Model 3

Does driving habit/acceleration affect displayed Range (charging)

Have had my Model 3 since it first came out. Only about 13k miles. When I charge to 100% it says the max is 298 miles (down from 310), and on a daily charge (90%) it is only giving me 260 (down from 280).

A Tesla tech was over to fix something and when asked he mentioned that the battery was fine, but the cars display/computer was giving me a projected range based on how i drive (yes, i drive fast).

Anyone know if his recommendation is true?
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Comments

  • The battery meter range estimate is based on EPA rated efficiency (wh/mi). The energy graph will display your actual driving efficiency over the past 5, 15, or 30 miles.

    The battery meter range is just an estimate that will vary over time as it is influenced by other factors. It is not an indicator of battery health.

    You can also use the search function as this topic has been covered many times.
  • Probably Sentry mode is affecting displayed range. I was using Sentry mode for about 8 hours a day at work. Now I am mostly working from home and the range started increasing from ~290 to 300 over last 2 weeks. @38k mile.
  • > @gottafly said:
    > Yes

    You didn't get the memo did you?
  • What did the tech recommend?
  • > @GHammer said:
    > > @gottafly said:
    > > Yes
    >
    > You didn't get the memo did you?
    I guess not. Personal experience correlates perfectly w/ Mobile Tech statements. I’ll try not to be too long winded.

    M3 owner for 1 1/2 years. 33k miles on the odometer. First full year of driving (pre-Covid) included lots of highway miles and average daily round-trip to work of 120mi. Average speed on commute (rural hwy) approx. 65mph. Average highway speeds 75-80mph.

    Noticeable “degradation” in estimated range, from 315mi when new to 287mi at 100% (Approx 9% decrease in range) over the course of the first year. However, in the last 6 months, my commute has all but ceased, and the car has been driven locally, almost exclusively. Average speed during this period, probably around 35-40mph.

    Guess what? The estimated range has actually increased, now reading approx. 297mi at full charge. How could this happen, unless Telsa is using a “rolling average” of most recent driving style/speed/habits.
    Look, no one know exactly HOW the software is calculating the estimated range or what factors are being used and how those factors are being weighed, but obviously it is not a static figure or a linear result based on EPA rating or such. YMMV (literally).
  • Green bar is not degradation meter it is estimated range based on many factors.
  • > @WW_spb said:
    > Green bar is not degradation meter it is estimated range based on many factors.

    Correct. That is why I put “degradation” in quotes.

    And the green bar is what many people seem to reference when they state that their battery range/capacity is diminished. Rather, it is attempting to display the expected range based on a number of factors as mentioned above.
  • @gottafly "Look, no one know exactly HOW the software is calculating the estimated range or what factors are being used and how those factors are being weighed, but obviously it is not a static figure or a linear result based on EPA rating or such. YMMV (literally)."

    Here's their patent on how they calculate the estimated range. It notes that over time, it can be subject to calibration issues due to rounding on the voltage measurements and periodically needs to relearn what is "full" through actual charging.
    https://patents.google.com/patent/US8629657B2/en
  • There are too many variables affecting the projected range to use that solely as the measure of battery degradation over time. Weather factors, driving speed, etc., all affect it. Sometimes I will drive the battery down to recallibrate, but it's an estimate, not a direct measure
  • @gottafly
    Have more than ten times as many miles on the odometers, and I respectfully disagree. I'ver written volumes on the subject over the last 7 years. Hence the "No" that preceded your "Yes." The rate constant converting stored kWhs to rated miles does not change based on driving habits. Range estimates vary based on a fundamental inability to measure pack charge accurately. Inaccuracies can be magnified by charging habits, less so driving habits. Regardless, your driving efficiency history does not impact range estimates.
  • Bighorn, why my estimated range keep on going up but my charging habit is the same? 50to70.
  • Is it possible they adjusted the formula for how it's calculated?
  • > @WW_spb said:
    > Bighorn, why my estimated range keep on going up but my charging habit is the same? 50to70.

