L2 charger down to 2.7kwh at 24F.. Should I be worried?

[mkhuffman]

Gen 2 Large is just a Max pack with fewer modules.

Basically - not LFP. Makes sense. Same batteries, just fewer of them.

I thought maybe the larger number of modules could be impacting charging speed. Obviously not.

Personally I probably won't experience the issue very often, and never when parking at home. But when away from home in the winter, like when I commute to my office, I will have to deal with it. I hope the OTA update you referenced fixes this.

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[COMtnEV]

Did my first L2 charge after upgrading software to 2025.06.30. As described below, it was a little disjointed with some confusing results, so can't draw any final conclusions. Some good, some bad.

The truck had been driven about 10 miles prior to starting the charge session at 14% SOC. ABRP battery temp 47.8F, Rivian battery temp 45F, motor temps 59/48 (front/rear). Ambient temp mid-30s. Charged for about 6 hours to 50% SOC with battery warming 0.5F/hr (48.2F), but motors warming more 66/60. Over the next hour, ABRP battery temp jumped to 55F, with motors to 68/62, and temp stayed there for another hour or so (61% SOC). When I next checked, ABRP battery temp had dropped back to 48.2F (68% SOC). Motors remained at 68/64. ABRP temp stayed at 48.2F with multiple syncs over the next 20 minutes. Since it was 1130PM and I was very confused, I stopped the charge at 70%. I checked the Rivian battery temp when charging stopped (50F), which was strange since it is usually 3-5F lower than the ABRP temp on my truck. A minute later, after stopping the charge, ABRP synced again, and was back to 55F. I have no idea what is going on with the ABRP temp readings.

I restarted the charge this AM, Rivian batter 41F, ABRP battery 46.4F, motors 39/35, SOC 70%. Charged steadily to 81% (2 hours) at Rivian 9.3kW. Battery only warmed to 47.5F, motors 46/44. At 81%SOC, experienced my standard throttle to Rivian 7.5kW. At 87%, experienced the my next standard throttle to Rivian 3.5kW (battery 48.2F, motors 51/50).

Initial indications are:
1 - THE BAD The new software does not help when trying to "top up" a cool battery. Warming rate hasn't appreciably changed.
2 - THE HOPEFUL There may be an indication of more aggressive warming with a deeper charge, but there may also be an issue with the validity of ABRP temperature data. Needs more testing.

One additional observation:
3 - THE CURIOUS My charger allows me to vary output in one amp increments. The initial throttle to 7.5kW matches 32A output. The 2nd throttle to 3.5kW matches 16A output. I find it interesting that the throttle steps match standard charger output options (every 8A).

 

[SSFC5]

Upcoming software update 2025.10 looks to be fixing this issue! From the notes:

"Faster level 2 charging in freezing temps"

I don't think this was explicitly called out in prior updates like it is now. I know this issue won't affect most people now that it's spring but it's a welcomed fix! Fingers cross it actually works!

 

[Rivian Roamer]

Upcoming software update 2015.10 looks to be fixing this issue! From the notes:

"Faster level 2 charging in freezing temps"

I don't think this was explicitly called out in prior updates like it is now. I know this issue won't affect most people now that it's spring but it's a welcomed fix! Fingers cross it actually works!

This was an output of the coordination of this sub, myself and Wassym. Thank you for everyone to sharing your data and anecdotes.

 

[Mellowyellow]

That is awesome albeit a bit late since things are really starting to warm up now.

 

[MarkNorman]

This was an output of the coordination of this sub, myself and Wassym. Thank you for everyone to sharing your data and anecdotes.

Thank you for this! What should we expect to see with this update?

 

[Glogic]

This was an output of the coordination of this sub, myself and Wassym. Thank you for everyone to sharing your data and anecdotes.

Thank you very much! It will be great to be able to have this work as expected.

 

[minnesnowta]

So, I finally got my R1T Tri Max and did some testing. It said out in 40F weather for 72 hours and got cold soaked. I upped the charge limit to 100 and watched it derate pretty aggressively. At 92% I took it for a very spirited drive for 9 miles. Watched it climb back to 92% at 11.2

This is almost exactly what I saw on my Gen 2 Dual Max this past weekend when I increased the charge limit to 100% while plugged into my 48A Tesla HPWC. Temperatures were somewhere around 40 degrees as well. Hopeful that the update rolling out fixes it!

