New battery warm up before super charging

New battery warm up before super charging

I don't have the newest software update but I have read on here it includes a warming of the battery when routing to a super charger to maximize efficiency.....Just wondering what you all think about using this for just a cold battery in winter. As in, would I nav to super charger with no intention of driving there or using it, just so the BMS warms to minimize limited regen due to cold battery? Do you think Tesla will ever release just a 'warm the battery' function on the TM3?

No need to mention charging or warming cabin to warm the battery...This winter - neither had a solid impact of warming the battery in my experience (MN winters are COLD).

Let me know your theories if you have them...Thanks.

M3BlueGeorgia | 2019年4月9日

No theories, just reality.
If you Supercharge a cold battery, the battery has to be warmed before it can take the charge and has to get quite warm before it can charge at maximum speed. This is why people on multi-day road trips are strongly advised to Supercharge their cars when they arrive at their overnight location, instead of charging in the morning when it is cold.

In order to reduce congestion at certain Superchargers, Tesla is trying to ensure the batteries arrive warm (and ready to take a fast charge) by pre-heating the battery as the car gets near to the Supercharger, even if it only traveled shortish distance to get there.

Will people attempt to game this situation? Maybe a few will, but I really can't see how it would help much.

Will Tesla ever allow the driver to explicitly warm the battery on a Model 3? Maybe, and it wouldn't be a bad capability provided it wouldn't lose more battery than worthwhile.

Mike UpNorth | 2019年4月9日


What do you mean by 'game the system'?

I'm just looking for a better way to warm the battery in winter.

mrburke | 2019年4月9日

Pure speculation on my part:
I believe that the "warm the battery" on the way to the supercharger is in reality a "don't cool the battery as much" on the way to the supercharger.

So if that is the case, then I would say no.

Mike UpNorth | 2019年4月9日

@mrburke....Darn...But thanks for the speculation.

roger.klurfeld | 2019年4月11日

@mrburke: not true.

According to Sandy Munro, Tesla is going to stall the motor(s) on the way to the supercharger. This will heat up the transmission oil. The transmission oil will then go to the super bottle. There it will warm the battery coolant through a heat exchanger as the coolant goes through the super bottle. The heated coolant will then go to the battery and heat it. There is no other way to heat the battery, except a little as the batteries charge. Heating the inside of the car will have no effect. Munro calls the super bottle amazing engineering.

roger.klurfeld | 2019年4月11日
Mike UpNorth | 2019年4月11日


Cool info man....Any idea if all that can happen while the car is parked in my garage when its 10F degrees out?

billlake2000 | 2019年4月11日

Your garage is a Faraday cage and nothing will work in there.

roger.klurfeld | 2019年4月12日

@Mike UpNorth: I don't think so. I think the car has to be moving. Hence warming the battery on the way to a supercharger. Navigation to a supercharger tells the car to start warming the battery, but I don't know how many miles out the warming starts.

Mike UpNorth | 2019年4月12日


Yeah, was thinking the same. Especially since if the car had a battery warm up method I would assume it would already exist. Not a future OTA update.
But as I hope P is offered one day OTA - I hold out hope next winter I can warm the battery before leaving the house....

Roger1 | 2019年4月12日

If I recall correctly, the model 3 doesn't have a resistive heater to warm the battery and cabin. Instead, the motor is fed power out-of-phase that causes it to heat but not rotate. Heat generated by the motor transfers into the heating/cooling liquid loop which runs through the battery and cabin (see post by roger.klurfeld). Delivering power that is partly out-of-phase will allow the motor to turn while still creating excessive heat for transfer to the battery and cabin.

In my experience with a model S, the battery heater comes on when you pre-heat the car using the remote application but only if the temperature is really cold. I speculate that the battery temperature has to be below freezing. The battery delivers sufficient power for driving without difficulty but might not be able to support foot-on-the-floor acceleration. In the model S, regeneration is limited for an extended period and does not recover during short trips. In below freezing conditions, half an hour at highway speeds may be required to achieve full regeneration. Adding ultracapacitors to the drive electronics would really help preserve full regeneration and acceleration capability in cold climates. These comments are based on model S and model 3 may be different. I will know better next winter as a member of my family just took delivery of a model 3 LR.

jordanrichard | 2019年4月12日

Why are people overthinking this? The battery has an ideal temperature to be at for efficiency and charging. All this update does, is preheat (if needed) the battery as you approach a supercharger. Of course it only knows that you are going to be stopping at a charger via you using the nav system. We as owners don't know what that ideal temperature is and we don't know how far out from a charger it will starting heating up.

