Why Your EV Won’t Fill Up In Five – Watts Up With That?

Guest Post by Willis Eschenbach

Well, it’s happened again. The tech press is in full swoon, the Twitterati are high-fiving in the digital aisles, and the battery boys at Huawei are strutting around like they’ve just reinvented fire.

“Solid-state battery! 1,800 miles of range! Five-minute charge!”

The headlines practically write themselves. If you believe the hype, we’ll soon be zipping across continents on a single charge, stopping only long enough to grab a coffee while our car slurps down enough energy to power a small hospital. Here’s Huawei’s claim:

Huawei, the Chinese technology giant, has recently made waves in the electric vehicle (EV) industry with claims of a groundbreaking solid-state battery that could redefine the future of transportation.

According to reports from TechRadar, Huawei asserts that this new battery technology can deliver an astonishing range of up to 1,800 miles on a single charge while achieving a full recharge in under five minutes. If verified, these specifications could position Huawei as a formidable player in the EV battery race, challenging established leaders like Tesla, BYD, and CATL.

But, as usual, reality is hiding out in the fine print, ducking the spotlight while the PR machine does its victory lap. Nobody wants to talk about physics. Nobody asks how, exactly, you’re supposed to pour Niagara Falls through a garden hose.

Let’s start with the chemistry, because that’s what gets the headlines. Huawei, CATL, BYD, and every battery startup with a logo and a LinkedIn page are racing to show off lab results with solid electrolytes, nitrogen-doped sulfide electrodes, and energy densities that would make a Tesla blush. Yes, it’s impressive. Yes, it’s real science. Yes, the batteries likely exist, even if only in lab versions.

But chemistry is only half the story—the easy half, frankly. The hard part is what comes after: getting all that energy in and out of the battery without melting the neighborhood. Let’s do some back-of-the-envelope math, my favorite kind.

Charging a 600 kWh battery in 5 minutes isn’t a “nice to have” kind of deal. It’s a “requires the power output of a small hydroelectric dam” situation.

Energy equals power multiplied by time. So: 600 kWh divided by (5/60) hours is 7,200 kW—7.2 megawatts—per car. That’s not a typo. MEGAwatts. Per car. That’s the kind of load that would make your local substation break out in hives.

And it’s not just the grid. You’ll need:

• High-voltage wiring thicker than your wrist
• Transformers the size of shipping containers
• Power cables with active cooling, or else they’ll melt like a cheap extension cord at a Fourth of July barbecue
• Buffer batteries to keep the grid from doing a faceplant every time someone plugs in their new wonder-car

And don’t get me started on “green electricity.” The fantasy is that we’ll run this whole show on wind and solar, but unless you’re planning to build a solar farm the size of Luxembourg in every city, you’re dreaming. Fast charging at this scale is not compatible with the current “green” grid, and won’t be for decades—if ever. A couple of charging poles and a few rooftop panels aren’t going to cut it. We’re talking industrial-scale power plants, and even then, you’re right on the edge.

Here’s the cold hand of physics. Car batteries are at around 400 volts or so. 7.2 megawatts divided by 400 volts gives us 18,000 amperes. Per car. The typical US house has a 90 amp service, coming in on large overhead or underground cables. I’m sure you can see the problem …

To deliver 18,000 amps per car, you need connectors that look more like fire hoses than anything you’ve seen at a gas station. These electrical cables must be actively cooled, or they’ll turn into modern art. Cables are rated by their “ampacity”, which is how many amps of electricity they can carry safely without overheating. According to the NEC ampacity charts, the largest standard copper wire size, 2000 kcmil, has an ampacity of only 750 amps at 90°C, and we need an ampacity of 18,000 amps. (A “cmil” is a circular mil, which is the area of a circle 1/1000 of an inch in diameter. A “kcmil” is a thousand cmils. And no, I don’t know how many cmils there are in a bushel …)

A 2000 kcmil cable is about an inch and a half (3.8 cm) in diameter. Here’s a single 2000 kcmil underground direct-burial cable … and you’d need 24 of them to handle 18,000 amps.

The problem is that if you put more amperes of electricity through the cable and exceed the cable’s ampacity, it melts. Which is why you’d need a serious cooling system for charging cables if they are to be of a useable size … and if the cooling fails, you don’t want to be anywhere near the cable.

And if a few hundred cars plug in at once without a buffer? Say hello to an instant blackout.

The battery companies don’t care. Their job is chemistry. The rest is “someone else’s problem”—which is to say, yours. Or your city’s. Or your utility’s.

Who’s going to pay for the grid upgrades, the transformers, the buffer batteries, the land, the cooling systems, the huge connectors, the maintenance, the insurance? If you don’t own an electric car, are you ready to pay for your neighbor’s five-minute charge via higher taxes or utility rates? And if you do own an EV, are you prepared to shell out $500–600 per charge just to cover the infrastructure?

Here’s the bottom line: rapid charging is a lab dream, not a real-world solution for EVs. Technically, it absolutely works. Practically, fuggetaboudit. For most people, charging will still be a 30–90 minute affair—if not longer. Maybe that’s why Toyota, BMW, and Mercedes are quietly tiptoeing back to hydrogen, hybrids, and expensive e-fuels made from hydrogen plus CO2.

The electric car revolution is here, but the real revolution that’s needed isn’t in the battery—it’s in the ground, in the cables, in the substations, in the cable cooling systems, in the grid, in the generators, in the transformers, and in the cold, hard economics of power delivery. So before you run out and buy that car with “five-minute charging,” maybe ask yourself: Who’s building the grid? Who’s cooling the cables? And who, exactly, is paying for this party?

Because until someone answers those questions, the only thing getting charged in five minutes is your credit card.

My best to all, petrolheads and ampereheads alike.

w.

Yeah, I know you know, and I’ll tell you again anyhow: When you comment, please quote the exact words you are discussing. It avoids endless misunderstandings.

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