Tech & AI

How BYD plans to make EV charging as fast as filling a gas tank


Chinese auto maker BYD made waves this week when it announced its new Han L sedan could add as much as 248 miles of range in as little as five minutes.

Unfortunately, the company was light on details, and it did not respond to TechCrunch’s request for clarification. So instead, we’ve scoured the web for information, filling in the gaps to determine exactly how BYD was able to make an EV that apparently can recharge as quickly as it takes to refill a gas car. 

What we found mostly supports the auto makers claims, with a few caveats.

Battery pack

Central to the Han L’s fast charging is its internal electrical infrastructure. It starts with the battery, which according to CarNewsChina citing regulatory documents, is an 83.2 kWh lithium-iron-phosphate (LFP) pack that operates at 945 volts. (In its marketing materials, the company appears to have rounded up and lists it at 1,000 volts). 

The battery chemistry is likely central to the car’s fast charging capability. LFP batteries have long been regarded for their stability and safety; they don’t catch fire nearly as readily as other types like nickel manganese cobalt (NMC). They can also charge faster because of some electrochemical quirks inherent in the cathode-anode design of an LFP cell. (There’s a great slide deck from the National Renewable Energy Laboratory that explains why in more detail.) 

To top it off, BYD has been working with LFP for years, and its latest battery architecture, known as Blade 2.0, is expected to debut in the new car. That experience has probably given the company’s engineers a good sense of how far they can push both the batteries and the electrical architecture.

Electrical system

Feeding the battery pack is a high-voltage electrical system that runs at 945 volts. Automakers have been pursuing ever higher voltages because higher voltages generates less heat, allowing more power to be delivered safely and efficiently. Currently, Lucid runs a 900-volt architecture in its cars, and several others like Hyundai Kia and Porsche operate 800-volt in many of theirs. With Teslas, it depends on the vehicle: The Cybertruck uses an 800-volt architecture while the remainder operate at around 400 volts, give or take, depending on the model.

Add it all up and the Han L can charge at up to 1 megawatt, or 1,000 kilowatts. The fastest widely available EV chargers in the U.S. today deliver only 350 kilowatts.

But even when running at 945 volts or 1,000 volts, the amount of heat generated by 1 megawatt charging is significant, and the cables to support it would have to be incredibly thick. Even slower, fast, charging cables like the ones that are attached to 350 kW chargers are wrapped in liquid cooling, further increasing their bulk.

Perhaps in an effort to make the charging cables more manageable, BYD has adopted what it is calling a dual gun approach: The car has two charging ports, each of which can plug into a 500 kW charger simultaneously. 

Together, they deliver one megawatt.

Range shenanigans

According to BYD, that allows the car to add 248 miles of range (400 km) in five minutes.

Unfortunately, drivers are unlikely to travel that far after such a quick charge. That’s because the Chinese equivalent of the EPA test cycle, the CLTC, is notoriously optimistic. It’s about 35% higher than EPA ratings, according to InsideEVs, which themselves are either spot on or optimistic depending on how much highway driving is involved.

Realistically, drivers can probably expect around 160 miles of range from a five-minute charge and around 280 miles from a full battery. For a more apples-to-apples comparison, it’s helpful to look at how long it takes to charge from 16% to 80% (in 10 minutes) or from 16% to 100% (in 24 minutes). No matter how you slice it, that’s pretty fast.

Charging strategy

But an EV’s charging speed is only as good as the chargers and how widely available they are. To that end, BYD is pledging to install more than 4,000 of them throughout China. Each charging station will require significant grid upgrades, though, as a 1-megawatt power draw would likely strain the existing infrastructure.

When will we see this in the U.S.? Don’t count on being able to buy a BYD Han L anytime soon, even if the approximately $37,000 starting price would give the market a welcome jolt. Chinese made EVs are currently subject to a 100% tariff, raising prices to the point where they’re not competitive.

But that doesn’t mean similarly fast charging will remain out of reach for Americans. Cars for sale today already can charge from 20 to 80% in 18 minutes, so it’s only a matter of time before automakers bring those times down.



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