Battery percentage does not match predicted milieage

[sjg]

I let my R1T update to 2024.27.01 last night. The vehicle was parked with 70% state of charge. I let it update overnight. The R1T wqs plugged into the Rivian wall charger but it had charged to the 70% limit several hours before I started the update.

When I woke up this morning my said 70% of charge but then incrementally grew to 93% state of charge in a matter of seconds. I went to the vehicle. The display behind the steering wheel said 93% with 212mi of range. I did a software reboot and two hard reboots. Each time the % charge started near 70% and then climbed real time up to 93%.

With 212mi of reported range, that comes close to a 70% charge (212/0.7=303mi at 100%). A 93% charge and 212mi of range is only (212/0.93=228mi at 100%). I have 21" wheels and average about 2.2mi/kW.

Has anyone else seen this strange behavior after the update.

Steve

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[usulio]

Maybe you got software downgraded to Large+.

Did you try a reset yet?

 

[CANCERDOC]

Maybe the battery just needs to be recalibrated. Maybe drive it down close to 20 and do a full charge to 100 to see if the battery monitor "relearns."

 

[CANCERDOC]

Maybe you got software downgraded to Large+.

Did you try a reset yet?

OP said they did 2 hard reboots.

And its 27.01, so its a Gen 1, no large+.

 

[sjg]

I have a mobile service scheduled. It won't be until next Thursday. We'll see if it resolves itself by then. Until then I'll just have to decide if I want to follow the reported mileage left or the reported state of charge. Following the mileage should be more conservative.

 

[sjg]

Here is a video of what I see when the R1T wakes after sleeping for a long time. The battery % just keeps climbing.

https://www.icloud.com/photos/#/icloudlinks/049UTpGBWRt1Gvj9nXndWca7Q/0/

 

[cbrcanuck]

Yikes, that would be concerning if I had a road trip coming up! Please report back when solved, I'll be watching this one.

 

[sjg]

Rivian mobile service is coming on Thursday 22-Aug. I'll update this post after that.

 

[Mathme]

does the % on the dash do that or is it just in the app?

 

[sjg]

Both the app and the vehicle behave the same way. Immediately after waking from sleep the % is correct. Then it climbs to about +20% over the next minute.

 

[sjg]

The mobile technician just left. He said that they had a good idea of what the issue was because of the logs that were sent to Rivian when I did the hard reboots (flashers + steering wheel left button). He made the trip so that they could plug into my vehicle directory to see if the same codes persisted or if they were transient in nature. The same errors codes persisted when he plugged in locally.

The technician does not believe that my issue had anything do do with the software update. It was merely coincidence. The error codes they are seeing report a "battery cell voltage imbalance". I guess this happens when some of the cells are not at the same voltage levels as the others. He said this can happen even if the delta is only a few millivolts.

The typical corrective action for this item is a battery pack replacement. He said they will take it to the shop and do further diagnostics but the end result is likely the same. The battery is still under warranty so it is no cost to me. Once the order for a battery is placed, he said it only takes 2-3 days to get one to Austin.

I do have to take my running boards off again since they will be removing the under body plastic panels and such.

 

[blindmikey]

A free battery replacement doesn't seem like too bad of an ending!

 

[cbrcanuck]

Thanks for the update! Frustrating to deal with, but nice to have a definitive answer and action plan.

 

[sjg]

I've updated the post title since the issue had nothing to do with the software update. It was coincidence.

My R1T has been at the service center for about a week. They did additional testing and confirmed they wanted to swap out the battery. I did not get any additional details about what the battery error codes were or what they think caused some cells to be a slightly different voltage than others.

The order for a batter pack has been placed. It will come from Normal, IL to Austin, TX on a flatbed truck. They say it weighs about 1800lbs. I expect they will be able to install it sometime this week.

This time they actually gave me a R1T loaner instead of an Enterprise car. It was a nice option... until I got a flat tire and the loaner did not have a spare. Luckily a good samaritan with a plugging tool was able to successfully plug the tire. I was surprised because of the size of the hole and the need for ~50psi. We drove over 30mi on the plug and it held fine. Rivian service sent a mobile van to our house the next morning to swap out the tire for a new one.

 

[sjg]

Rivian sent a battery pack from Normal, IL to Austin, TX. They replaced my battery pack. In total, they had my vehicle for about 1.5 weeks.

Steve

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