Pretty sure the ones in most EVs today work fine at -10C, but they may lose some efficiency. The thing is, there's already mechanisms in some cars to generate waste heat specifically for this purpose. Tesla's already have the ability to run their motors 'inefficiently' generating waste heat, which can be pumped into the battery coolant and heat that. It's no better than electric strip heating, but it doesn't add any cost to the system.

The real benefit, in my view, to being able to charge at cold temps is to improve overall efficiency. If you have to waste some amount of power to heat the battery then that is power that could have been used to charge the car instead...

You bring up a great point. The battery spec is only given at -10C. That's a mild normal day's low temperature in winter in Minneapolis, USA. But it's often much colder than that for long periods of time. I wonder if this glassy layer they apply can handle -30C; a temp where above ground heat pumps are no better than electrical resistive heating.

https://ashp.neep.org/ for a list of heat pumps that perform well in cold weather.

The 5x delta is stated to be at 14F. That absolutely is within the reasonable operating range of a Model Y heat pump, not sure what you're citing?

It's true that there are very cold environments (Fairbanks winters, say) where in-car thermal management won't be sufficient to keep charging rates high. But those are the same environments where you can't even start a gasoline car without an engine block heater, and I don't see many "no cars in Alaska" arguments on the internet. Everything has limits, but I don't see this battery trickery having much of a home.

You can start gasoline cars just fine down to 20 or 30 below, so long as you keep a good battery in it. Sometimes big diesel trucks use block heaters but gasoline cars don't need them.

I live in a region where -40°C is not unheard of (it happens every winter and stays for up to several weeks). I've also been to another region (not far off) where -50°C is pretty typical.

Gasoline powered engines work just fine in these temperatures, although many cars come with auto ignition systems that start up the engine periodically throughout the night to keep it warm. Otherwise you might have to warm it yourself in the morning using a gasoline powered "torch" (or whatever it's called), which sometimes ends up with the car going up in flames.

So it's honestly pretty funny to read that EV work "down to -10°C". Although probably relatively few of us are desperate enough to be living in such conditions.

They work down to -10. And colder than that too. Apologies to Mitch Hedberg.

Only if they have the ability to stop charging if the battery pack is below freezing, and some way to heat the pack (and keep it) above freezing. Otherwise, charging in those temps will destroy the battery.

I think that's everything but the Nissan Leaf.

Leaf can heat the pack, just no cooling

Stock gasoline cars do not do well at those temperatures. In Alaska most people with sense use engine block heaters, plugging in every cold night. Besides the issue of having trouble just starting the car, you will put excessive wear and tear on the engine doing it regularly.

And in places like Fairbanks where -40 (F/C) is fairly common in the winter, even cars that merely have an engine block heater will have trouble. You need even more heating pads for the rest of the stuff under the hood of you want to keep a car reliable and healthy in that kind of climate.

Yes, and even then ‘healthy’ is not what people in normal climates think. It puts a lot of wear and tear on vehicles.

I can definitely say that old/USSR 2.7L gasoline engines for the military came with block heaters. But they were expected to start in -50C / -60F. Good luck getting anything out of an EV at those temperatures.

There's plenty of Norwegians on YouTube testing EVs down to those kinds of temperatures and they work absolutely fine, with the caveat that they won't charge until the battery warms up. Discharging Lithium batteries at really low temperatures isn't an issue, charging them is(because it actively damages them) - but even then the threshold is -32C or around that, easily overcome even with a simple resistive heater.

Norway is not "those kind of temperatures". They get a lot of snow, and maybe -5C and that is all because Gulfstream (the reason Murmansk does not freeze, and it's much farther into Arctic). Otherwise they get it easy.

Now when you move just a bit off the sea, the continental climate kicks in, and you have weeks of -15 -- -20C.

On discharging lithium chemistries at those temperatures or "easily overcame with resistive" let me say that: you just don't know what you are talking about.

The question is, how many people are legitimately living in areas where this is an actual concern in their lives? Outside of Alaska, Canada and Russia barely any place on Earth that relevant amounts of people live in, such low temperatures are a once-in-a-lifetime event.

The question is why you did not do your research before posting this insultingly dismissive missive.

I've succesfully started my rustbucket diesel from 2009 in -33C. It didn't sound too happy about it, but it did start and run and get to where I wanted