OK 4680 LR owners, anyone above 10k-15k miles yet?

[h0mersimps0n]

So I am original owner of a 2018 M3P with 63k miles on it and a 2022 MYP (2170 pack) with 12,500 miles on it.

Both vehicles dropped range by almost 8% at about the 10-15k mark, despite the foolishness/circus act procedures trying to get the BMS to recalculate.

I have always charged to 90%, less than a dozen times on each vehicle gone to 100% for trips. Supercharge rarely. Almost never below 10%.

90% charge for my M3P has held pretty steady at 246
90% charge for my MYP is now a disappointing 251

SO, I was wondering if the 4680 MYLR deliveries out of Texas are seeing the same 8-10% loss by 15k miles?

 

[MP3Mike]

SO, I was wondering if the 4680 MYLR deliveries out of Texas are seeing the same 8-10% loss by 15k miles?

There have been no 4680 MY LR deliveries.

 

[240vPlug]

I would question if you actually lost 8%. Using the predicted range to calculate degradation is not at all accurate. The mileage shown is really only useful while on a road trip and any other time I just show the SOC instead.

IMO the most accurate way to calculate is by the usable capacity of the battery. What was the usable capacity in kWh when new and what is the usable capacity now? That will tell you how much degradation you have. I suspect it will be much less than 8%.

As for the 4680 I don’t know that anyone has one with 15k on it as deliveries to customers didn’t start until sometime in June.

 

[fiehlsport]

I don't think anyone with a 4680 car has had it for much more than a month at this point. Nobody even has 10,000mi.

Your degradation sounds totally normal on the M3P and MYP though. At 100% 280mi is about right. You can charge to 100% and supercharge a lot more and it's not going to harm the battery at all, it's not that sensitive.

 

[Fourdoor]

So I am original owner of a 2018 M3P with 63k miles on it and a 2022 MYP (2170 pack) with 12,500 miles on it.

Both vehicles dropped range by almost 8% at about the 10-15k mark, despite the foolishness/circus act procedures trying to get the BMS to recalculate.

I have always charged to 90%, less than a dozen times on each vehicle gone to 100% for trips. Supercharge rarely. Almost never below 10%.

90% charge for my M3P has held pretty steady at 246
90% charge for my MYP is now a disappointing 251

SO, I was wondering if the 4680 MYLR deliveries out of Texas are seeing the same 8-10% loss by 15k miles?

If you always charge to 90% then you have not done the "foolishness/circus act" to get the BMS to recalculate. Several months ago I got lazy and started charging to 80% every day rather than varying the charging regimen on my car. After a couple months of charging to the same 80% and doing the same commute back and forth to work while seeing no change in predicted range my BMS took a dump and estimated range did a very rapid change over less than a week and less than 1000 miles from 286 miles of range at 19,154 miles on the odometer to 268 miles of range at 20,000 miles on the odo. After that I went back to my routine of charging to a different level each day, and over the first MONTH AND A HALF of this there was no significant change, then the range started a fairly linear rapid rise back up to 284 miles of range at 27,880 miles on the odometer. This linear increase in reported range took A MONTH AND A HALF. So, resetting the BMS on my car took THREE MONTHS... it is not something that you do over night. Tesla 3 and Y are the only EV's I know of with this BMS battery capacity measurement problem. Anyway, you don't have 8% battery degradation, you have bad charging habits if you want accurate BMS results. My car has 6% degradation at almost 28,000 miles, not the 12% degradation at 20,000 miles that was indicated when I let my charging habits get lazy. I find the idea of being down 8% on range after only 12,500 miles to be unlikely, but I am not surprised this amount of degradation is falsely being displayed due to your charging habits.

Keith

 

[Jkasm]

If you always charge to 90% then you have not done the "foolishness/circus act" to get the BMS to recalculate. Several months ago I got lazy and started charging to 80% every day rather than varying the charging regimen on my car. After a couple months of charging to the same 80% and doing the same commute back and forth to work while seeing no change in predicted range my BMS took a dump and estimated range did a very rapid change over less than a week and less than 1000 miles from 286 miles of range at 19,154 miles on the odometer to 268 miles of range at 20,000 miles on the odo. After that I went back to my routine of charging to a different level each day, and over the first MONTH AND A HALF of this there was no significant change, then the range started a fairly linear rapid rise back up to 284 miles of range at 27,880 miles on the odometer. This linear increase in reported range took A MONTH AND A HALF. So, resetting the BMS on my car took THREE MONTHS... it is not something that you do over night. Tesla 3 and Y are the only EV's I know of with this BMS battery capacity measurement problem. Anyway, you don't have 8% battery degradation, you have bad charging habits if you want accurate BMS results. My car has 6% degradation at almost 28,000 miles, not the 12% degradation at 20,000 miles that was indicated when I let my charging habits get lazy. I find the idea of being down 8% on range after only 12,500 miles to be unlikely, but I am not surprised this amount of degradation is falsely being displayed due to your charging habits.

