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MASTER THREAD: 2021 Model 3 - Charge data, battery discussion etc

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I’ve started to see a few videos of 2021 MIC model 3 performance cars arriving in Australia.

As we eagerly await our 2021 MIC performance models in the U.K., I was wondering if anyone is Australia is on here who’s had a chance to dig into the batter pack details with either scan my Tesla or just experiments. How fast does it charge, what kind of range you’re getting? It would be great to know if the battery pack is any different from the Fremont cars, since the battery provider is LG in China for other models and some differences are noted.

This is just a geeky impatient question that I and maybe others might appreciate.
 
Yeah, Also the way I charge the car does not balance the BMS to the highest possible capacity in contrast to AAKEE, who does exactly that.

Yes, I guess thats the main explanation for my NFP Values.

I had NFP = 80.1kWh for six weeks.
Had 80.6 which topped 81kWh when I first connected SMT at about 1000km. After about one week I saw 80.1kWh and that was stable for six weeks. Then it started to climb about 0.1 each day or so until 81.4kWh.

This was about the same time as I reduced the daily charging scedule to 60% from first 80 to 70%. The 60% charge was lowered to about 55-56% before the NFP climbed really high.

If I had kept 80% I guess it would have stayed much lower.
 
I will go back and review your posts - I tend to forget things...
Went back and reviewed this post (which I had already extensively commented on and completely forgotten about 😆).

MASTER THREAD: 2021 Model 3 - Charge data, battery discussion etc

As has been discussed, the question is if the degradation threshold is still 77.8kWh. I asked about possible “pinning” behavior a couple posts later than this post (I doubt “pinning” behavior occurs - there is a definitely a display cap, but I think no pinning.) But anyway you can see on this vehicle you looked at the constant is inflated too; something like 140Wh/mi.

You would see pinning when charging, potentially - it might hit the display cap early and stay there as NFP increased by 1kWh over an hour or whatever. But upon discharge it would immediately click down the rated miles at the 0.955*140Wh/km rate. Because the energy content of the displayed rated miles has been expanded as much as necessary to fit the energy...which is why it looks like pinning occurs while charging.
 
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Very interesting thank you 😉 I didn't know sorry. So question stay about -R at the end. "New" release (?) but before "T" (?) On my side i will check pack reference of Q2 2021 LR.
Oh, nothing to apologize for, we’re all just trying to figure this stuff out. I don’t know much about the -R revision. I’ve only seen it mentioned a couple of times, and I think those users didn’t know their pack size. One was an early 2021 LR in the US that was getting this pack as a replacement, and the other was posted from a 2021 LR in Korea with VIN 913xxx, no other details.

I believe the standard 82kWh North American pack is revision -T like it is in Europe (just 1104422-00-T instead of 1104423-00-T), but I haven’t seen much evidence to confirm this. Tesla’s online parts catalog does list 1104422-00-T as a Model 3/Y battery, but I have to go to the Model Y parts list to see this. I find Tesla’s online parts catalog to be inconsistent when trying to find parts for specific models and variants.
 
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At least some of them do. It would be very nice to know what the degradation threshold/energy cap is from one of these new vehicles, from the energy screen. (@Stan930 ?). Preferably using interpolation method as well for accuracy...so three quick pics would be all we need...

If it is still around 78kWh, then they could potentially just use both battery types. It would not really matter (except for degradation characteristics and future unlocks).

We’ll find out. Hopefully they have switched everything over to the new cells at this point.
What exactly do you need? I have a 2021 lr w 82.1kwhh battery (per scan my tesla) (I read many of the posts with academic interest but didn't understand everything)
 
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What exactly do you need? I have a 2021 lr w 82.1kwhh battery (per scan my tesla) (I read many of the posts with academic interest but didn't understand everything)

In addition to an exactly concurrent screen capture from SMT, with the climate control off, in park, take these two pictures:

1st pic: Make sure you're in distance display mode, not % (energy) display. Display miles, and capture all three critical numbers. Also be sure it is in "average" mode.

2nd pic: Pick a NEARBY destination to navigate to, switch to this screen, and poke the magnifying glass in upper right to zoom in.

