Battery temp of 15°F now appears to be where Rivian stops aggressively heating the battery

[1stPlace]

I think the battery temp can make somewhat of a difference in range. In cold weather, I get 1.3 mi/Kw if battery is 35F, but get 1.8 to 1.9 mi/kW if the battery is warmer (45F +)

Battery temp does make a difference but if you look at the whole of energy expenditure, heating the battery with energy from the battery upfront does not improve total trip efficiency.

So again, to reiterate, OP won't be able to condition to a 50degF battery at this time unless it is plugged in. Maybe a level 1 extension cord like suggested earlier will suffice. The solution will come when manual pre-condition for DC charging is added to the software. Hopefully there is a button in the phone app so you don't have to go to the car and leave the key.

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[André]

No choice for this now unfortunately but, it should be coming s00n...

What updates and features can owners expect soon?

• Google Cast Integration: Available in the next update (2024.47), it will support over 3,000 apps, including YouTube.
• Text-to-Speech Messaging: A new voice stack will bring this feature by 2025, ensuring a refined user experience.
• Energy App 2.0: A comprehensive update will offer detailed insights into energy usage, charging patterns, and sustainability tips.
• Manual DC Fast Charge Preconditioning: This highly requested feature will arrive in early 2025.
• Tire Size Configuration: Available in Q1 2025, this update lets users adjust tire settings directly.
• Launch Mode: Returning in 2025 with exciting new features for Gen 1 Quad owners.

https://riviantrackr.com/news/rivians-software-and-tech-roadmap-highlights-from-todays-qa/

Manual DC fast charge preconditioning is not the right answer to this issue as it will warm-up the pack to 85F. Cabin preconditioning should use the charger if plugged in to warm the pack to 50F for normal driving with full range available for that purpose.

 

[Rade]

Good information! Thank you for sharing!

 

[DetroitRed]

This is why I wish they would do the math and have a charging routine that would trigger charging prior to departure whatever the math says.

If the math says it needs 5 hours to hit target charge level...start 6 hours prior to time of departure.

Free heating like you said!

This would be a nice feature. Unfortunately right now, the system is also bad at estimating the charge time with a cold battery. Last night with my battery at ~30°F, I plugged in and got a 12-hour estimate. In reality, once the battery warmed up from charging, the rate increased, and charging was finished in 6 hours.

 

[Greg Chick]

This would be a nice feature. Unfortunately right now, the system is also bad at estimating the charge time with a cold battery. Last night with my battery at ~30°F, I plugged in and got a 12-hour estimate. In reality, once the battery warmed up from charging, the rate increased, and charging was finished in 6 hours.

My experience too. The temps. seem to be the enemy of EV charging. This is a big task for Rivan, but the same task for all EV makers. The maker that solves it first, wins! Physics is the base of the issue and economoics is the top of the issue.
I once used up 14 miles of range driving up a one thousand ft. elevation grade that was 1 mile road distance. It was below freezing! Incidently, I got home with zero % battery range in the blizard and it was driving home after buying my first EV, my R1T . Welcome to EV world!

 

[KootenayEV]

I have been noticing this difference as compared to last winter, but haven't had cold enough temps here yet to see the new threshold. I generally prefer it day to day, as I generally prefer to reduce total energy through the system and I have a steady-state highway commute for the most part that doesn't require much in the way of regen. So I plug in when I get home; battery is warm enough so doesn't need to precondition, and charging maintains battery heat passively. By morning it has cooled off somewhat, but not enough to trigger preconditioning using the motors (unlike last year, where it did this majority of the time). Commute maintains temp until I get home and plug in again (generally 4 nights a week I plug in).

