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Comment by Zenst | Hacker News Reader

I'd be interested how well electric cars faired in Norway as I would expect the colder months would impact the battery performance (reduce range). Which makes me wonder if manufacturers do any country adaptations for the local climate.

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https://www.tesla.com/blog/tesla-superowner-arctic-circle

The temperature dropped to -40 degrees Celsius. It was so cold that the trains couldn’t operate and the diesel in the buses froze. But the Model S was just fine.

Money quote:

“We found out that it’s a super winter car,” says Jens. “It’s so fantastic. It’s much easier and better than an ordinary car.” He likes that you can heat the Model S remotely via an app, so that there’s no ice or snow on the car when you’re ready to drive it. He also says the winter range is almost the same as the summer range. In December, he and Røsnes took the Model S to an ice hotel in Sweden, 200km from Narvik. The temperature dropped to -40 degrees Celsius. It was so cold that the trains couldn’t operate and the diesel in the buses froze. But the Model S was just fine."

In an old book about the development of the Prudhoe Bay Oil Field in Alaska, it was called Alaska Crude if memory serves, they described having to burn fires beneath the oil pans of their trucks to unseize the moving parts because the oil had frozen solid.

EVs seem obviously superior in this department, at least when it comes to cold enough temperatures to freeze engine oil.

Yes, I've seen Ice Road Truckers - scary job. Also that environment would be the true test of any EV truck. Which is an area far more in its infancy compared to cars.

Charcoal briquettes in a roaster pan can be useful there too, if you're ever in that situation. You get the radiative warmth without the flame (once it's burned down).

Gasoline cars have an optional engine block heaters, which not even an expensive option that heats up engine block and oil making the car nice and toasty as soon as heater inside the car is turned on.

Engine block heater is usually connected to a timer with an alarm, that turns out about 40 minutes before you need to leave.

Tesla is a nice car, but its not like this kind of technology hasn't been used before, especially in a country with a cold climate.

> He also says the winter range is almost the same as the summer range.

That's really interesting, and I'd be curious to know if others share this experience.

I have a plug-in hybrid (Ford CMAX) and live in the Bay Area, which has very mild winters. But even here, the range drops substantially when the temperature is "cold" (below 40° F). Then you turn on the heat, and the range drops even further. My typical experience is that the range is about -30% if it's under 40° outside, and turning on the heat knocks off another 25%.

Things may be very different in a Tesla (which obviously has a much larger battery), but presumably the same rules of physics apply?

They might be doing more insulation with their battery, they might even be keeping it warm via some tech ford doesn’t have access to.

Tesla uses a liquid coolant and active thermal management for battery conditioning. Model S and X have a dedicated battery heater, the Model 3 uses the motor and power inverter to warm the battery.

So would the model 3 be a lot more effected by cold than the S?

Anecdotally only (I don't have data), it appears so from Model 3 owner complaints on Tesla Forums and Reddit (it could be selection bias; Model 3 owners are more likely in my opinion to park outside or on the street than a Model S or X owner who will garage the vehicle). A recent software update attempts to mitigate the issue, but there's only so much physics you can solve with software (similar to how Tesla cheaped out on a ~$15 rain sensor and tried to use machine vision to handle automatic wipers, and it still doesn't work well).

https://forums.tesla.com/forum/forums/model-3-lr-awd-does-no...

I think he is either lying or not remembering correctly. Regenerative braking is severely impacted in winter. BUt maybe he drives mostly long distances on highways rather than in towns.

Only if you've allowed the battery to cold soak. Once warmed up, regenerative braking operates as expected (or if you plugged in overnight). Point to ICE vehicles in this regard, but only because they waste so much energy to heat.

Need to Supercharge/Fast DC charge? Do so before you park for the night while the powertrain is still warm, not in the morning.

>It was so cold that the trains couldn’t operate and the diesel in the buses froze. But the Model S was just fine.

This doesn't seem to align with real world results from the Tesla forums, subreddit, and Twitter. Lots of complaints about reduced range and slow charging during the recent cold snap.

Whats the point of pretending that battery performance doesn't suffer in cold temperatures? Is this really up for debate with current tech?

The reduced range isn’t that bad and most trips are relatively short and nowhere near draining the battery.

Lithium batteries have different temperature ranges based on what they are doing. Looking at an LG datasheet I pulled online (https://www.powerstream.com/p/LG-ICR18650HE2-REV0.pdf) you can see:

Operating - Charging: 0-50C

Operating - Discharging: -20-75C

Storage (1 month): -20-60C

So starting at -20C you run into trouble! Many people forget that the charging temperature range is narrower, but luckily if you are connected to a charger you could use some of that energy to run the Battery Thermal Management System.

My Model 3 gets about 70% of range in freezing temperatures, (25F, or about -5C). That's driving 75MPH with the butt warmer on. (About 115KPH.)

The range improves if I turn the butt warmer off and the heat down.

Yes the heating would be a mare factor in an electric vehicle compared with combustion flavours that produce heat.

I don’t think the Tesla has a heat pump yet, which would affect those figures.

Our older Leaf had bad range in the cold, and I think it had a heat pump.

I thought Tesla used a system to bring waste heat from the motors and battery into the cabin? Maybe that's only the S, because the 3's motor is more efficient?

It was an interesting winter for Tesla owners

https://www.thedrive.com/news/24944/these-are-all-the-issues...

Electric cars are often second cars in family. They're nice for short distances, like commute to work.

For long distances - and distances on road in Norway can be very long - internal combustion engine and its range still rules.

Sorry for the paywall, but I was reminded of this article in the Economist about the popularity of the Toyota Prius in Mongolia. One reason is low prices, but another is that they will start in extreme cold when ICE engines can't: https://www.economist.com/asia/2018/12/22/everyone-in-mongol...

cold climates are better for batteries than hot.

I really want that to be true, but try having your car battery die 3 times in a single week of -44 degree celsius (-47 fahrenheit) weather. Or, less dramatically, watch your phone go from 100% charged to 5% charged in just 30 minutes in that same temperature.

I'm no physicist, but anecdotally, you are very very wrong.

UPDATE: See hwillis' comment below. I'm so very very wrong, and am ashamed of my ignorance.

It is actually true. The battery stores just as much energy when it's cold, and has higher efficiency. The problem is that that efficiency drops dramatically as you try to pull more power.

A very simplified explanation would be that the charge carriers have a harder time moving quickly through cold electrolyte. This results in a kind of drag (most of which is actually literal drag) that results in a lower voltage on the output. Your phone measures its charge via the voltage (partly), so when it starts pulling more power it suddenly registers much lower voltage. If you turned it off and let the voltage recover, it would show as charged again.

Normal lead acid batteries will fail for the same reason; they can't push amps at low temperatures. If they were heated up they would work fine and they will have lost less charge than if they had been sitting at room temperature. Electric car batteries are the same, but the cold temperature enables to push much more power for longer without getting too hot.

Please do not compare phone batteries to large, carefully controlled and well-treated batteries like those in new EVs. They are totally different animals. Phone batteries are probably the most brutal of all common battery applications; they are used as heat sinks, have zero temperature control, and regularly experience forces and temperatures that are way out of spec.

I retract my comment. This is absolutely fascinating.

Thanks!

Unless they made the battery protect itself from the cold with some kind of thermal management system ? Such a system could run in external power when plugged in, and as a safety be able to run on it's own power, draining the battery of course.

they already use this approach. batteries have its own thermal management system.

True. Range is reduced but the degradation is slower. Based on complaints it seems Nissan Leafs smaller batteries with crummy thermal management degrade fairly quickly in hot climates. But are 'fine' in mild climates.

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