These pictures show my 2018 Model 3 Performance has about:

333Wh/mi*170mi / 0.809 = 70.0kWh of energy (nominal full pack); it had about 78kWh when new, and started showing miles lost at around 76kWh. (In other words, technically the max miles ever displayed were 310, but in current denomination, it had about 317. (77.8kWh/245Wh/rmi = 317rmi)

Yours will come up with an answer around 78kWh (I think - I'm not sure what the cap value/degradation threshold will be for a new 2021 LR 82kWh, which is what I'm trying to figure out). Even if your nominal full pack is 79.9kWh. (And that's ok and expected - SMT is correct, and the energy screen numbers are scaled down to the degradation threshold, I believe.)

(BTW, km are fine, and in fact preferred since they give 1.6x better precision - just too lazy to switch.)

IMG_9798.jpg
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In addition to an exactly concurrent screen capture from SMT, with the climate control off, in park, take these two pictures:

1st pic: Make sure you're in distance display mode, not % (energy) display. Display miles, and capture all three critical numbers. Also be sure it is in "average" mode.

2nd pic: Pick a NEARBY destination to navigate to, switch to this screen, and poke the magnifying glass in upper right to zoom in.

These pictures show my 2018 Model 3 Performance has about:

333Wh/mi*170mi / 0.809 = 70.0kWh of energy (nominal full pack); it had about 78kWh when new, and started showing miles lost at around 76kWh. (In other words, technically the max miles ever displayed
 

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Great! Thanks!!!!

So that shows that the degradation threshold is:

176Wh/mi*268mi / 0.607 = 77.7kWh (Obviously could be 77.8kWh, but really hard to know with that precision and it does not matter.)

So with the current software, you can lose 79.9kWh-77.7kWh = 2.2kWh of capacity before you will show any DISPLAYED loss of range. Obviously it will be obvious to you, because you have SMT. (If your nominal full pack when fully balanced is actually 81kWh, then you could lose 3.3kWh of capacity before showing any displayed loss of range.)

Tesla may of course at some point roll a software update to increase this degradation threshold (if all vehicles now have the 82.1kWh battery). That would come with a corresponding increase in displayed range, and the constant would fall back to 136Wh/rkm or 137Wh/rkm. (For you it is closer to 141Wh/rkm right now.). Depending on when that occurs and whether the threshold exceeds your NFP at that time, you may or may not see the maximum possible range.

But none of that matters - it's just bookkeeping. The main thing that matters is the energy, 79.9kWh for you. I was just curious how it worked on these new LRs. Looks like the degradation threshold is the same (77.8kWh) as it was for the older LRs. (It's been that value since 2020.)

Once you get below the threshold, the constant becomes a true constant, of course. This weirdness only happens with packs with NFPs exceeding the threshold (which is very common when new, of course).

Another way to think of it is that you currently have 79.9kWh/136.7Wh/rkm /1.6093rkm/rmi = 363 rmi of range when denominated in the "baseline" constant value. But of course right now you display 353 rated miles at full, because each mile contains more energy than that baseline right now.

In other words: 353mi@226Wh/mi is the same as 362mi@220Wh/mi.

Understanding this makes it easy to calculate capacity loss later (though of course it is trivial with SMT - you just take your max SMT kWh value ever seen as the denominator for your calculation, in a few years). As I described previously, without SMT, the only thing an owner can do is to measure their constant carefully using the trip meter (it's the only way I know of to determine your actual NFP without SMT, if your NFP exceeds the degradation threshold). And that method will only get you within about 0.5% or so probably, depending on the accuracy of your measurement.
 
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Great! Thanks!!!!

So that shows that the degradation threshold is:

176Wh/mi*268mi / 0.607 = 77.7kWh (Obviously could be 77.8kWh, but really hard to know with that precision and it does not matter.)

So with the current software, you can lose 79.9kWh-77.7kWh = 2.2kWh of capacity before you will show any DISPLAYED loss of range. Obviously it will be obvious to you, because you have SMT. (If your nominal full pack when fully balanced is actually 81kWh, then you could lose 3.3kWh of capacity before showing any displayed loss of range.)

