Hello. New here. Heard that excessive heat inside the vehicle when parked is bad for the batteries, and so one should keep the interior cool via the app. I doubt this is true, but hey, why not ask the experts?
In extreme temperature ranges, yes. From the manual: Pg 93: In addition to cooling the interior, the air conditioning compressor also cools the Battery. Therefore, in hot weather, the air conditioning compressor can turn on even if you turned it off. This is normal because the system’s priority is to cool the Battery to ensure it stays within an optimum temperature range to supportPg 141: Do not expose Model 3 to ambient temperatures above 140° F (60° C) or below -22° F (-30° C) for more than 24 hours at a time There are 3 options in the UI to control this as well. Off: No passive cooling No a/c: blower only On: basically climate control
Keeping the interior cool does nothing for the batteries. They have their own cooling system, controlled by the computer. You do not need to do anything. Perhaps keeping it in a garage on those really cold days might be good.
I'm going to second and emphasize what @Uncle Paul said. They intend to sell these cars for people to own and use them as a car, not as a science experiment. They don't need you to do things to prevent the cars from letting their batteries be messed up. If there's something you shouldn't do, the car will display a warning for you. If there's something it needs to do, it will just do it, without you needing to remember or do anything. The interior temperature control is more for whether you want to spend the energy for protecting the heat degradation of your interior materials. Like dashboard and leather seats can get kind of messed up and cracked from years of 140+ interior temperatures in the summer.
Maybe in extreme like -20f the battery will warm itself for protection BUT I believe it normally only warms to charge or to get regen to function which is just another way of charging. Far as the interior temp, stop and think about the barrier that needs to be between the cabin and the battery that in extremely rare cases can catch fire, and there is carpet. You really think interior temp plays a big roll in pack temp when the pack has it's own temperature controls? The suggestion that the interior temp is a meaningful factor in pack temp is pure silliness I do let the car use cabin overtemp protection but I do so for comfort and because I am concerned extreme temps might contribute to main screen failures in my Model S. I don't have any data to back that up.