Countering cold, winter weather effects for those living in the northern states.

[Nixapatfan]

Such a minor thing to worry about. I've never seen my already cold soaked battery get colder during the drive only see the temp rise. I'm sure part of it is the outside temperature is usually trending upwards from overnight lows so if anything it might be gaining conducive heat from outside air.

The battery is such a huge thermal mass it takes a very long time to lose heat, to lose 20f would take many hours.

Added insulation is double edged sword, will cause problem in summer or when DC fast charging safer to have a cold battery than one that can't shed heat.

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[Billyk24]

Such a minor thing to worry about. I've never seen my already cold soaked battery get colder during the drive only see the temp rise. I'm sure part of it is the outside temperature is usually trending upwards from overnight lows so if anything it might be gaining conducive heat from outside air.

The battery is such a huge thermal mass it takes a very long time to lose heat, to lose 20f would take many hours.

Added insulation is double edged sword, will cause problem in summer or when DC fast charging safer to have a cold battery than one that can't shed heat.

Your R1 may not lose heat "fast" but I am seeing it in real time via Car Scanner Pro app on my EV which is not a Rivian. Battery details and thermal regulation in cold winter weather is important to me.

 

[usulio]

Problem solved. Drop the R2 reservation and go to another brand.

Not sure what your beef is here. You are complaining about your Mach-E. People are reporting neutral to good experiences with their R1. Then you are extrapolating to complain about R2, a vehicle that nobody owns yet.

Meanwhile, what other brand are you going to go with?

So far, the only ones who have tested R2 in cold weather is Rivian.

 

[Mos Eisley]

That is not the problem/question. The question is once you leave the garage and enter the cold winter weather of 10f, what will the R2 battery pack temperature do? How well is it insulated/protected from bitter winter weather? If not very well, then those of us living in the cold northern states may need to rethink about going forward with a R2.

Humbly suggest, you're overthinking it. And a heat pump is a solution as it's been demonstrated that lack of a heat pump has, by far, the most negative impact on range and performance in extreme cold. With current, tech, adding any amount of significantly more distance between outside temps and the battery would effectively put them in the cabin.

 

[Mos Eisley]

Cold Weather Testing by Rivian - Rivian Stories | Electric Vehicle Adventures

"In extremely cold conditions we use some battery energy to keep the cells in our battery above 14°F to provide controlled vehicle performance. Some EVs have electrical heaters to heat the battery up, which is another component — more cost, more mass and a drain on electrical supply. Instead, we’re using our inverter and motor to generate heat — even while stationary our traction system can generate substantial heat for the battery. And we use that heat to warm the battery to the point where it can deliver full performance. Our battery is uniquely designed to operate in super cold conditions, all the way down to an ambient temp of -40°F."

 

[mkhuffman]

Your R1 may not lose heat "fast" but I am seeing it in real time via Car Scanner Pro app on my EV which is not a Rivian. Battery details and thermal regulation in cold winter weather is important to me.

Rivian displays the battery temperature in the vehicle, so you can monitor it without using a OBDII scanner. (OBDII scanners don't work in a Rivian anyway.)

In addition to the heat pump, Rivian uses the heat from the motors to heat the battery. When it does this, it impacts efficiency. Of course. I do not think the MME uses motor heat to assist battery warming.

The point is the MME and the R1 have different battery conditioning systems. The R1 seems to do a better job than the MME at keeping the battery warm.

It is possible if you drive in All Purpose, with all the motors engaged, you generate more heat for the battery. I have noticed that the rear motors get much colder in Conserve than when traveling in All Purpose. Using all the motors reduces efficiency.

What is your concern? Range? Efficiency? Just battery temp?

My guess is the R2 will be as good or better at this than the R1, since Rivian has learned a lot from the R1, and those lessons learned are part of the design of the R2.

 

[Budman]

I live in MN and if you have -20 and 25 - 30 mile an hour wind you may see 50% range loss. Other times around 0 and sunny with no wind and starting warm it is more like 20% or so. There is a graph that has been posted numerous times in this forum of someone who makes a regular 160 mile trip in all different weather so you can see the effect of temperature.

Here is that graph again.

I"ve been through 3 winters with my R1T, first a Gen 1 for 55,000 miles and now a Gen 2 with 32,000 miles. I live in MN and have a cabin in northern WI we visit frequently (that's how I get so much data for this graph).where temperatures routinely drop into the -20 deg F range overnight.

I charge on a 40 amp L2 charger in a garage. I rarely set a charging schedule and never preheat the battery before departure and rarely preheat the cabin before departure. Being in the garage and having been "recently" 'charged (like within the last 8 hours) the battery is typically between 30 and 50 degrees. While driving it's in the low 30's.

