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Kinda disappointed that I have 5.5% degradation after 18k miles

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Are you actually getting that range or is that just what is indicated on the screen?

Just what is on the screen. I never have used more than 60% the displayed capacity, or 143 miles, even on 4000 mile trip. So my actual range would be pretty close to what is advertised, but my consumption is low at 285 Wh/mi.

The screen rated range says 265. But it uses Total capacity, including the 4Kwh buffer. My Usable capacity per CAN bus is 71.5, down from 77.5 when new. So at 292 Wh/mi of EPA consumption, about 240 miles of Rated Range down from 270 new.
 
How reassuring :(:(:(
It’s what the range on the screen is showing.
The displayed range is what shows whether or not you have degradation. The range displayed is based on a simple calculation: (Remaining battery capacity in Wh) ÷ (EPA Wh factor). The EPA Wh factor should not change, that was determined at time of EPA testing. If numbers are going down, that means remaining capacity is decreasing either through usage or degradation. If you don't regularly charge to 90%, then it might be a good idea to charge to 90% occasionally to ensure the algorithm is properly calibrated.
 
Just what is on the screen. I never have used more than 60% the displayed capacity, or 143 miles, even on 4000 mile trip. So my actual range would be pretty close to what is advertised, but my consumption is low at 285 Wh/mi.

The screen rated range says 265. But it uses Total capacity, including the 4Kwh buffer. My Usable capacity per CAN bus is 71.5, down from 77.5 when new. So at 292 Wh/mi of EPA consumption, about 240 miles of Rated Range down from 270 new.
The discrepancies between the indicated range and what I really get is the main reason I switched to percentage display rather than miles remaining.
 
The displayed range is what shows whether or not you have degradation. The range displayed is based on a simple calculation: (Remaining battery capacity in Wh) ÷ (EPA Wh factor). The EPA Wh factor should not change, that was determined at time of EPA testing. If numbers are going down, that means remaining capacity is decreasing either through usage or degradation. If you don't regularly charge to 90%, then it might be a good idea to charge to 90% occasionally to ensure the algorithm is properly calibrated.
There are other variables to the range calculation. It's a common for people to think that it's a simple calculation (misinformed people at Tesla don't help) but there are other things that affect that number.
 
As far as rated range consumption, it is a tested constant.

The battery temp, the speed/power, the cell balance, and the BMS calibration can affect the actual capacity, and therefore range. The temp is maybe a percent or two, the rest are probably small as well.
 
There are other variables to the range calculation. It's a common for people to think that it's a simple calculation (misinformed people at Tesla don't help) but there are other things that affect that number.
Please enlighten the community as to the "other things" that affect that number?

The only "other thing" that I'm aware of is temperature fluctuation. That is still part of the remaining kWh calculation. No matter how you slice it, rated range is remaining Wh (calculated by BMS) ÷ EPA constant. The first part of the equation may fluctuate depending on environmental conditions, and that is caused by internal resistance, but the 2nd never changes.

It is a simple calculation that does not deviate much unless the vehicle is subjected to temperature extremes.
 
Please enlighten the community as to the "other things" that affect that number?

The only "other thing" that I'm aware of is temperature fluctuation. That is still part of the remaining kWh calculation. No matter how you slice it, rated range is remaining Wh (calculated by BMS) ÷ EPA constant. The first part of the equation may fluctuate depending on environmental conditions, and that is caused by internal resistance, but the 2nd never changes.

It is a simple calculation that does not deviate much unless the vehicle is subjected to temperature extremes.

I tend to agree. Although we may never fully understand how the BMS is programmed, for my car I can say the capacity seems to not vary much, 1-2 KwH at most, despite temp and charge and storage changes...

However, actual capacity of my pack shows twice the degradation compared to the RR (Rated Range). That is a concern.
 
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Please enlighten the community as to the "other things" that affect that number?

The only "other thing" that I'm aware of is temperature fluctuation. That is still part of the remaining kWh calculation. No matter how you slice it, rated range is remaining Wh (calculated by BMS) ÷ EPA constant. The first part of the equation may fluctuate depending on environmental conditions, and that is caused by internal resistance, but the 2nd never changes.

It is a simple calculation that does not deviate much unless the vehicle is subjected to temperature extremes.

The way I understand it is that the BMS only reports what it sees.

OP said he charges the battery to 70%.

If the battery isn't charged and discharged all the way, the BMS can only guesstimate the capacity, so OP's degradation could be less than what he thinks.
 
The way I understand it is that the BMS only reports what it sees.

OP said he charges the battery to 70%.

If the battery isn't charged and discharged all the way, the BMS can only guesstimate the capacity, so OP's degradation could be less than what he thinks.
my normal practice is to charge nightly to 70% @60A. I have discharged the car to 20% and charged to 100% to "reset" the BMS algorithm but it didn't seem to help much. I might try charging every other day which would be 20-80% to see if it changes. If not, oh well... battery degradation is to be expected, and it seems like it's random who sees minimal degradation and who sees more degradation. Just hoping this levels off....
 
Please enlighten the community as to the "other things" that affect that number?

