I think there is near unanimous agreement that the cars will never do that heating if they are parked and not plugged in.
In the swedish forums and facebook groups its not.
I guess more or less any “fact” you see about batteries etc. is wrong.
One interesting thing is how to handle the car if you have a unexpected behaviour.
I learned the same week I bought my first Tesla that you should use the menu and shut down the car, as that what is written in the manual.
Holding the two steering wheels buttons down restarts only the touch screen, also by the manual.
I see at least one post every day on (Swedish) Facebook groups about that the car do not work as it should and the recommendation is to use the steering wheel button to reboot the car (for just about any reason, for exampke that the charging port doesnt open as it should).
The most fun part about that is that the manual specifically states that pressing the brake at the same time as rebooting the touch screen does not have any effect and that it do not change anything.
Still 50% of the posts it about “press the brake for a extra deep reboot”
I think that is what some of us are still curious about and haven't seen tested with evidence. If staying that cold for a long time is actually damaging,
From all I have seen in research there has been no cold tests that shows that extreme low temps is bad at all.
The lower the temp the lower the calendar aging. Panasonic NCR (NCA Chemistry) has down to -20C in the spec for storage, but I have seen tests down to -40C with no damage (on the contrary virtually no calendar aging)
I do not know why Tesla has set the maximum one day below -30C but I follow that by activating charging (to heat the battery) when the car is parked at work for one week in cold wx.
It is (very) possible that the -30C ”rule” comes from the Panasonic min temp for discharging the battery, -20C.
If we drive the car and park it in -30C or colder it probably takes about a day for the battery to go beyond -20C.
If we can not begin the use by connecting the charger and get the battery heated, the battery need to heat itself or drive cold, both will include discharging below -20C in this case, which is not good for the battery.
and Tesla warns not to do it, then the sensible remedy should be simply to plug it in. If it has a source of energy to draw from to prevent damage and won't be depleting the battery, shouldn't it use that? I would think so, but I don't recall seeing any answer on that either way.
I do not know for battery temps below about -20C, as I have activated jte charging to heat the battery.
But I know that down to about -20C cell temp (and ambient down to -40C) there is no battery heating done, with or without the car connected.
For example right now the car is not connected, and has been parked for 36 hours, with about -20 for the last 24hrs.
It is easy to see in Teslafi without even going to the car. The last day is here, the car has been sleeping all the time. Sleeping means the big battery disconnected and the small lithium LV batt can not heat anything. So its very clear no battery heating has been done since it was parked.
(I usually also check with SMT, and seeing the SOC with a 0.1% resulotion also males it clear. On the summer it uses ~0.1% and ~0.1 kWh each day =average 4-5W so if the car only used 0.3% and 0.3kWh for three days; there was no battery heating.
So I would love to see a car sit in a -40 C situation for a week, hooked up to a wall connector that has an energy meter running to see if it draws any power to keep it above -30 C battery temperature.
Yes it would be nice, but I would not do it with my car even if I actually do not think it hurt the battery.
For me its a hypotetical question really.
The swedish Facebook groups about tesla mostly seem to have the myth that the battery is always heated and newer let below 0C etc. The myths about battery warming is never ending and all are already confirmed to be myths when I checked.
The only thing left to check would be the -30C cell temp, but I think that doesnt need to be checked