Tesla may of course at some point roll a software update to increase this degradation threshold (if all vehicles now have the 82.1kWh battery). That would come with a corresponding increase in displayed range, and the constant would fall back to 136Wh/rkm or 137Wh/rkm. (For you it is closer to 141Wh/rkm right now.). Depending on when that occurs and whether the threshold exceeds your NFP at that time, you may or may not see the maximum possible range.

But none of that matters - it's just bookkeeping. The main thing that matters is the energy, 79.9kWh for you. I was just curious how it worked on these new LRs. Looks like the degradation threshold is the same (77.8kWh) as it was for the older LRs. (It's been that value since 2020.)

Once you get below the threshold, the constant becomes a true constant, of course. This weirdness only happens with packs with NFPs exceeding the threshold (which is very common when new, of course).
So from a warranty perspective I should hope for them to increase the degradation threshold? I still don't understand the rated range. 80kwh/250wh/mi= 320 mi. Or 82000wh/250wh/mi=328 mi
 
So from a warranty perspective I should hope for them to increase the degradation threshold? I still don't understand the rated range. 80kwh/250wh/mi= 320 mi. Or 82000wh/250wh/mi=328 mi

Yeah from a warranty perspective for you it definitely would be good if they increase the max range displayed and the degradation threshold. We'll see what they do. They may wait for 2021, who knows.... I don't like your chances if you hit 30% capacity loss at 56kWh and they say "no, you're at 255 rated miles which is 72% of 353 rated miles, so you don't qualify." (Realistically no vehicles without sudden battery failures have seen this type of loss though, so this is an academic point.)

I don't know where you are getting 250Wh/rmi from (that's the 2018/2019 AWD value of the line position - their constant was 245Wh/rmi). If you look at your energy screen carefully and drive to the line, you'll find the line is at around 225Wh/rmi. This means the charging constant is 220Wh/rmi (I don't know why it is 5Wh/mi less; it just always is).

79.9kWh/220Wh/rmi is 363 rmi as I said above. (This is your actual range denominated in the true baseline constant.)

But of course the threshold Tesla is using is 77.8kWh, so 77.8kWh/220Wh/rmi = 354rmi. (close enough - one of these numbers is off, since this is not 353 miles. Maybe the threshold really is 77.7kWh as calculated from your pictures. Small difference, doesn't matter of course.)
 
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Sorry. Fixated on the EPA rating of 250wh/mi.

The EPA rating is wall-to-wheels and reflects a conversion efficiency of 88.5% or so (it's given in the EPA docs explicitly; there's nothing hidden).

So 250Wh/mi (AC) *0.885 = 221Wh/mi (DC).

The EPA rating is also only 2 significant figures when viewed that way, so it's better to use 134MPGe:

134MPGe / (33.705kWh/Ge) = 3.98mi/kWh => 252Wh/mi (This is also a wall-to-wheels metric.)

So assuming 88.5% (that's not the right value - you'd have to look at the EPA document, but it's between 88.2% and 88.6% probably)...you get 223Wh/mi.

Anyway, all pretty close. Keep in mind that the test vehicle actually had more than 77.8kWh of energy - maybe 79kWh (also in the doc). So it all works out.
 
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So the efficiency number reported by the tripometer represents battery to wheels (and includes climate, sentry, computer etc?)

The trip meter represents battery-to-wheels. It includes all use when NOT IN PARK. When in Park, it records zero energy use no matter what. So definitely no Sentry, etc.

The other thing about the trip meter is that it appears to "miss" about 1% of energy use. Not a big deal but keep it in mind, and the amount missed does vary a bit depending on the use scenario.

And as described previously, because of the buffer, long-term, each rated mile that clicks off will correspond to 210Wh, not 220Wh (0.955*220Wh). (For your vehicle, with the current software. And because of your enlarged rated miles, it's closer to 216Wh for each of your displayed rated miles right now (0.955*226Wh).)
 
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The trip meter represents battery-to-wheels. It includes all use when NOT IN PARK. When in Park, it records zero energy use. So definitely no Sentry, etc.
In the evening when I leave work I turn on climate remotely (maybe 5 minutes prior to entering to cool the 100f+ cabin), and my initial e energy usage is extremely high (1000+wh/mi). Are you sure it's not accounted?
 