That's it, nothing more, nothing less.

Mike UpNorth | 2019年4月12日


Who's over thinking? My OP was about heating the battery when stationary. Just wondering if its possible now that T is talking about warming of the battery when traveling.

Carl Thompson | 2019年4月12日

"Why are people overthinking this? The battery has an ideal temperature to be at for efficiency and charging."

Obviously there are two _different_ ideal temperatures involved... one for efficiency and one for supercharging. Otherwise the car would keep the battery at your single ideal temperature all the time and there wouldn't need for a separate on-the-way-to-the-supercharger mode.

This also very obviously means that this mode must _decrease_ efficiency.

But Tesla saves money by decreasing supercharger visit times. That way they don't have to spend so much to increase capacity at the superchargers. But they are saving money at _your_ expense... The decreased efficiency means you pay more to travel the same distance.

But the decreased efficiency also means you need to charge more often. I guess Tesla is gambling that that doesn't translate into extra supercharger trips because if so they'd lose the advantage they gained. I wonder if they truly modeled this or if they are simply doing it because it seemed like a good idea to someone?

ajbutler45 | 2019年4月12日

@Mike UpNorth So would heating a battery while pretending to drive to a Supercharger be more efficient use of the cars energy then just drive with the cold battery? To me it seemed like most of the extra winter time energy was to heat the cabin. On a 20 mile commute the cabin spends most of time heating. Once the cabin is warm it takes less energy to warm it. Not sure the battery temperature itself had as big of an impact? I do like your idea so next winter I'll have to try it out. The route to the Oakdale Supercharger goes by my office.

Mike UpNorth | 2019年4月12日


Yeah, I guess I should clarify my goal better....I want to be able to get in the car during the winter and have 0 regen limited dots....Efficiency be damned....Speaking of Oakdale - been meaning to take a drive over there and check it out. From the app looks like a busy super charger.

Bighorn | 2019年4月12日

Oakdale usually has spots though you may see some ICEing by HyVee customers. Apparently there's a happy hour there, though I've never looked. Very nice private bathrooms, IIRC.

Halbach | 2019年4月12日

@Roger1, cabin has a resistance heater and that is sole source of heat for the cabin.

Mike UpNorth | 2019年4月14日

Oops, lost track of this thread.

Next time you're through give a shout. Would meet up at Oakdale.....any excuse to drive so I'm going to head there now. Finally going to test out auto lane changes.... TTYL

Bighorn | 2019年4月14日

Albert Lea is permitted for another charger. I visit MSP a couple/few times a year. I’ve met quite a few local owners over the years in other parts of the country.

jjgunn | 2019年4月14日

Something wrong with simply plugging the car in at night at home? During winter?

Battery should be nice & toasty when you drive in the morning.

Mike UpNorth | 2019年4月14日


Nowhere near toasty. More like 0 regen braking in winter.

Bighorn | 2019年4月14日

Plugged in and charging is the key.

jjgunn | 2019年4月14日

I think he needs more than 120v at 12 Amps

Bighorn | 2019年4月14日

Yes, the more kWs, the better.

gballant4570 | 2019年4月14日

In winter I gave the battery a warming charge (an hour or more) before leaving. Also pre-warm the cabin. This approach will never result in zero regen dots though - but it will make the disappearance of those dots happen quicker.

Mike UpNorth | 2019年4月14日

Back to OP.....I'm hoping the 'warm battery in route to super charger' allows for some stationary battery warming... hopefully.

gballant4570 | 2019年4月14日

Mike UpNorth, I think I read that the battery warming process also uses your GPS location from the Super Charger to determine warming start, etc.... I might not be remembering right, but if that's the case it might be hard to fool it.

Mike UpNorth | 2019年4月14日

Agreed @gb