I am however really looking forward to the manual precondition button - hopefully it is in both the app and the vehicle. I have a few use cases for this:
- many fast charger networks in Canada are still missing from the navigation, so I can't rely on the nav system to trigger pre-conditioning (e.g. Chevron On the Run units)
- I go backcountry skiing regularly at two locations that are 3,500 ft above my house by road, and on the way back home (particularly from Whitewater area), I have to ride the brakes. Being able to schedule pre-conditioning would be incredibly helpful here to save my brakes! (Despite my earlier comment on reducing energy through the system, I'd rather pay for a few kWh than to redo my brakes sooner... and I'm leaving at least a few kWh of regen on the table by using the manual brakes)
- When towing in my immediate region in shoulder season, I can't use the navigate to DCFC trick as they are all too far from me to trigger pre-conditioning, and as mentioned above, it is very mountainous in all directions from my house!

 

[Rividiculous]

This thread is a reason I love this forum. I have been wondering lately why my battery seems to stay pretty cold on cold days. (I imagined it would warm up even when it's already 30 F.)

Question: Would it make sense to give the battery extra heat (say, warm it up to near the max safe temperature) before departing for a long drive on a sub-zero day (assuming you are plugged in to a charger before departure)?

If so, it would be cool if one could tell the Rivian approximately how far you expected to drive and then the car calculated the optimal battery temperature at which to start the trip for maximum range during the trip (based on your input and the weather conditions and forecast).

If you are driving two miles to the grocery store and will then be plugging back in, you probably want the battery heated just enough to perform well there and back (including during a cold soak) but you don't care about range.

If you are about to drive 200 miles in frigid temperatures, you probably want the battery heated up pretty high with grid energy so it stays warm longer from the heat.

If it's cold, your Rivian app could ask you approx how far you were going when you set the climate to pre-heat or something like that.

Is that a good idea? (It might not be! I'm NOT an engineer and know little about EV batteries.) Does Tesla do something like it? Should Rivian?

 

[KootenayEV]

This thread is a reason I love this forum. I have been wondering lately why my battery seems to stay pretty cold on cold days. (I imagined it would warm up even when it's already 30 F.)

Question: Would it make sense to give the battery extra heat (say, warm it up to near the max safe temperature) before departing for a long drive on a sub-zero day (assuming you are plugged in to a charger before departure)?

If so, it would be cool if one could tell the Rivian approximately how far you expected to drive and then the car calculated the optimal battery temperature at which to start the trip for maximum range during the trip (based on your input and the weather conditions and forecast).

If you are driving two miles to the grocery store and will then be plugging back in, you probably want the battery heated just enough to perform well there and back (including during a cold soak) but you don't care about range.

If you are about to drive 200 miles in frigid temperatures, you probably want the battery heated up pretty high with grid energy so it stays warm longer from the heat.

If it's cold, your Rivian app could ask you approx how far you were going when you set the climate to pre-heat or something like that.

Is that a good idea? (It might not be! I'm NOT an engineer and know little about EV batteries.) Does Tesla do something like it? Should Rivian?

Interesting idea! When I go on winter road trips, I do want my battery as warm as possible, so I time my charging to finish only an hour or two before my planned departure time in the morning (as opposed to my usual habit which is to charge right after driving home from work to keep the total energy expenditure lower by minimizing pre-heating).

 

[Greg Chick]

Interesting idea! When I go on winter road trips, I do want my battery as warm as possible, so I time my charging to finish only an hour or two before my planned departure time in the morning (as opposed to my usual habit which is to charge right after driving home from work to keep the total energy expenditure lower by minimizing pre-heating).

Same here.

 

[edman007]

This is why I wish they would do the math and have a charging routine that would trigger charging prior to departure whatever the math says.

If the math says it needs 5 hours to hit target charge level...start 6 hours prior to time of departure.

Free heating like you said!

I do it with my EVSE using a couple scripts. It seems like if the pack is actually cold, like 25F, even on L2, it will slow charge and heat the pack before full speed charging. I find when I do this, the pack is 50-55F when I leave in the morning, regardless of outside temps.

It will warm-up the pack only if the preconditioning of the cabin brings your range below the range set and consequently start to charge. Tesla does precondition the pack automatically and Rivian should too.

