Heating and cooling batteries

[Frankieo]

My garage varies between 68 -76degrees. I stay plugged in overnight for charging. Will my car continue to cool or heat the battery to 70 degrees ? When is the car
sleeping. Someone said when sleeping all bets are off. I am constantly hearing a fan running in the frunk. I have a 2021 Model 3.
Frankieo

 

[jjrandorin]

The temp of your HV battery is something the car manages on its own, and not something you need to really be concerned with. it will not "heat or cool" your battery to keep it at 70 degrees, it will heat the battery when it needs to charge it, if it needs to.

Even if your car ends up with a snowflake on it when you get ready to go somewhere in the morning that just means that some capacity is locked out until the battery warms up. Unless you are attempting drag runs first thing in a snow morning, this also isnt something to worry about.

TL ; DR -- the car manages all that as it needs to, you do not need to do anything different or be concerned with heating your battery yourself, the car will manage all of that on its own.

The fans / heat pump will run for quite some time after driving to dry out the HVAC system.

 

[Sophias_dad]

My garage varies between 68 -76degrees. I stay plugged in overnight for charging. Will my car continue to cool or heat the battery to 70 degrees ? When is the car
sleeping. Someone said when sleeping all bets are off. I am constantly hearing a fan running in the frunk. I have a 2021 Model 3.
Frankieo

I don't know the exact specs, but I'm absolutely sure that there's a wide berth of 'don't do any battery heating or cooling'. Unless its beginning to charge, it won't bother heating the battery until at least below freezing(or of course when en-route to a supercharger), and I >think< battery cooling is generally only during supercharging.

The fan you hear might be the 12V battery charger, but that's nothing but a guess. I'd think it'd be in the rear seat area. Is it >really< a constant fan, or more of an 'I notice it often' fan?

 

[GtiMart]

The car runs the coolant pump continuously while it's awake. After you drive, it might take 5min but it could also take an hour before it falls asleep. As others said the ac fan runs for a while to dry the evaporator to prevent odors.
The car might wake sometimes to charge the 12V.
The car will not wake just to care about the battery temperature. Rest assured that 60-70C is very comfortable for your battery.

 

[joelliot]

The sound is probably the cabin fan that now runs after a driver to dry the a/c coils so they don't smell. As mentioned by others, the heating and cooling of the battery will generally only occur during preheating or charging the car.