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Cold WX Supercharging: auto heat battery to optimal temperature if supercharger is nav destination

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Supercharging a cold battery results in under 20kW of charge which is impractical for road trips. I think that the car should be smart enough that it heats the battery to a temperature that allows full speed supercharging if a supercharger is the navigation destination.

The range loss from heating the battery would be more than offset by 120kW change rate.

Model S P100D has the "max battery mode" that actively heats the battery for best performance.

All I ask is a UI message that lets us know "battery pre-heating for optimal supercharger speed" so we can know why our efficiency is taking a hit.
 
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This has been discussed a lot in other threads. The Model 3 does not have a separate battery heater like the S and X do, so it can't do any extra heating while you are driving.

Yes it can. The Model 3 can generate up to 4 kW of heat by using the drive inverter to send an inefficient wave form to the electric motor. This results in heat with no propulsion. The drive unit oiling system then picks that heat up and transfers it to the battery coolant loop by way of pumps and a fluid heat exchanger.

It should be possible to incorporate automatic battery heating when the vehicle is being navigated to a Supercharger. Tesla could also/alternatively add a "CONDITION BATTERY FOR CHARGING" button on the charging screen that would do just that - add heat in preparation for charging.

It's in Tesla's best interest to make sure people can get full speed charges in the winter. Reduced charge rates will result in longer Supercharger stops, which will unnecessarily burden the network, especially during holiday travels.
 
Yes it can.
No it can't. Did you bother to read what I wrote?
so it can't do any extra heating while you are driving.
The Model 3 can generate up to 4 kW of heat by using the drive inverter to send an inefficient wave form to the electric motor. This results in heat with no propulsion.
I'm well aware of that functionality, but it can't use that stationary motor winding heating effect while it is having to use those motor windings to drive the car. That's why I gave that specific condition.
 
No it can't. Did you bother to read what I wrote?


I'm well aware of that functionality, but it can't use that stationary motor winding heating effect while it is having to use those motor windings to drive the car. That's why I gave that specific condition.

I read what you wrote. You posit that it can't make heat while driving. It's just a matter of driving the motor with a slightly less efficient wave form to generate more waste heat in the propulsion process, and voila - battery heat.
 
I read what you wrote. You posit that it can't make heat while driving. It's just a matter of driving the motor with a slightly less efficient wave form to generate more waste heat in the propulsion process, and voila - battery heat.
"less efficient waveform" Are you sure that's a thing with how the motors actually work? I thought for them to operate, they need to have their correct synchronization and not anything else.
 
Looking through Ingeneerix's video here:


Some interesting notes:

At 4:27, you'll see a field labeled ETH : BMS_powerStationaryHeatPower
At 6:53, you'll see a field labeled ETH : BMS_inletActiveHeatTargetT

This leads me to conclude that you're right, @Rocky_H - the motor can only do battery heating when stationary. Also, the BMS won't call for battery heat until -7.5C, although that can probably change depending on certain conditions like plugging into a Supercharger or maybe in the future with my desired "condition battery for charging" function.
 
Some interesting notes:

At 4:27, you'll see a field labeled ETH : BMS_powerStationaryHeatPower
At 6:53, you'll see a field labeled ETH : BMS_inletActiveHeatTargetT

This leads me to conclude that you're right, @Rocky_H - the motor can only do battery heating when stationary. Also, the BMS won't call for battery heat until -7.5C, although that can probably change depending on certain conditions like plugging into a Supercharger or maybe in the future with my desired "condition battery for charging" function.
That did seem to make more sense with how I thought the motors would work. That -7.5C is pretty interesting. That does seem really low to call for that, and I agree with you, that there should be some other ways, (either with or without user interaction) to detect or call for using that active heating while the car is parked, when you know you're going to want the battery warmer for Supercharging.
 
I really wish someone like Ingineerix would try to determine what exactly the car does to try to maintain the battery temperature (both heating and cooling) under different conditions. and then share with the rest of us of course.

A lot of articles and conversation on here seem to assume that the 3 works the same as the S and the X, but we know that can't be true because they don't have the same plumbing and heater setups. I think a lot of people assume they know how it works, but I don't recall seeing much actually confirmed by Tesla.
 
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