Sudden Battery Capacity Loss

[Electrified Outdoors]

Wow, that will certainly get your attention on a road trip!

I have not seen this issue before. If there is a problem with battery cells it should trigger an alert in the BMS that you need service. My video shows how to access the RIDE menu, your looking for dashboards>BMS and that will give you some more insight. including your SOH and voltages.

Running it down close to zero and charging it to 100% might be a good test. Your battery back is actually 141 kwh with 131 kwh usable. When initially released the R1 had a lower usable capacity (around 126 kwh) which lead to many folks referring to it as a 125 kwh or 135 kwh battery. Later on, Rivian opened up more usable capacity for large pack.

Any way to post some video or pics of what your seeing on your end?

Sponsored

 

[OnePedaler]

That's exactly when you Should view it and take a pic, it'll show actual charge and capacity and will help troubleshoot.

Hi @OnePedaler, were you estimating the reduced battery capacity based on the DCFC display of how much energy has gone in or the truck’s “energy” display? Or do the two agree approximately?

As far as I know, this is the first time anyone has posted this kind of issue(sudden capacity loss). An odd and maybe concerning thing about your issue is that the battery seems to have lost half the capacity suddenly without diagnostic or fault messages showing up.

good luck to you and I hope service can get you back up to full range.

Yes, my calculations compare what the charger says it delivered and what the R1S displays. That’s realization made us aware that it was “real” and not just a display glitch. What backed this up is our efficiency has been stable and what one would expect for ideal driving conditions. Today again we are on flat road (Interstate 74 in Illinois) and 59 deg F and sunny. Minimum wind.

I’ll report back to all once it’s diagnosed at Service Cemter this coming week in Cincinnati.

 

[OnePedaler]

Wow, that will certainly get your attention on a road trip!

I have not seen this issue before. If there is a problem with battery cells it should trigger an alert in the BMS that you need service. My video shows how to access the RIDE menu, your looking for dashboards>BMS and that will give you some more insight. including your SOH and voltages.

Running it down close to zero and charging it to 100% might be a good test. Your battery back is actually 141 kwh with 131 kwh usable. When initially released the R1 had a lower usable capacity (around 126 kwh) which lead to many folks referring to it as a 125 kwh or 135 kwh battery. Later on, Rivian opened up more usable capacity for large pack.

Any way to post some video or pics of what your seeing on your end?

Thanks much for the battery info and video “how to”. We look forward to getting this issue resolved!

 

[Throwdown]

Yes, my calculations compare what the charger says it delivered and what the R1S displays. That’s realization made us aware that it was “real” and not just a display glitch. What backed this up is our efficiency has been stable and what one would expect for ideal driving conditions. Today again we are on flat road (Interstate 74 in Illinois) and 59 deg F and sunny. Minimum wind.

I’ll report back to all once it’s diagnosed at Service Cemter this coming week in Cincinnati.

If it isn't a software glitch where the range calculation is just off I'd bet that one of your cell modules is way out of balance(low) and its bringing the total capacity of the battery down to its level- for example for whatever reason one of the models is only at 50% of its total capacity so now the total capacity of the battery is only 50% even with a full charge. I have seen that happen with other evs and curiously didn't throw a fault. Has it ever had a battery repair or any battery issues?

 

[OnePedaler]

If it isn't a software glitch where the range calculation is just off I'd bet that one of your cell modules is way out of balance(low) and its bringing the total capacity of the battery down to its level- for example for whatever reason one of the models is only at 50% of its total capacity so now the total capacity of the battery is only 50% even with a full charge. I have seen that happen with other evs and curiously didn't throw a fault. Has it ever had a battery repair or any battery issues?

Interesting to see your perspective! No, we have not a battery repair or any issues in the past. But, strange no faults.

However, our Nav system is having a hard time with this. It isn’t calculating the time for charging correctly. It is severely underestimating the time for charging. Giving us 7 min or at the most 13 min estimates for charger stops. And the Nav system is continually updating the route because we are so close to the edge when we stop.

 

[Throwdown]

Interesting to see your perspective! No, we have not a battery repair or any issues in the past. But, strange no faults.

However, our Nav system is having a hard time with this. It isn’t calculating the time for charging correctly. It is severely underestimating the time for charging. Giving us 7 min or at the most 13 min estimates for charger stops. And the Nav system is continually updating the route because we are so close to the edge when we stop.

I expect no faults initially depending on how hard it tries to balance the cells and when it decides to do so. Given that it's showing fast stops really indicates that the overall capacity is severely diminished. I would keep doing what you are doing for sure, keep assuming that you only have half of what it should have until you can get it looked at.

 

[Riviot]

Interesting to see your perspective! No, we have not a battery repair or any issues in the past. But, strange no faults.

However, our Nav system is having a hard time with this. It isn’t calculating the time for charging correctly. It is severely underestimating the time for charging. Giving us 7 min or at the most 13 min estimates for charger stops. And the Nav system is continually updating the route because we are so close to the edge when we stop.

