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Battery Coolant

16K views 49 replies 16 participants last post by  GregBrew  
#1 ·
Hello all Bolters. Does the battery cooling liquid only flow through battery chambers when car is running and battery is hot? Does it need car to be running to do so? Does it do anything else?
Thanks.
 
#2 ·
I’m sure some expert can explain it in more detail, but in general an EV is never “off”. Computers monitor the battery temperature at all times and pump to keep the battery warm or cool. It is necessary to keep the battery warm for charging, and cool to avoid battery degradation (think parked in Phoenix in the summer).
 
#4 ·
It will cool or warm the battery whether the car is running or not. It depends on how hot or cold the pack is. But it is more likely to actively cool or heat the battery if the car is plugged in (whether charging or not).

For example, when it is over 90 degrees but less than 100 degrees, and I drive a decent distance and park the car and turn it off, it probably won't actively cool the battery. But if I plug it in (while turned off, not charging), it will start cooling the battery.

If it is over 100 degrees, it will probably start cooling the pack when shut off whether the car is plugged in or not.

It will also cool the pack when driving, I'm just mentioning specific cases when you can see different behavior depending on if the car is plugged in or not.
 
#6 ·
So it is like a coolant basically. So at certain temperatures it will kick itself on whether or not car is actually running. Now what about winter? Can the same fluid be circulated to bring the temperature up? Is the coolant made to not freeze too?
Thanks.
 
#24 ·
You got your answers, but to summarize it :
  • no, the cooling liquid flows all the time
  • no, the car doesn't need to be running so that the cooling fluid could flow
  • yes, it does. It cools or warms up the battery, besides moving around.
 
#34 ·
Glad to hear GM is going to a heat pump in the Ultium EVs. Yeah, heat pumps aren't the only solution to heat in the winter, but if you have an AC system you basically already have a heat pump. May as well put it to use for heating when you can. In areas like where I live a heat pump can make a big difference in driving efficiency. It rarely gets cold enough in KC for them to not be better than a resistive heater.
 
#36 ·
Heating and cooling of the battery may have changed since my 2017, but I think it has been established that the car does not cool or heat itself if it is not plugged in and not on. The car does cool itself if you are using a DCFC in hot weather. The video says it does it too while L2 charging, but I haven't seen it do that.

In Bolts with the settable charge limits, you can set the charge to lower than what the car currently is charged to, plug it in, and it will maintain the battery at about 80 degrees and heat it as well when needed. If the car cools the battery while doing L1 charging, I have not seen it, even when it has been pretty darn warm in the garage. I need to do a little more watching with Torque-Pro though.

I may be wrong and would love if the car would wake up and cool the battery when parked in warm weather but I am pretty sure that isn't the case.
 
#46 ·
I can discuss with limited public relations about how BMW 5th generation propulsion unit is so efficient and how they managed to make two different electric motors in one package, yes PM and AC electric motor capability by nanosecond in software maps change.
BMW doesn't have inefficiency when using AWD like others.
Because BMW propulsion units can be AC or PM motors whatever makes better for efficiency.
Researching PM vs AC motor is needed if someone is interested on more information.
Because it will be very difficult to follow up if I continue.