Keeping the battery warm

[andaconda]

Decreased my charge limit to 5 AMP’s And increased my charge level to 90% so that the battery would stay warm in this frigid weather.

So this is obviously working - because the interior is at -9F and the heat from the battery must be warming the interior slightly. Climate is off inside the car. The car has stayed at 84% charge for the past 24 hours, and the app states the the battery is heating for optimal performance.

 

[DesertSilver]

I have a few questions:

1. You can access the car through a local IP???
2. If so, why not just use the app?
3. Genuine question, what benefits are you getting by keeping the battery warm? I was understanding that a warmer battery will get you a faster charge rate when DCFC’ing, but not aware of what the purpose would be in general.

EDIT: Oh never mind about the local IP, I feel dumb. The screenshots looked like they were touching each other and I thought the IP address was the top of the screen of the car settings.

 

[jjrandorin]

1. That IP has to be whatever app they are using to look at weather, its not the one for the car.
2. See above
3. There isnt any (benefit to just heating the battery while its sitting there). Warmer battery is good for DC fast charging as you mentioned, and also for driving to have full regen.

Unless this OP is going to a DC fast charger directly from this charging session (unlikely since they turned the charging speed down just to keep the car awake and try to heat the battery), or is about to go for a drive, wants full regen, and is unwilling to use the blended brake option, all they are doing is keeping the car awake and wasting electricity (and money).

 

[Watts_Up]

Unless this OP is going to a DC fast charger directly from this charging session (unlikely since they turned the charging speed down just to keep the car awake and try to heat the battery), or is about to go for a drive, wants full regen, and is unwilling to use the blended brake option, all they are doing is keeping the car awake and wasting electricity (and money).

I tried to understand the reason for keeping the battery warm when parked:

- It is true that the battery could not be charged when below freezing temperature,​

so you cannot get regen when driving the car just after been parked outside in the cold.​

​

- But after a while, when driving, the battery get warmer, mostly by transfering the eat form the motors.​

Using 1,22 kW (or 244V x 5A) just for keeping the battery warm is not necessary and not very efficient.

- The battery don't get damaged when keept cold, there is less energy available and you cannot charge it.​

 

[andaconda]

TEMPERATURE LIMIT: -22°F (-30° C) is a no no according to user manual ???

I've got a surprise by reading the Model S user manual (Page 25) : «Do not expose Model S to ambiant temperatures above 140° F (60°C) or below -22°F (-30°C) for more than 24 hours at a time.» This warning really surprises me for the cold part, because in Canada (places like Edmonton, Northern...

teslamotorsclub.com

I use this link as a guide. I figured anything below -22°F wouldn’t be good for the battery so plugging it in and doing what I did Will keep the battery a little more stable warm with our continuing sub 0 weather. Arctic blast has kept our temperature right in the -20s and -30s for the past 36 hours.

I figured five or six dollars worth electricity might save a little bit on the battery.

 

[jcanoe]

Alternatives:

Park in a heated garage,
Precondition several times a day using the Tesla app or one of the 3rd party Tesla energy/charging apps,
Do nothing (uses the least energy), the Tesla Model Y's battery pack will be fine.

The downside to having a cold battery pack are few:
Unable to charge or use a Supercharger until the battery pack temperature is at or above 40F/10C
Limited power available; normal driving is unaffected
Regenerative braking will be reduced or unavailable (this is now OBE for most driving scenarios as you can turn on friction braking when regenerative braking is unavailable. (This setting is under Pedals & Driving), will seamlessly blend the friction brakes with regenerative braking.)

Plug in and charge within a few hours of when you arrive home as the battery will be warm enough from driving to accept a charge without requiring additional battery heating.

I routinely charge at 200V/30A for ~90 minutes; there is a noticeable battery warming that happens while charging with 30A flowing through the battery pack.) Often there is full or almost full regenerative braking available following charging.

 

[andaconda]

And here I thought it was such a good idea… Well I guess I’ll just have to let it deep freeze, and forget it until I’m ready to use it.