 

[Electricnewbie]

Our battery capacity has dropped in half as measure in miles at full charge in all drive modes on our R1S. Purchased in Aug 2023. Last 5 numbers of VIN 13736. Large Pack battery. Quad motor. So battery capacity is nominally 125 kw. We have all recent vehicle updates complete.

We noticed the problem since about Feb 10 in around town driving. We had to home charge each night instead of every couple days.

Now we are on a road trip with good weather (50-70 degree F), no wind and pretty flat on Interstate 90 from SD to IL. Going 65 mph. After 810 miles of driving our Trip A records 2.23 mi/kw in Conserve mode. This should translate to around 275 miles of full battery range (which we have achieved in similar conditions on past trips).

But, we get only 150 miles when we charge the battery to full amount. We switched to All Purpose for about 50 miles and didn’t see any difference. So we are stopping every 120 miles to charge up to 70-85% which gives us only around 125 miles range.

We called Service and tried to reset History on Energy screen tab, soft reset, hard reset and sleep cycle of 5 hours. Still have the problem. We do have an appointment with Cincinnati Service Centwr on March 5.

So basically getting good efficiency but limited range. Any help or suggestions our there??

Hello OnePedaler;
I’m having the exact issue on my R1T (Quad motor) 13762 at 36k miles. I can only achieve 140 miles from a full charge (320) and roll into the charging station with 40<> miles remaining on open flat road not towing.
My service appointment is March 7th and will share feed back.
Oddly around town and short tripping I can achieve 220-280 (most likely thanks to re-Gen), but the steady state discharge of highway driving and not lifting is a nemesis at this point.

 

[Polar]

Hello OnePedaler;
I’m having the exact issue on my R1T (Quad motor) 13762 at 36k miles. I can only achieve 140 miles from a full charge (320) and roll into the charging station with 40<> miles remaining on open flat road not towing.
My service appointment is March 7th and will share feed back.
Oddly around town and short tripping I can achieve 220-280 (most likely thanks to re-Gen), but the steady state discharge of highway driving and not lifting is a nemesis at this point.

What’s your average speed mate? Any head winds? Roof box?

 

[Electricnewbie]

No roof box, a bi-directional run on the same day. 74mph on cruise control, payload <300#, bed covered, tire pressure 44psi, avg head and tail wind 5-7mph.
The same run 2 months prior 245 miles attained with 35 remaining when I stopped to charge (280 actual range).

The two trips mentioned were both in all purpose.

I did try once in ECO as it was disastrous, I only achieved 120 miles and had to charge.
Good thing I didn’t have matches ?

 

[HaveBlue]

In tow mode the percentage state of charge should still be accurate. Only the range should vary. Percent state of charge should be based on the voltage of the pack but is probably adjusted by battery health as the resistance increases on a defective pack.

 

[OnePedaler]

Hello OnePedaler;
I’m having the exact issue on my R1T (Quad motor) 13762 at 36k miles. I can only achieve 140 miles from a full charge (320) and roll into the charging station with 40<> miles remaining on open flat road not towing.
My service appointment is March 7th and will share feed back.
Oddly around town and short tripping I can achieve 220-280 (most likely thanks to re-Gen), but the steady state discharge of highway driving and not lifting is a nemesis at this point.

Our VIN are similar timing! I hate to say it but glad we are not alone. What SC are you going to? I’ll mention it to the Cincinnati SC on our appointment on March 5. Let’s hope we both get a good resolution.

 

[Electrified Outdoors]

Would be helpful if both of you could post photos of what your seeing in the trip screen for efficiency, energy screen estimated range, energy screen tap drive mode will show estimated range on full charge, and what shows in the RIDE menu under BMS. It would be helpful to anyone else who may encounter this issue.

 

[OnePedaler]

Take a look at a screen shot at the end of road trip last night showing excellent efficiency. And a screen shot of the estimated full range for all modes. Our range had been 305 miles for Conserve mode and 275 mile for All Purpose in the past but no screen shot. (We sent to SC). We didn’t do the RIDE screen since service appointment is close and we will see what they find out. (And we are chicken!)

 

[Electrified Outdoors]

Take a look at a screen shot at the end of road trip last night showing excellent efficiency. And a screen shot of the estimated full range for all modes. Our range had been 305 miles for Conserve mode and 275 mile for All Purpose in the past but no screen shot. (We sent to SC). We didn’t do the RIDE screen since service appointment is close and we will see what they find out. (And we are chicken!)

Thank you for this. This is definitely to be an educational post for sure. I know you're on a road trip, but if you get a chance to go into the ride menu I will be really curious to see what the BMS dashboard says.

Also, are you seeing any power limitation once you've used about 3/4 of the range? Once you get below 10% remaining it should show you limited. Acceleration in the dryers display. If you truly have only half of your capacity available then you should see that at a higher state of charge I would think.

You would need to put it back in all purpose mode though because the conserve mode will always show limited power due to the two-row motors being disabled.

Sponsored