Keith

I'm a fairly new Tesla owner, can you explain what the "foolishness/circus act" is?

 

[DanDi58]

So I am original owner of a 2018 M3P with 63k miles on it and a 2022 MYP (2170 pack) with 12,500 miles on it.

Both vehicles dropped range by almost 8% at about the 10-15k mark, despite the foolishness/circus act procedures trying to get the BMS to recalculate.

I have always charged to 90%, less than a dozen times on each vehicle gone to 100% for trips. Supercharge rarely. Almost never below 10%.

90% charge for my M3P has held pretty steady at 246
90% charge for my MYP is now a disappointing 251

SO, I was wondering if the 4680 MYLR deliveries out of Texas are seeing the same 8-10% loss by 15k miles?

Please tell us how you are measuring this "degradation" - simply by calculations, or by actually checking the battery pack with an OBD reader?

 

[AlanSubie4Life]

Please tell us how you are measuring this "degradation" - simply by calculations, or by actually checking the battery pack with an OBD reader?

These methods are exactly equivalent if your pack capacity is below the degradation threshold and you charge to a high SOC. There's no reason for an OBD reader if all you want to know is your BMS estimate of your battery capacity (the only measurement of your pack capacity that is available to anyone including Tesla). It (the OBD reader) is obviously useful for a bunch of other parameters and diagnostics but many people just want to know their BMS estimate (specifically % loss estimate), and that's readily available to everyone.

 

[DanDi58]

These methods are exactly equivalent if your pack capacity is below the degradation threshold and you charge to a high SOC. There's no reason for an OBD reader if all you want to know is your BMS estimate of your battery capacity (the only measurement of your pack capacity that is available to anyone including Tesla). It (the OBD reader) is obviously useful for a bunch of other parameters and diagnostics but many people just want to know their BMS estimate (specifically % loss estimate), and that's readily available to everyone.

True, as you say, if all you want to know is the estimate. But the way I read the OP's post is he is saying he thinks he has 8-10% battery degradation at 15k miles. I don't believe, based on everything I've watched and read, that you can tell true degradation unless you can look at the actual usable capacity of the battery, which some OBD readers can give you. TBH, I don't really care as I don't worry about it, personally. I just drive the car and charge when it tells me to, and overnight every day.

Bjorn covers the BMS aspect of this pretty well here.

 

[AlanSubie4Life]

ut the way I read the OP's post is he is saying he thinks he has 8-10% battery degradation at 15k miles.

This is the same thing as the BMS estimate of capacity loss. Of course it is an estimate, but there's nothing else available and it's what your car uses to predict whether you can make a particular destination (which is the only time this matters).

, that you can tell true degradation unless you can look at the actual usable capacity of the battery, which some OBD readers can give you.

This is available from the car. You just need one person with a brand new car of your car model (same year) to do the energy screen calculation to provide you the degradation threshold (which you can't know if you are already below the degradation threshold). Or you can do this yourself when the car is brand new as a baseline and record it.

It's true that to the extent the actual capacity of the pack when new exceeds the degradation threshold, there is some error in this calculation (you'll be calculating the reduction in estimated capacity from the degradation threshold, not from your original pack capacity), but typically this discrepancy is pretty small (just 1kWh or so, though it depends on the year and car model).

Once you have that degradation threshold, you just multiply it by the ratio of your full pack rated range to your original EPA rated range (FullPackRatedMiles/EPARatedMiles) to give you your current estimated pack capacity. (Or if you don't care about capacity you can just use the ratio directly, for the % remaining from original capacity.)

This will match the OBD reader exactly (the nominal full pack - usable capacity is 95.5% of this for Model Y & Model 3). Again, the OBD reader just gives you the estimate as well (the same one). It's an estimate, the best estimate, relied upon by the car.

