Reasonable expectations for unthrottled regen?

[GA_Rivian]

Today went ~80 mi (160 round trip) ~30 of which was up and over a pass (4000' - 6000' - 4000'). When I started down from the top, roads were partly snow-packed, so doing ~55mph. Battery 49degF, 53%SOC, motors coolish - 105? and 40?. Regen set to max. Grade ~6deg. After less than 2 minutes the limited regen icon showed up and stayed on for ~7 minutes. I had to frequently touch the brakes to keep from running up on the vehicle in front of me. By the time it came back on the grade had eased up and I was occasionally using the accelerator.

What is a reasonable expectation? This strikes me as way too little regen before throttling. Nothing was hot or cold, SOC was in the mid-range; what's not to like?

When I got home I called roadside; I at least wanted the info downloaded for future reference, but they wouldn't do it unless I opened a ticket. I'm a little reluctant to do that right now (SC is 400mi away); I'd just like not to lose the data. Anyone know approximately how many miles / hours of driving are retained?

I'm having trouble reconsiling this with a trip a year ago down in AZ going over the Mogollon Rim in a snowstorm and having a downhill ride for miles and miles where we regained 14 miles over I'm guessing 1/2 hr. Unfortunately I was still figuring things out, and might not have noticed the regen warning icon. What I do remember is that I never hit the brakes, although there were a few other vehicles on the road.

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[SwampNut]

Open the ticket, it doesn't force you to go anywhere.

 

[CANCERDOC]

Was it possible the front motors were running hot from regen? I think an update a couple months ago would engage AWD in a situation like that. What were the motor temps when the limited regen started? Maybe engage sport mode next time to bring the rear motors into play. Changing the stability control to “reduced” also forces AWD but I wouldn’t do that in wintry conditions.

 

[GA_Rivian]

Was it possible the front motors were running hot from regen? I think an update a couple months ago would engage AWD in a situation like that. What were the motor temps when the limited regen started? Maybe engage sport mode next time to bring the rear motors into play. Changing the stability control to “reduced” also forces AWD but I wouldn’t do that in wintry conditions.

The motors were cool. I didn't write the temps down but front was something like 110 and rear maybe 50.
Mostly I'd like some reference points -- how long have people gotten continuous regen when regen is set to max?

 

[DeafPug]

I took a trip to Colorado last summer in the ‘22 quad R1T and never noticed a reduction in the regen. I had seen lots of reports of this, so I was a little surprised by my experience. This trip even included eastbound on I-70 from Silverthorne to Denver. Except for that one trip, my experience with the R1T is in Kansas, so no long descents to worry about…

 

[No_Name5330]

Personally i get throttled regen every day on my way to work. elevation drops about 2 thousand feet and it gets throttled about a third of the way there.

 

[GA_Rivian]

I took a trip to Colorado last summer in the ‘22 quad R1T and never noticed a reduction in the regen. I had seen lots of reports of this, so I was a little surprised by my experience. This trip even included eastbound on I-70 from Silverthorne to Denver. Except for that one trip, my experience with the R1T is in Kansas, so no long descents to worry about…

Thanks; that's summertime, so may have made a difference. I'm surprised the stretch from Eisenhower tunnel down went ok.

Personally i get throttled regen every day on my way to work. elevation drops about 2 thousand feet and it gets throttled about a third of the way there.

That would match up with what I'm seeing.

Changing the stability control to “reduced” also forces AWD

Thanks, I tried that today and noticed it engaged the rear for regen. I have a repeat of the trip that caused trouble tomorrow and will see if that helps.

 

[edman007]

I would say it's normal, if the battery is below 50F, then it can't do full regen at any reasonable charge level (maybe it can if you're low). Consistent use of regen reduces it further.

I would say if your battery was a lot warmer, or the SoC a lot lower (or both), then it would have been much less of a problem.

 

[rodbrock]

I go the mountains at least 3 times a week. The truck consistently throttles full regen in less than 10 minutes into the descent. It doesn’t matter if it’s summer or winter.

 

[rylcannoneer]

Related situation here. Mine will limit very quickly and even after charging at home sometimes. Battery temps usually around 70F and motor temps between 50F and 110F. SOC between 50 and 70%.

I have a service appointment for it. The tech I spoke to says they haven't seen this issue for a long time, but sounded like they may know what's wrong.

I would put a ticket in and see what they say.

 

[Riviot]

What is a reasonable expectation?

Within spec. Your battery was cold. Get it 70°+ and it'll happily accept more charge. BMS at work.

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