General interest - when fast charging (RAN), motor temps increase.

[KRo]

Something I noticed this morning when picking up some juice from the Clackamas, OR RAN charger this morning… I swapped over to the gauge display right after starting a charge to see how quickly the motor temps would drop toward the ambient temp (39 degrees) … and the opposite was happening. Motor temps were actually INCREASING, which I found curious. Motors topped out around 220-230 degrees, one hitting 256.

So, my take would be, the temp sensors displayed are not the actual motors themselves… but I found it curious, and others may as well. Short video clip attached to show the event.

BTW, roughly five mins after I took this video, motor temps dropped rapidly toward 100 degrees for the remainder of my charge.

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[R.I.P.]

Something I noticed this morning when picking up some juice from the Clackamas, OR RAN charger this morning… I swapped over to the gauge display right after starting a charge to see how quickly the motor temps would drop toward the ambient temp (39 degrees) … and the opposite was happening. Motor temps were actually INCREASING, which I found curious. Motors topped out around 220-230 degrees, one hitting 256.

So, my take would be, the temp sensors displayed are not the actual motors themselves… but I found it curious, and others may as well. Short video clip attached to show the event.

BTW, roughly five mins after I took this video, motor temps dropped rapidly toward 100 degrees for the remainder of my charge.

When you stopped to charge, the cooling system was turned off. The heat stored in the components transfered to the static coolant, causing the rise you saw.

You should see a rapid decrease as soon as you turn the truck back on and the coolant starts to circulate again.

 

[jjswan33]

Is it odd that it shows the motor temps while charging but not the battery temp?

 

[FooF]

My guess is they are trying to heat the batteries and it is on same loop as motors. Not sure why they would hide battery temp.

 

[Dark-Fx]

Is it odd that it shows the motor temps while charging but not the battery temp?

Rivian doesn't want people calling saying their battery is on fire. It's for sure redlining and maxing out during a RAN charge.

I think they use the motors to generate additional heating for the battery. I saw the same thing driving to work when the battery was cold, motor temps went up to 260+ for a while before leveling off and eventually dropping down to the 140s. Typically I don't see above 140F on a normal warm weather drive.

 

[KRo]

Interesting you saw similar behavior when cold also. My vehicle/battery was also cold, ambient temp 39 degrees as mentioned before. Drive is slightly downhill from my house, drive is nearly exactly a mile to the RAN charger (yes, I'm proximity spoiled, lol) ... so not much acceleration or even regen to get things heated up before the charge.

Overall, I found it as a curiosity, and it's interesting to try and decipher the data.

 

[R1Tom]

Interesting you saw similar behavior when cold also. My vehicle/battery was also cold, ambient temp 39 degrees as mentioned before. Drive is slightly downhill from my house, drive is nearly exactly a mile to the RAN charger (yes, I'm proximity spoiled, lol) ... so not much acceleration or even regen to get things heated up before the charge.

Overall, I found it as a curiosity, and it's interesting to try and decipher the data.

I would really love to see more readings. A system schematic on a screen. Pump speed. Fan speed. Heating element operation, etc... I love knowing how everything is working and when.

 

[MountainBikeDude]

Yesterday I went to charge, battery was at 11 degrees celcius. Plugged in, motor temps went into to the orange (not red) to bring the battery up to temp for fast charging as it only was pulling 31kW. After a couple minutes, the motor temps dropped back to 30 degrees Celsius, and DCFC speed kicked up to the chargers max of 80kW.

I've never seen the battery temps go beyond 25 degrees celcius even with DCFC, but it's been cold lately, and I haven't pushed the systems capabilities while charging beyond 80kW since the update.

Speaking with an employee, he said prior to the update, he would see around 38 degree battery temps when pushing 200kW DCFC. Likely seeing this through the RiDE app.

 

[SeaGeo]

Speaking with an employee, he said prior to the update, he would see around 38 degree battery temps when pushing 200kW DCFC. Likely seeing this through the RiDE app.

The batteries definitely get hotter than 38F when DCFC charging.

 

[diehlryan]

I saw my motor temps rocket up when the truck started to precondition on the way to a RAN. Didn't last super long but it was from 140-260ish in a blink of an eye right as it kicked on.

 

[Zoidz]

The batteries definitely get hotter than 38F when DCFC charging.

I believe he was referring to Celsius temperatures.

 

[MountainBikeDude]

The batteries definitely get hotter than 38F when DCFC charging.

Celsius, not freedom units. And yeah I know from Kyle they push into the low 50C range.

Also, further to my earlier post about motors used to heat the batteries. Was just driving downtown Vancouver. Thermals obviously low and regen/motor output limited warning came up due to cold pack 10C. Once it got past 12C, motor thermals dropped. In any case you get a real sense for how much time is required to bring up, and down pack temps because of the batteries size.

Also noticed a 5% thermal disparity between the left front motor and the front right. Could just be the coolant loop, but interesting since the rear motors are dead even.

One user mentioned this may be the reason for a slight pull to one side when driving, but this hasn't been the case for me. Drives straight and true without intervention from me to correct, obviously road crown dependent.

 

[KRo]

One user mentioned this may be the reason for a slight pull to one side when driving, but this hasn't been the case for me. Drives straight and true without intervention from me to correct, obviously road crown dependent.

THIS is VERY INTERSTING to me, and hadn't seen this mentioned before! My R1T tracks straight as an arrow (sans road crowns were applicable) ... however sometimes a phantom 'pull to the right' (driver aids turned off) will occur and last for a period of time, then go away. Because of this, I've had two alignments performed by Rivian and an investigation into my suspension to make sure all is tight and secure (always passes with flying colors). Definitely a subject for another thread, but I hadn't heard about this possible symptom cause.

 

[MountainBikeDude]

THIS is VERY INTERSTING to me, and hadn't seen this mentioned before! My R1T tracks straight as an arrow (sans road crowns were applicable) ... however sometimes a phantom 'pull to the right' (driver aids turned off) will occur and last for a period of time, then go away. Because of this, I've had two alignments performed by Rivian and an investigation into my suspension to make sure all is tight and secure (always passes with flying colors). Definitely a subject for another thread, but I hadn't heard about this possible symptom cause.

Not trying to create something from nothing. One user just happened to mention the temperature disparity they think could be a larger issue relating to their alignment/motor synchronization. Again, this is an assumption on that user's part, and my temp disparity kinda does away with that theory as mine isn't exhibiting that behavior.

 

[SeaGeo]

I believe he was referring to Celsius temperatures.

I was too... Brain fart. Think more like 50C.

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