In the evening when I leave work I turn on climate remotely (maybe 5 minutes prior to entering to cool the 100f+ cabin), and my initial e energy usage is extremely high (1000+wh/mi). Are you sure it's not accounted?

Yes, quite sure (though it would be great if Tesla would change this at some point, or at least report that use as a separate field!). It's quite possible in your initial roll your energy use is also 1000Wh/mi, even after the pre-cool - 5 minutes will not be enough to bring down the temp and cool everything down from 150 degrees, probably. In AZ, your AC will still be cranking and might be using 1-2kW or more. (I do not know the maximum capacity of the AC system - maybe it can't exceed 1kW, not really sure - but it also doesn't matter, see below.)

Anyway, let's say you roll out of the parking lot really slowly for the first few hundred yards, at an average speed of 1mph. 1kW/1mph = 1000Wh/mi.

The first update to the trip meter can happen after just a few yards (it depends), so if you've traveled that distance slowly, the value can be very high and suffer from problems with a denominator that is very small. (Near divide by 0. I don't know what sort of resolution they use for their internal calculations, for the denominator.) Also if you spend any time in drive not moving that will REALLY add up especially for that first update.

Finally, you have to get the car moving, which takes a tremendous amount of energy and will always bring up your Wh/mi. (30mph takes about 50Wh for a 4000 pound car, so if you get to 30mph in a tenth of a mile that would be 500Wh/mi. (1/2*4000lb*(30mph)^2/0.95 = 48Wh) So it all adds up.

I think you'll find that if you quickly get moving to 20mph and then look at the usage after 1 mile, you'll find it's a very reasonable result.

But you can experiment with it. Easy to determine. (Just don't do the pre-cool, but use AC when you get in the car, and see what you get. Might want to open those windows though, haha.)

Anyway, veering wildly off topic here - trying to get back to specific discussion about 2021. Thanks again for your data - all my curiosities have been resolved for now!
 
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Yes exactly this is what I mean:
-Only once the BMS calculates a Nominal Full Pack below 77,1kWh you saw a drop below 499km.
-Only once the BMS calculates a Nominal Full Pack below 80,6kWh you see a drop below 508/509km.

Just following up and summarizing now that we have the data (all data below is within about 0.2kWh, don't assign much significance to 77.8kWh precisely - it might well be 77.7kWh):

2018-2019: Drop below ~76kWh, see drop below 499km. (Least evidence-backed piece of data, but if behavior is consistent with subsequent years this is correct.)
2020: Drop below 77.8kWh, see drop below ~518km. (LR 18")
2021: Drop below 77.8kWh, see drop below 568km. (LR Non-P, LR Non-P 82kWh)
2021: Drop below 80.6kWh, see drop below 508/509km. (Performance)

This is only at the current time and the 2021 information may change if software gets updated. And critical observation here is that this dealing with values in excess of the threshold is done without "pinning." It's done with a "variable constant." (Quite a contradiction!)


Is this variable rated consumption figure confirmed by data yet? Otherwise I would assume that every Nominal Full Pack below around 79kWh shows a reduction in Rated Range.

Looks like the evidence provided so far strongly suggests the threshold (for now) is 77.8kWh/77.7kWh for the LR Non-P 82kWh. Regarding the behavior of the variable consumption figure until the threshold is reached - I can't see another way for it to be implemented right now, but observations over time or over vehicles would be needed. Datapoints from more LR 82kWh vehicles - especially ones that have 81+kWh of energy, and closer to 78kWh of energy, energy screen info, screen captures in car, and concurrent SMT info would be nice (just as above). We should just see a nice smattering of data showing that rated miles and SMT align if you assume a variable constant (haha) equal to about 136.7Wh/km * Nominal Full Pack / 77.7kWh, for energies above the stated threshold. That would be confirmatory. I guess rather than a variable constant we should call it a "piecewise-defined value which is a constant for NFP energies below the threshold." Haha. (And crucially when looking at the energy screen, it always IS a constant.)

But I've pretty much seen enough at this point. As I said, I can't see another way for it to be implemented and we actually have a lot of data now.
 
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