.
This doesn’t mean all EVs are total duds from a charging perspective, but it does mean that even the fastest-charging models may not blow away drivers who’ve been pumping gas their entire lives.
The Hyundai Ioniq 6 can replenish its battery from 10%-80%, the equivalent of some 250 miles of driving, in 18 minutes. California startup Lucid Motors claims its high-priced Air luxury sedan can add 200 miles of range in 12 minutes. (Nobody really thinks about EV charging time in terms of empty to full because charging slows to a crawl as a battery nears 100%. More common benchmarks are 200 miles or 80%.)
The key to speeding things along is figuring out ways to allow lithium ions to move around more freely inside a battery without dealing too much of a blow to energy density. That’s what McCloskey is working on as part of a U.S. Department of Energy program aimed at creating batteries that can reach an 80% state of charge in 10 minutes or less.
You can’t buy a car that charges that quickly yet, but they’re coming. And the impact of that advancement may be far more profound than just saving drivers a bit of time in their day.
Faster Charging Could Supercharge EV Sales
Faster, more convenient and more appealing charging will be a crucial driving force for the next wave of EV adoption—the wave that encompasses everyday buyers, not just enthusiasts. People aren’t happy with the state of EV charging, and it’s tough to sell regular Americans on a technology that’s unfamiliar and also sometimes sucks.
Today’s average fast-charging session lasts 31 minutes, according to JD Power, a research firm that surveys EV buyers. Drivers aren’t exactly thrilled with that, most recently rating their satisfaction with fast-charging speeds at a dismal 609 on a 1,000-point scale.
“What we have right now is not fast enough, or we wouldn’t be looking at scores that are quite so low,” Brent Gruber, Executive Director of the firm’s EV practice, told me.
Even as charging networks have upped their game and vehicles have become more technologically advanced, that satisfaction score has decreased over the last two years, a trend Gruber attributes in part to changing demographics among EV shoppers. Early adopters were sufficiently jazzed about their Teslas to overlook time-sucking pit stops. Mainstream buyers aren’t so forgiving.
Public charging will only grow more important as the EV market flourishes. Most Americans who’ve bought EVs thus far live in single-family homes where they primarily plug in in their garage or driveway, Gruber said, but more and more apartment dwellers who rely heavily on public charging are entering the mix.
Batteries Are The Bottleneck, But Things Are Changing Fast
Today’s most powerful charging stations can dispense enough juice to, in theory, fully recharge a moderately sized battery pack in something like 10 minutes. It’s the batteries themselves that can’t handle that firehose of current. But that’s poised to change.
“Existing fast-charging infrastructure is not only available, but also largely underutilized,” says Chao-Yang Wang, a battery researcher at Penn State University who’s developed cells that can recharge to 80% in less than 10 minutes. His technology uses an ultra-thin nickel foil to preheat batteries to 60 degrees Celsius prior to charging, preventing lithium plating and allowing for better heat dissipation. He says his cells are undergoing testing by multiple carmakers.
Wang believes that ultra-fast charging could solve a slew of growing pains plaguing the transition to zero-emission transportation. If drivers knew they could recharge in the time it takes to use the restroom, he argues, they’d have more peace of mind to take longer trips. Plus, they wouldn’t demand 300 or 400 miles of range and the big, expensive, resource-rich battery packs that sort of mileage requires.
“Maybe every two days each person needs three gallons of water, but we don’t carry three gallon-sized water bottles,” he says. “We carry a liter-sized bottle because we can refill the water everywhere and anytime, right?”
Israeli startup StoreDot developed battery cells that can charge from 10%-80% in 10 minutes using an anode made from silicon, rather than the typical graphite. Dubbed 100in5 (referring to 100 miles of range in five minutes), the technology will power the Polestar 5 sedan when that vehicle launches in 2026. If it’s ready in time, the company may swap in its next-generation chemistry, 100in4, StoreDot CEO Doron Myersdorf told me.
What’s next?
A 10-minute charge to 80% pushes the boundaries of our current charging infrastructure. Speeding things up to a gasoline-like five minutes may be possible in theory, experts say, but would necessitate installing public chargers that can serve up roughly twice the power of today’s most potent units, which are rated at 350 kilowatts and are still rare.
“Five minutes is certainly a stretch goal. There’s no question about that,” McCloskey said. “But at the same time, I don’t think it’s entirely out of the realm of possibility.”
StoreDot is more optimistic, touting plans to produce a 100in3 chemistry in 2028, followed by a 100in2 cell in 2032. Myersdorf thinks 700-kilowatt public chargers will be commonplace down the line, but acknowledges that that infrastructure evolution won’t be swift or easy.
“Five years from now, I think 350 will be a baseline kind of station,” he told me.
Disappointed that gasoline-rivaling recharging isn’t right around the corner? Don’t be. There’s a compelling argument that says we should quit trying to map our notions about gas cars onto EVs.
One of the best things about battery-powered cars is that with a fairly basic electrical connection—one far cheaper and simpler than the mega-powerful plugs at highway rest stops—you can recharge one slowly just about anywhere: on the street, at the office, in a parking garage, at the mall. Harnessing the true potential of EVs may mean investing in lots and lots of slow-charging hookups that can keep cars topped up whenever they're parked, which, importantly, is most of the time. That’ll require a paradigm shift in the way we think about driving.
So maybe cars are just fine. It’s our brains that could use some rewiring.
Hyper-Fast EV Charging Is Coming To Supercharge The EV Transition - InsideEVs
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