I have a max pack with NMC and really don't worry about winter range. I just know it's going to be 30% less at 0F compared to 70F. I get plenty of cabin heat from the Gen 2 heat pump even at -20F. I just drive the R1T and plan appropriately for the weather.

I personally would never get a small battery pack with LFP chemistry in a cold climate. I know LFP is the big talking point right now because it does have a few good features but the calibration issues and cold weather charging issues makes it unacceptable for my use case.

 

[mkhuffman]

Here is that graph again.

I"ve been through 3 winters with my R1T, first a Gen 1 for 55,000 miles and now a Gen 2 with 32,000 miles. I live in MN and have a cabin in northern WI we visit frequently (that's how I get so much data for this graph).where temperatures routinely drop into the -20 deg F range overnight.

I charge on a 40 amp L2 charger in a garage. I rarely set a charging schedule and never preheat the battery before departure and rarely preheat the cabin before departure. Being in the garage and having been "recently" 'charged (like within the last 8 hours) the battery is typically between 30 and 50 degrees. While driving it's in the low 30's.

I have a max pack with NMC and really don't worry about winter range. I just know it's going to be 30% less at 0F compared to 70F. I get plenty of cabin heat from the Gen 2 heat pump even at -20F. I just drive the R1T and plan appropriately for the weather.

I personally would never get small battery back with LFP chemistry in a cold climate. I know LFP is the big talking point right now because it does have a few good features but the calibration issues and cold weather charging issues makes it unacceptable for my use case.

Thank you so much for taking the time and effort to track and record the data. I know you have shared this multiple times before, but I don't think I have ever thanked you personally.

Your data is a great resource and really the "worst case" of what you can expect in cold weather, because you don't do anything special - just park and drive.

The cool thing about this data is that if you do extra things, like park in a warmer garage so you start with a warmer battery, or precondition, then you can do better.

Love it and thanks again!

 

[Golfer04]

I got a new tri max September 30. Oct-Dec my efficiency was 2.65 combined in all types of driving over 7500 miles. I now have 11,500 on it and efficiency average is 2.26. I take all the steps to warm & keep battery warm, but it is a myth that you don't lose range in cold weather if you follow "X" routine.

 

[Budman]

Thank you so much for taking the time and effort to track and record the data. I know you have shared this multiple times before, but I don't think I have ever thanked you personally.

Your data is a great resource and really the "worst case" of what you can expect in cold weather, because you don't do anything special - just park and drive.

The cool thing about this data is that if you do extra things, like park in a warmer garage so you start with a warmer battery, or precondition, then you can do better.

Love it and thanks again!

Thank you. Means a lot to me because way back before I got my R1T I had a deposit on a Mustang Mach-e and was watching the mach e forums. There was a 12V battery issue then and I remember you making very intelligent and helpful posts on that issue. So the respect is mutual.

 

[Cycliste]

On a serious note, EVs lose range in the cold because of the temperature effect on battery chemistry. It is what it is.

I often think the gauge showing range in EVs is too good. In an ICE vehicle, you look at the gauge and only think in quarters of a tank and not some minute by minute estimation of range down to the mile/kilometer. Humans don’t seem to do as well with this. Maybe we should have a setting for range that displays an analog gauge like in an ICE vehicle.

 

[Dark-Fx]

That is not the problem/question. The question is once you leave the garage and enter the cold winter weather of 10f, what will the R2 battery pack temperature do? How well is it insulated/protected from bitter winter weather? If not very well, then those of us living in the cold northern states may need to rethink about going forward with a R2.

Top of the battery in R2 is the actual cabin floor. Should do better than R1 for winter weather, but they haven't really given us enough detail to answer your question in a complete enough manner.

This just feels like a post that's trying to scare people off R2 than looking for a real answer.

 

[mkhuffman]

... but it is a myth that you don't lose range in cold weather if you follow "X" routine.

Who says it is a myth?

It is a fact that cold weather significantly impacts range.

 

[VandalSibs]

On a serious note, EVs lose range in the cold because of the temperature effect on battery chemistry. It is what it is.

I often think the gauge showing range in EVs is too good. In an ICE vehicle, you look at the gauge and only think in quarters of a tank and not some minute by minute estimation of range down to the mile/kilometer. Humans don’t seem to do as well with this. Maybe we should have a setting for range that displays an analog gauge like in an ICE vehicle.

I just set my driver's display to only show % remaining on the battery. Which is what an old-school fuel level gauge is, essentially.

 

[VSG]

I just set my driver's display to only show % remaining on the battery. Which is what an old-school fuel level gauge is, essentially.

I really think % should be the default, instead of "miles", because most people seem to misinterpret what the "miles" number means.

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