Model 3 Battery Heating?

[taraquin]

I don’t know if it going to get as low tonight but I am leaving car outside and will check in morning

Have you had time to test it? Interesting to see

 

[diamond.g]

Have you had time to test it? Interesting to see

It wasn’t cold enough. Will try again later this week as the lows will be around freezing.

 

[Big Earl]

If track mode can dump the AC through the battery coolant loop radiator is there any reason they couldn't redirect the cabin heater air through the coolant loops radiator as well? Would be a very large drain to run that wide open when you are driving but seems like something that might make sense when plugged into a supercharger.

The reason that won't work is because the cabin heater is a PTC heating element with no liquid heater core. It's basically a big hair dryer. There is no way to redirect this heat to the battery pack.

The motor(s) are capable of heating the battery pack ... Tesla just has to get more aggressive with their programming. I think they're trying to do as little heat as possible in order to maximize efficiency and range. I expect future software updates will get the heating algorithms dialed in.

 

[brur]

if you are interested in tesla's M3 batteries. cooling/heating et al

 

[Big Earl]

if you are interested in tesla's M3 batteries. cooling/heating et al

That's a helpful video, but the part about harnessing waste heat to heat the cabin is misleading. While Tesla has filed a patent, no Tesla vehicles currently produced can direct waste heat from the electronics into the cabin. Doing so would require a liquid heater core in the cabin, which no Teslas have. So far, waste heat can only be shed through the radiator or sent to the battery back.

 

[brur]

B Earl, I assumed the heat was coming from the electronics that are part of the battery system/ motor motivation. Not from the cabin heat

 

[Big Earl]

B Earl, I assumed the heat was coming from the electronics that are part of the battery system/ motor motivation. Not from the cabin heat

He talks about several things in the video. I'm addressing the specific comment about taking waste motor/inverter/electronics heat and directing it to the cabin, which is currently impossible. Video timestamp is 15:03.

 

[SigNC]

The reason that won't work is because the cabin heater is a PTC heating element with no liquid heater core. It's basically a big hair dryer. There is no way to redirect this heat to the battery pack.

The motor(s) are capable of heating the battery pack ... Tesla just has to get more aggressive with their programming. I think they're trying to do as little heat as possible in order to maximize efficiency and range. I expect future software updates will get the heating algorithms dialed in.

Couldn't you just dump it through the radiator? Granted it's highly inefficient but I just meant in scenarios where you are supercharging very slowly due to a cold pack.

 

[Big Earl]

Couldn't you just dump it through the radiator? Granted it's highly inefficient but I just meant in scenarios where you are supercharging very slowly due to a cold pack.

The radiator goes to the atmosphere. I'm not sure how that would heat anything other than the great outdoors.

 

[SigNC]

inverse of how cool air through a radiator cools the coolant

 

[MP3Mike]

Couldn't you just dump it through the radiator? Granted it's highly inefficient but I just meant in scenarios where you are supercharging very slowly due to a cold pack.

To get the heat from the PTC heater to the radiator you would have to heat the outdoors. So no, that isn't going to work.

 

[MP3Mike]

inverse of how cool air through a radiator cools the coolant

The PTC is in the cabin and heats air in the cabin. The radiator is outside in the frunk. You can't get the PTC heated air to the radiator. (Though maybe you could run the cabin fan backwards to get airflow in the general direction? )

 

[Big Earl]

inverse of how cool air through a radiator cools the coolant

Let's start from the beginning regarding cabin heating.

1.) The cabin heater is a resistive heating element. There is no connection to the coolant loop that heats/cools the battery, motors and electronics. Heat from the cabin heater can't go anywhere but to the cabin.
2.) The radiator is connected to the battery, motors and electronics for dumping heat during cool weather when the air conditioning compressor isn't required. Heat from the battery, motors and electronics cannot go anywhere but the radiator or the air conditioning condenser (the radiator's twin) by way of the refrigerant system.

 

[SigNC]

Fair enough, I was just speculating if there was piping to redirect the hot air to the radiator. Clearly that is not the case.

 

[UltralightBeam]

Okay... so long story short right now is that preheating the cabin ONLY warms up your cabin. That’s it. So you really only need it to be on for a little bit for comfort... IE in 20 degree F weather, it takes about ten minutes to get comfortable at around 70ish.

I’ll still have a huge amount of regen unavailable to me no matter what unless there’s a “battery heater” update pushed?

 

[SigNC]

I don't particularly care about the reduced regen as much as I would like the ability to crank up the inefficiency of the motor 10-15 miles before I get to a supercharger.

 

[Jaywlker]

Drawing power to heat the cabin also warms the battery right?

Turning on the cabin heater does not directly warm the battery, but it does draw current from the battery, indirectly warming the battery pack because of the current draw, but your Tesla can also warm its batteries directly with its battery heater if ambient temperatures are sufficiently cold.

 

[SigNC]

Turning on the cabin heater does not directly warm the battery, but it does draw current from the battery, indirectly warming the battery pack because of the current draw, but your Tesla can also warm its batteries directly with its battery heater if ambient temperatures are sufficiently cold.

Just to summarize what has been discussed in the 3 forum about this as this is the 3 forum. There is no dedicated pack heater and the target battery temp to where an inefficient wave is sent to the motor to produce excess heat, currently, seems fairly low. This has resulted in fairly cold batteries arriving at superchargers.

 

[taraquin]

Just to summarize what has been discussed in the 3 forum about this as this is the 3 forum. There is no dedicated pack heater and the target battery temp to where an inefficient wave is sent to the motor to produce excess heat, currently, seems fairly low. This has resulted in fairly cold batteries arriving at superchargers.

Still haven`t heard what regen people actually get when batteryheating stops In the Model S, I get around 30kW regen and then the batteryheater stops. It would be interesting to see what kind of regen\battery-temp Model 3 has when heating stops

 

[Big Earl]

Still haven`t heard what regen people actually get when batteryheating stops In the Model S, I get around 30kW regen and then the batteryheater stops. It would be interesting to see what kind of regen\battery-temp Model 3 has when heating stops

So far nobody has reported a Model 3 actually heating the battery, so nothing to report.