Yikes! Overheating motors.

[Zoidz]

Read OP’s follow up post, man. The bar turning reddish is NOT over limit indicator. The red hash marks is that limit, which his vehicle did not reach. It did not overheat. Period.

I suppose the bar turning reddish is part of the Halloween theme? The bar turning red is a warning indicator. Period. Get over it.

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[emoore]

Jeez. “Dramatic characterization”? I had to laugh. Give me a break. I just reported exactly what happened. Get over it, dude.

Did the motors overheat?

 

[mindstormsguy]

I suppose the bar turning reddish is part of the Halloween theme? The bar turning red is a warning indicator. Period. Get over it.

Right, because warning indicators are usually hidden on the infotainment on a screen that is entirely optional to browse to, instead of on the instrument cluster where this "critical" piece of information would be impossible to miss.

The red bar is a UI issue - that's all. Some UI designer asked "what's the expected temperature range for the motors?" Some engineer replied with the nominal operating range, and then the UI designer put the red mark at the top of that. It was poor internal communication, that's all.

There have already been a handful of posts across the internet showing this exact same behavior. The truck heats the motors up when it's cold outside and it wants to warm itself up.

 

[Zeus]

Here comes the doom and gloom articles by "journalists" (read vouyers) who spend an inordinate amount of time on EV forums: "Rivian owners report overheating motors!"

 

[zefram47]

FWIW, my battery started out at 50F this morning (garage parked, 16F outside). On the drive into work I saw just under 100F on all 4 motors and a small amount of regen blocked off on the gauge (maybe 20%). If this is the result of using the motors to warm the pack, I wonder what the magic temperature is that they decide to do this. I did precondition the cabin for about 15 min before leaving, so no clue what happened prior to getting in...but it was a little odd the motors were so much warmer than the battery when I left.

 

[R.I.P.]

FWIW, my battery started out at 50F this morning (garage parked, 16F outside). On the drive into work I saw just under 100F on all 4 motors and a small amount of regen blocked off on the gauge (maybe 20%). If this is the result of using the motors to warm the pack, I wonder what the magic temperature is that they decide to do this. I did precondition the cabin for about 15 min before leaving, so no clue what happened prior to getting in...but it was a little odd the motors were so much warmer than the battery when I left.

Not odd at all.

The motors have much more capacity to heat themselves than the battery does, and are far less mass.

 

[MountainBikeDude]

So, I went out for another drive, just now. Pretty much the same scenario as before - cold night, current day temp in mid-40’s. Drove roughly the same distance, terrain and speed. This is what I got after about 7-8 miles. On the driver’s side, front motor, shortly after peaking out at 271 degrees, just shy of the red line, the motor temps dropped pretty steadily back to the normal range. This time I did not reduce the regen level, keeping it on high regen. I might also add that the vehicle efficiency was way down. I’m averaging around 2.8m/kWh over the last 1000+ miles. During these last two events, I was under 1.6m/kWh. I do realize the cold weather and cold battery didn’t help, but that was quite a drop.

Mine has done the exact same thing. Same front left motor in the orange, and others still grey, but similarly toasty. I posted it elsewhere to help another user sleep at night.

It raises the motor temps in the same fashion until my pack temp got to 12C (Canadian Maple Syrup units) from that temp onward, all motor temps immediately cooled down to around 20-30 degrees C.

Nothing abnormal.

 

[Dark-Fx]

FWIW, my battery started out at 50F this morning (garage parked, 16F outside). On the drive into work I saw just under 100F on all 4 motors and a small amount of regen blocked off on the gauge (maybe 20%). If this is the result of using the motors to warm the pack, I wonder what the magic temperature is that they decide to do this. I did precondition the cabin for about 15 min before leaving, so no clue what happened prior to getting in...but it was a little odd the motors were so much warmer than the battery when I left.

Start of my drive this morning:

Three minutes later when I finally got out of my subdivision. 25 mph speeds.

I didn't take any more photos this morning but the temps creeped up until the first motor hit orange at 54F battery temp, then they all plummetted back down into the low 100s. Guessing the threshold for starting this process is < 50F based on your observation and mine. I did no preconditioning and the motor temps fell every time I was at a complete stop.

I did perceive the motor noise to be somewhat different while this process was ongoing and I was traveling at a low rate of speed. But entirely possible it's just observation bias.

 

[docwhiz]

I think this might be a case of "too much information".
While I think it is nice to have this information available. It seems to serve no useful purpose.
What is the driver supposed to do (besides panic) if the information shows orange or red temperatures? It doesn't seem like the car issues any warnings such as "slow down" or "stop driving".
I would think that if there was really an "overheating" problem that the car would automatically take care of the problem without inconveniencing the driver (or at the very least put up some kind of explanation message).

 

[R.I.P.]

Warm components, including electric motors, run more efficiently. In an ICE there is a thermostat that does not allow coolant to circulate until components have warmed to an operating temperature. You want your engine, transmission and running gear to be warm.

It makes complete sense that cooling would not be kicked in until your motors are nice and toasty and actually need some cooling. The temperatures we are talking about here are perfectly normal and within intolerances for an electric motor.

 

[Dark-Fx]

It makes complete sense that cooling would not be kicked in until your motors are nice and toasty and actually need some cooling. The temperatures we are talking about here are perfectly normal and within intolerances for an electric motor.

I don't think that's what this behavior is at all. On drives where the battery is "warmer" I haven't seen anything above maybe 160F from doing repeated hard take offs and full regen at the next stop light. Easy driving today and limited regen and still saw every motor get to 250F before cooling off.

Will be interesting to see what the difference is when it's actually legitimately cold out (like -10F and below)

 

[COdogman]

Since we've had access to this data I don't think I've seen my motor temps get above 170 yet, even with some spirited driving. Maybe I just wasn't looking when it was higher.

 

[Dark-Fx]

Since we've had access to this data I don't think I've seen my motor temps get above 170 yet, even with some spirited driving. Maybe I just wasn't looking when it was higher.

You're just not driving cold enough

 

[MountainBikeDude]

My drive the other day.

So, I went out for another drive, just now. Pretty much the same scenario as before - cold night, current day temp in mid-40’s. Drove roughly the same distance, terrain and speed. This is what I got after about 7-8 miles. On the driver’s side, front motor, shortly after peaking out at 271 degrees, just shy of the red line, the motor temps dropped pretty steadily back to the normal range. This time I did not reduce the regen level, keeping it on high regen. I might also add that the vehicle efficiency was way down. I’m averaging around 2.8m/kWh over the last 1000+ miles. During these last two events, I was under 1.6m/kWh. I do realize the cold weather and cold battery didn’t help, but that was quite a drop.

My drive the other day. Didn't hit the orange on that occasion as battery temps had leveled off prior. This was over 13 minutes of driving. Neat to see how things work, but nothing that's concerned me.

 

[COdogman]

You're just not driving cold enough

We have been enjoying February in October for the past few days and it was a balmy 14 degrees this morning during my 20 mile highway drive to work. I was actually watching those numbers and while they did warm up over the course of the drive, they were only about 160 by the time I arrived.

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