The only "other thing" that I'm aware of is temperature fluctuation. That is still part of the remaining kWh calculation. No matter how you slice it, rated range is remaining Wh (calculated by BMS) ÷ EPA constant. The first part of the equation may fluctuate depending on environmental conditions, and that is caused by internal resistance, but the 2nd never changes.

It is a simple calculation that does not deviate much unless the vehicle is subjected to temperature extremes.
Except that anyone can manipulate the number simply by taking a long road trip and having the running average consumption go down. I have personally seen it dozens of times in the various Teslas that I have owned and driven and I'm not the only one.
 
Except that anyone can manipulate the number simply by taking a long road trip and having the running average consumption go down. I have personally seen it dozens of times in the various Teslas that I have owned and driven and I'm not the only one.

Not sure what you are referring to exactly, but rated miles are always calculated based on nominal full pack and a constant, along with current SOC%. The formula is: Rated miles = SOC x (nomfullpack)/constant. It can be verified easily by looking at TM-Spy or Scan My Tesla readouts.

Maybe you can show some data from your car to explain what you are describing, which I think must be something different.
 
Not sure what you are referring to exactly, but rated miles are always calculated based on nominal full pack and a constant, along with current SOC%. The formula is: Rated miles = SOC x (nomfullpack)/constant. It can be verified easily by looking at TM-Spy or Scan My Tesla readouts.

Maybe you can show some data from your car to explain what you are describing, which I think must be something different.
For example: 90% charge shows 225 miles of range. Take a 1000 mile road trip and lower your indicated running average consumption by x amount. Now your 90% charge shows 227 miles of range.
 
Weirdly my pack (early 2016 90D) has gotten slightly better in the 11 months that I've owned it (when I got the car, 277 was the norm, now it is ... 278)

Practically speaking, the there are 3 kinds of trips you'll take with the car -- trips where you aren't going to use a supercharger, trips where you'll use a supercharger once, and trips where you're visiting more than one supercharger.

Here's an example of being "on the bubble" (a trip that's either a no stop or a 1 stop):

For my car, I can't drive a "reasonable" 220 mile round trip -- from boston to wellfleet, putter around all day, and drive back, unless I fill the car to 100%; if I fill it to 100% I'm projected to get home with 3-5%. A gasser or a newer tesla could (probably) do this trip and finish with a reasonable buffer.

So -- that kinda sucks because now the trip that would otherwise be entirely without thinking about range is now affected by "should I charge to 100% and risk it? Should I try to get my wife to eat at a place near the supercharger station? Should we just eat at the place we'd normally eat and hit a supercharger closer to home on the way back and grab coffee / bathroom break?" But from a practical perspective, it adds about 20 minutes to the trip and not a huge cognitive load.

On longer trips, you're typically bouncing between 10% charge and 60-70% charge, the range where the car charges fastest. And if you get a station that charges slowly, or if your car charges slowly everywhere, it just kinda stinks because the stop becomes a 45+ minute ordeal instead of a 20 minute stretch.

So, from *my* experience, there simply isn't much difference between 280 and 250 miles of range because any trip greater than 200 miles will almost certainly include at least one supercharging stop.

The real question you should ask yourself is how fast does your battery charge?
 
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Except that anyone can manipulate the number simply by taking a long road trip and having the running average consumption go down. I have personally seen it dozens of times in the various Teslas that I have owned and driven and I'm not the only one.
No... Your average Wh/mi consumption over time does not affect this calculation in the slightest. My average consumption has varied over 104,000 miles between the low 300s and high 260s and I've never, ever seen my estimate range increase as my average consumption over time decreased. My estimated range has only gone down since new. I regularly charge from 20% to 90%. No effect. No amount of "calibration" cycles changes my estimated range by more than a mile.
 
No... Your average Wh/mi consumption over time does not affect this calculation in the slightest. My average consumption has varied over 104,000 miles between the low 300s and high 260s and I've never, ever seen my estimate range increase as my average consumption over time decreased. My estimated range has only gone down since new. I regularly charge from 20% to 90%. No effect. No amount of "calibration" cycles changes my estimated range by more than a mile.
Whatever man. I'm not going to argue about facts that I and others have seen and repeated time after time for years. Every Tesla I have owned and driven for any period of time has had it's indicated range go up and down in a predictable and repeatable way.
 
Whatever man. I'm not going to argue about facts that I and others have seen and repeated time after time for years. Every Tesla I have owned and driven for any period of time has had it's indicated range go up and down in a predictable and repeatable way.

Ok, so your "Range might vary"

I think we can appreciate that rounding errors due to lack of significant figures, plus temp variations in the pack due to ambient or internal temps due to power draw, plus recalibrations performed by the BMS, can cause RR to vary by a few miles.

Just look at Teslafi, and see the ranges of the cars similar to yours. You can see the RR vary with time.

However, I am not OK with the range algorithm being intentionally dishonest by using full nominal capacity including the buffer, to display a RR, than cannot be achieved, even on a new car, without using the buffer.

I don't want people making fun of my car a la Delorean, in 5 years. Elons behavior of late is about one bad drug deal away from making this dismal reality.
 
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