I think a lot of people are mistaking cold pack temps for the reason their vehicle is inefficient. It's not, and that has nothing to do with why they heat the pack. When cold, you lose charge and discharge speeds, that impacts charging, and general vehicle performance, it needs to be heated to maintain a safe performance level.

Outside of those performance numbers, range is mostly impacted by stuff like air density, low tire pressure, and cabin temps/heating requirements. Spending 3kWh to warm up the pack, even for a long road trip, will generally reduce your range, doing it on a short trip is extra bad because you see a big draw of power, and your trip is still mostly with a cold pack.

I think that's why Rivian changed the set point, the cold pack improves efficency, despite what everyone else seems to think they know about EV efficency

 

[André]

I do it with my EVSE using a couple scripts. It seems like if the pack is actually cold, like 25F, even on L2, it will slow charge and heat the pack before full speed charging. I find when I do this, the pack is 50-55F when I leave in the morning, regardless of outside temps.



I think a lot of people are mistaking cold pack temps for the reason their vehicle is inefficient. It's not, and that has nothing to do with why they heat the pack. When cold, you lose charge and discharge speeds, that impacts charging, and general vehicle performance, it needs to be heated to maintain a safe performance level.

Outside of those performance numbers, range is mostly impacted by stuff like air density, low tire pressure, and cabin temps/heating requirements. Spending 3kWh to warm up the pack, even for a long road trip, will generally reduce your range, doing it on a short trip is extra bad because you see a big draw of power, and your trip is still mostly with a cold pack.

I think that's why Rivian changed the set point, the cold pack improves efficency, despite what everyone else seems to think they know about EV efficency

Doesn’t matter to me if I lose 10-15% of range in the first 10 miles because of inefficiency due to cold pack or because of energy being used to warm-up the pack. If I could leave home with a pack at 50F I wouldn’t lose that range for no good reason. It‘s a simple fix to heat the pack using power of the charger while heating the cabin before leaving without having to force charging by increasing the range set, as Tesla does BTW.

 

[edman007]

due to cold pack or because of energy being used to warm-up the pack.

That's the point, it now doesn't turn on the heaters until it's below 15F, as long as you are above that. So it doesn't use energy to "warm-up the pack", it leaves it cold.

That said, if you charge shortly before leaving, charging does heat the pack, so it will be well above 15F. Using wall power to heat the pack would be energy you pay for to heat it, even if you don't see it impacting the % of the battery.

 

[Greg Chick]

I think the big issue with charging cold is when DCFC. I think many here are suggesting the home cheaper charging and L2 charging. L2 charging is less damaging on batteries? and DCFC is more so especially when below freezing?
Then the separate issue of range decrease because of a cold battery and if any range is used to warm up cold batteries. And to what gain is warming a battery if this or that...

 

[André]

That's the point, it now doesn't turn on the heaters until it's below 15F, as long as you are above that. So it doesn't use energy to "warm-up the pack", it leaves it cold.

That said, if you charge shortly before leaving, charging does heat the pack, so it will be well above 15F. Using wall power to heat the pack would be energy you pay for to heat it, even if you don't see it impacting the % of the battery.

No true at least in my 2024 Quad R1T. It does warm the pack to 30F while driving and that is why range usage is abnormally high in the first few miles. Same trip, same conditions and range usage is much better after the first 10 miles when the pack is warmed-up. It doesn’t warm the pack above 15F when plugged in… which is nonsense when you want to use 100% of the range on longer trips.

 

[TTedP]

That's the point, it now doesn't turn on the heaters until it's below 15F, as long as you are above that. So it doesn't use energy to "warm-up the pack", it leaves it cold.

That said, if you charge shortly before leaving, charging does heat the pack, so it will be well above 15F. Using wall power to heat the pack would be energy you pay for to heat it, even if you don't see it impacting the % of the battery.

best explanation, thanks.

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