 

[Rivian Roamer]

I just tested this on .10 and while my pack wasn't as cold as before (49F vs 46F) it held 11.1 kW up to 85%.

 

[Glogic]

I just tested this on .10 and while my pack wasn't as cold as before (49F vs 46F) it held 11.1 kW up to 85%.

How did it do after 85%? I just got the update but probably won't see another cold day anytime soon

 

[minnesnowta]

I know that this issue seems to have been resolved - but it was getting too warm here in MN to really test it when the relevant update was released. Now with manual preconditioning in 2025.18, we have a way to force the battery to warm up and resolve this issue manually if it does happen to occur again.

 

[millersntx]

I’ve had issues recently home charging as well. Starting at 11.2kw and dropping to 6.4 after a couple hours. Adapter getting hot. Going to try cleaning contacts with. Isopropyl alcohol today to see if that helps.

 

[millersntx]

Using a Tesla wall charger with an adapter

 

[HaveBlue]

Did my first L2 charge after upgrading software to 2025.06.30. As described below, it was a little disjointed with some confusing results, so can't draw any final conclusions. Some good, some bad.

The truck had been driven about 10 miles prior to starting the charge session at 14% SOC. ABRP battery temp 47.8F, Rivian battery temp 45F, motor temps 59/48 (front/rear). Ambient temp mid-30s. Charged for about 6 hours to 50% SOC with battery warming 0.5F/hr (48.2F), but motors warming more 66/60. Over the next hour, ABRP battery temp jumped to 55F, with motors to 68/62, and temp stayed there for another hour or so (61% SOC). When I next checked, ABRP battery temp had dropped back to 48.2F (68% SOC). Motors remained at 68/64. ABRP temp stayed at 48.2F with multiple syncs over the next 20 minutes. Since it was 1130PM and I was very confused, I stopped the charge at 70%. I checked the Rivian battery temp when charging stopped (50F), which was strange since it is usually 3-5F lower than the ABRP temp on my truck. A minute later, after stopping the charge, ABRP synced again, and was back to 55F. I have no idea what is going on with the ABRP temp readings.

I restarted the charge this AM, Rivian batter 41F, ABRP battery 46.4F, motors 39/35, SOC 70%. Charged steadily to 81% (2 hours) at Rivian 9.3kW. Battery only warmed to 47.5F, motors 46/44. At 81%SOC, experienced my standard throttle to Rivian 7.5kW. At 87%, experienced the my next standard throttle to Rivian 3.5kW (battery 48.2F, motors 51/50).

Initial indications are:
1 - THE BAD The new software does not help when trying to "top up" a cool battery. Warming rate hasn't appreciably changed.
2 - THE HOPEFUL There may be an indication of more aggressive warming with a deeper charge, but there may also be an issue with the validity of ABRP temperature data. Needs more testing.

One additional observation:
3 - THE CURIOUS My charger allows me to vary output in one amp increments. The initial throttle to 7.5kW matches 32A output. The 2nd throttle to 3.5kW matches 16A output. I find it interesting that the throttle steps match standard charger output options (every 8A).

The car can charge at any rate in 1A increments. The J1772 communication standard allows the following rates: 12, 16, 24, 32, 40, 48, 56, 64, 72, 80 (80% of the breaker) so the EVSE can only tell the car "here is the most I can supply." If the EVSE notices an issue, it can request the car to draw the next lower value. Note that these are the delivered amps and not the amount going to the car battery. The car may waste some in converting, cooling, heating or running systems.

Furthermore, KW is also made up of voltage and therefore the car is often not delivered 9.6kw on a 40A connection, for instance, due to voltage sag in not getting 240V.

 

[Dave Cundiff]

My understanding is that in the USA, single phase power is typically 120/240 volts, while three-phase power is typically 120/208 volts.

At different voltages, the relationship between amps and kW will be a different ratio.

Best to all!

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