 

[iamnid]

Agreed - doubtful there's 10% degradation. There are a million threads on here about how unreliable the "miles" display is on the battery. Anecdotally, I've seen it vary wildly from day to day on our Model 3. A few days of back to back charging up to 100% and then discharging to a very low percentage (e.g. 10% or so) will then show a much higher "range" in miles when charged back up. Nothing actually changed other than the number of miles the car thinks you can travel -- it isn't indicative of any real degradation. The BMS just seems to need to see the full range of your battery occasionally so that the "miles left" estimate can be more accurate.

On my Model Y I've had the display set to % since I got it but I'm sure I'd be seeing the same type of "miles left" shenanigans if I had the display set to miles and charged daily to see what it stopped at when set to 80% or 90%.

 

[AlanSubie4Life]

Bjorn covers the BMS aspect of this pretty well here.

Bjorn is basically wrong about this, just to be clear (I just watched the first couple minutes, so it's possible he clarifies later). In certain situations he's correct:

1) If Tesla changes the constant after shipping the vehicle, the method is invalid. This does happen, but is relatively rare - can happen early in model years. For Model 3 LR (2018), this is not one of those cases - the 310->325 came from an increase in the degradation threshold (not an increase in available capacity), but no change to the constant. In these cases you just use the new valid rated range number, though, which is easy to figure out. And you can of course easily tell if the constant has changed (it's readily available in the vehicle either on a very large charge event (>200 rated miles), or from the energy screen!) and you just have to be careful to use the right one. Best dealt with on a case-by-case basis but is the exception rather than the rule. E.g. This did happen for Model 3 2020 briefly (first deliveries were with 310 rated miles but quickly software updated to 322, 304, or 299).

2) There is not exactly hidden capacity above 100%. What it is is expansion of rated mile energy content when the available energy exceeds the degradation threshold. When you get to that point, the rated miles act sort of like a "percent" value, in that the max range of the car can represent a range of energies above the degradation threshold. As I said, this discrepancy (range of energies) is typically quite small. (This also may have behaved differently on Model S/X (they may have had hidden capacity above 100%), which is what Bjorn pictured, but is not relevant in this forum. Model Y and Model 3 will immediately start reducing their rated range as you drive even if you are substantially above the degradation threshold - they'll just tick off slightly more slowly than they would if you were below the degradation threshold, because the rated miles contain more energy. )

The ratio method will work and will match the OBD exactly (within the rounding error), as long as it is done correctly. This is well established; you definitely don't have to believe me; it's easy to verify if you have an OBD reader.

 

[AlanSubie4Life]

A few days of back to back charging up to 100% and then discharging to a very low percentage (e.g. 10% or so) will then show a much higher "range" in miles when charged back up. Nothing actually changed other than the number of miles the car thinks you can travel -- it isn't indicative of any real degradation. The BMS just seems to need to see the full range of your battery occasionally so that the "miles left" estimate can be more accurate.

Yes, and all of these changes will be reflected in the read back from the OBD reader, for your Nominal Full Pack. It will also be varying wildly as the BMS adjusts wildly. It's equivalent information. They always match.

(Obviously you ignore any rated range projections in the app when at low SOC for all of this. Just talking about 100% charge values (90% charge is close enough but will obviously have error). But the rated range projections in the app can be off by over 100 rated miles, as everyone knows. Just simple rounding error. Just wanted to be clear that's not what we're talking about here. )

 

[Ogre]

There is little expectation the current generation 4680 cells will be any less prone to degradation after a year of use. These first gen 4680 cells don't have any of the chemistry changes which were discussed on battery day so they are essentially a thicker version of the 2170 in all current Model 3/Ys.

Tesla will be improving the chemistry in these cells, likely fairly soon. But this first swag from Kato/ Fremont is same old stuff just bigger package.

 

[Fourdoor]

I'm a fairly new Tesla owner, can you explain what the "foolishness/circus act" is?

The key is for the car to sleep at different states of charge in order for the BMS to have a good handle on what the battery condition is. The two easiest methods of achiving this are:

Method #1. Don't charge to the same level each day, I cycle from 50% to 90% over a two week period, in 5% increments and then I cycle in the opposite direction for the next two weeks. You don't have to do this on a ridged schedule or anything, I just find the 5% increments to be easy to do.

Method #2. Only charge once every few days lettings the car sleep each night at a different charge level.

Keith