Preconditioning confusion

[Throwdown]

Actually, before the update during cold weather I ALWAYS manually turned on my seat heater and steering wheel heater about 15 mins before I left for work while plugged in, even when the climate control reported 50F-60F and it ALWAYS has heated the battery up to 70F-80F.

Same now for using the schedule to pre-heat it in the am and now in the pm before I leave work where as previously when the outside temp was < 40F at work, the

100% confirmed...had a schedule setup for 7am. It's been below 0F for several days now and my garage is uninsulated. Battery would've been probably in the 20-25F realm and I didn't drive for a few days, so it was cold-soaked. When I got in this morning with the scheduled preconditioning the battery was at 51F and no snowflake on the dash. Exactly what Rivian said to expect.

Before this feature existed my battery wouldn't be anywhere near 50F on departure, even if I manually set my charging schedule to try and complete a charge right before I left. Reason...I only do about 30 miles per day and only charge at 24A. There literally no way charging alone would warm my battery enough.

That's different than mine, mine would always being the range of 50F before this update when I left after charging. I've never seen my battery lower than 40F when sitting in the garage not charging. I charge at max amperage because I only have a short window to charge

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[Throwdown]

@Throwdown have you openEd a ticket with Rivian? I don’t know if it should or shouldn’t warm the battery if it’s already 50 degrees, but if you feel there’s something wrong with your vehicle maybe it would be the thing to do. I’m pretty sure beating this dead horse isn’t going to fix it.

You are correct I will, it's time to un-hijack OPs thread.

 

[Riviot]

Well, shit... Here I am trying to prove @Throwdown wrong, and I just confirmed it.

Started last night at 70%/226 miles and 39°F. Set preconditon for cabin at 77°F @ 0800. Cold battery, cold motors:

Came out of my nice cozy warm bed to snap these photos. I saw 71%/230 miles at about 0705:

It used 1.7kWh to warm cabin up to 61°F, negligible motor and battery temp change, but they did go up!

I don't think I'll be driving today, so I'll test again in the AM. This time I'll do MAX heat, only floor vents on.

 

[Throwdown]

Well, shit... Here I am trying to prove @Throwdown wrong, and I just confirmed it.

Started last night at 70%/226 miles and 39°F. Set preconditon for cabin at 77°F @ 0800. Cold battery, cold motors:

Came out of my nice cozy warm bed to snap these photos. I saw 71%/230 miles at about 0705:

It used 1.7kWh to warm cabin up to 61°F, negligible motor and battery temp change, but they did go up!

I don't think I'll be driving today, so I'll test again in the AM. This time I'll do MAX heat, only floor vents on.

Basically my point this entire time other than the banter back and forth on what optimum battery temp for preconditioning before departure (not DCFC) should be. I just don't think it's doing more than it ever did and if they give the option to heat the battery for departure and pull from the grid to not impact the vehicles efficiency, then it should make the battery much much warmer than it is. I know a thing or two about batteries and thermal management.

 

[Riviot]

Basically my point this entire time other than the banter back and forth on what optimum battery temp for preconditioning before departure (not DCFC) should be. I just don't think it's doing more than it ever did and if they give the option to heat the battery for departure and pull from the grid to not impact the vehicles efficiency, then it should make the battery much much warmer than it is. I know a thing or two about batteries and thermal management.

How do other companies warm cold batteries from standstill? What is Rivian missing that could heat them?

 

[madugula]

Scheduled Charging will maintain the temperature of battery and cabin. During driving it does not maintain the battery temperature only Cabin?

 

[SeaGeo]

Basically my point this entire time other than the banter back and forth on what optimum battery temp for preconditioning before departure (not DCFC) should be. I just don't think it's doing more than it ever did and if they give the option to heat the battery for departure and pull from the grid to not impact the vehicles efficiency, then it should make the battery much much warmer than it is. I know a thing or two about batteries and thermal management.

It does. I've definitely left with a cold battery with my truck being plugged in over night before. The preconditioning feature that's enabled now will use the motors (as needed) to get it up to a temp that they think it needs to be (which appears to be in the mid 40s to 50s). Whether that's the *optimal* temperature is probably a slightly different conversation.

 

[R.I.P.]

Well, shit... Here I am trying to prove @Throwdown wrong, and I just confirmed it.

Started last night at 70%/226 miles and 39°F. Set preconditon for cabin at 77°F @ 0800. Cold battery, cold motors:

Came out of my nice cozy warm bed to snap these photos. I saw 71%/230 miles at about 0705:

It used 1.7kWh to warm cabin up to 61°F, negligible motor and battery temp change, but they did go up!

I don't think I'll be driving today, so I'll test again in the AM. This time I'll do MAX heat, only floor vents on.

What you are seeing here is 100% expected behavior. If the pack is between 40 and 50°, it will not normally waste energy to try to get it warmer unless the vehicle is headed for DCFC.

Yes, there are people that feel the battery should be warmer, but most of us in the business, to include Rivian, disagree.

 

[Throwdown]

How do other companies warm cold batteries from standstill? What is Rivian missing that could heat them?

Well the rivian can it's just inefficient, they use the motors. Other cars have an electronic heater that warms the coolant and send it through the battery and or a heat pump that heats the coolant and sends it through the battery. A taycan for example uses a HV heater and a heat pump

 

[Riviot]

What you are seeing here is 100% expected behavior. If the pack is between 40 and 50°, it will not normally waste energy to try to get it warmer unless the vehicle is headed for DCFC.

Yes, there are people that feel the battery should be warmer, but most of us in the business, to include Rivian, disagree.

Ah I see, so I need to get the truck colder than 40°F. Check! I'll move it outside after breakfast and run the test again tomorrow if it gets below 40°F.

 

[Throwdown]

Ah I see, so I need to get the truck colder than 40°F. Check! I'll move it outside after breakfast and run the test again tomorrow if it gets below 40°F.

No doubt, it's always looking at the battery temp and doing the minimum to keep it in its safe operating range, my gripe came with the latest update for departure battery condtioning. some people are seeing what I would expect in terms of departure battery temp, others are not.

 

[Supratachophobia]

I just wish there was one of two options. Do it like Tesla and assume if you are on shore power, any HVAC activation draws from the wall AND heats the battery up.

Or, have a button labeled "FIIDCWICWUEFUPRBD". Obviously that means F#$* It, I Don't, Care, What It Costs, Warm Up Everything From Utility Power, Rateplan Be Damned

 

[zefram47]

How do other companies warm cold batteries from standstill? What is Rivian missing that could heat them?

My MINI didn't even have a means of warming the battery. It just pulled power below 32F and naturally warmed itself through driving. It sucked. You can debate whether or not 50F is sufficient, but it's a hell of a lot better than a pack that's below freezing and you dramatically reduce performance. In my MINI I'd get only about 50% acceleration in the single-digits and it would take close to 30 min before I'd get back up towards 80%. On the Rivian that wouldn't matter much, but only having 90 hp in a 3100 lbs car was a little rough sometimes.

 

[Opiate]

I think it only preconditions the battery if it’s plugged into your charger and that whole time of use on or off. The riv charging is better when battery is cooler (not hot) . It has a thermal reduction when it gets warm.

 

[antennariidae]

Thanks everyone for the responses. I am still unclear whether it will pull shore power when the process is started manually, or only if it is scheduled. It really shouldn't have to be this confusing!

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