    Software updates can help with resetting the calibration. I often notice a bump for a few weeks shortly after an update even with no other changes. Other times I see an increase are after a longer road trip, where I use a larger portion of the battery in a single drive, and then charge immediately when completed (so minimal idling losses).
  • Estimated range is guesstimated range. Looking for patterns is futile. As @hokiegir1 points out, firmware updates can sometimes recalibrate the estimate. Mine has gone down and up and down irrespective of charging or driving behavior. It's the way of the BMS. What's clear is that the rate constant does not change. Years of data corroborate this truth.
  • Sounds like your cars range estimator is correct. The more inefficiently you drive, the less range you will get out of your battery. Same as any car.
  • @andy_connor_e
    True statement, but not the subject of this post.
  • "A Tesla tech was over to fix something and when asked he mentioned that the battery was fine, but the cars display/computer was giving me a projected range based on how i drive (yes, i drive fast)."

    Not really a recommendation, but the tech is correct. Battery is fine, and projected range is based on how OP is driving.
  • The energy graph gives the only realistic range estimate in a Tesla. The Range number is fairly useless. Every other EV has a guess-o-meter there which does reflect how you are driving, Tesla's number is just the battery level multiplied by the EPA number. It's better to keep that display on percent, because that's all it really is, and use the Energy Graph for a real range estimate.
  • > @bjrosen said:
    > The energy graph gives the only realistic range estimate in a Tesla. The Range number is fairly useless. Every other EV has a guess-o-meter there which does reflect how you are driving, Tesla's number is just the battery level multiplied by the EPA number. It's better to keep that display on percent, because that's all it really is, and use the Energy Graph for a real range estimate.

    That agrees with what Tesla support says: "Displayed range in your Tesla is adapted based on fixed EPA test data, not your personal driving patterns." But then it continues "It’s natural for this to fluctuate due to the nature of battery technology and how the onboard computer calculates range." I don't understand what is "natural" about range fluctuations. EPA (based on Tesla testing) reports 26 kWh/100mi for my original run 2018 Model 3 LR RWD. If the calculation is based on that number does that mean the energy in the battery fluctuates even for the same state of charge? I.e. One day I charge to 100% and range is 288. Next day it's 284, or 280? What changed?

    We have about 40k miles on our Model 3. It now reports ~288mi for a full charge, so about 7% loss from original 310 miles. We just drove round trip LA to Chicago. ~ 4k miles over 5 days driving (we stayed a couple of weeks so not an insane 5 straight days of driving). My actual energy usage varied a lot depending on the normal factors. But my reported "charge range" also varied. No too much, but some. For example, on our first day battery total reported range was 1,277 miles and energy used 281 kWh. Thus our "range factor" was 220 Wh/mi (or 22 kWh/100mi as EPA likes to use). I understand why it reports more efficient than the EPA 260 kWh/100mi because EPA number is from the wall and counts charger loss. But what I'm don't understand is the fluctuation, even if it's not too big: the other four days were 222, 220, 223, 233. Why any difference? Is there some hidden EPA data we're not privy to? Does battery reach a slightly different SOC based on how it's feeling at the moment?
  • @eric_98131544 The Tesla patent for their Battery Management System (BMS) notes how the system will take a measurement from each cell to determine it's capacity. But each time this measurement is taken, there's a small amount of rounding that occurs. So, every time, there are just shy of 3000 rounding variances happening. Then, the next time it measures, it's going from the last measurement to the current one -- so it's compounding that rounding difference. So while it's a constant that is being multiplied, the measurement part can vary. This is why occasionally you will see it go back up, especially after longer drives. Certain actions make the measurement more accurate -- so you can "regain" some lost range because it has fewer rounding errors.
  • > @WW_icefree said:
    > Green bar is not degradation meter it is estimated range based on many factors.

    What factors? Tesla support specifically says it's based on EPA numbers and not driving habits. They also say it's "natural" to fluctuate. Is this corporate double-speak? Is there some magic hidden EPA data Tesla doesn't want us to know?

    Sometimes it feels like it changes with temperature, but on my recent trip there was no correlation with temps.

    If reported range loss is not a measure of degradation what is? What makes me lose 7% of my range -- 310 to 288 at 100% charge?
  • > @eric_98131544 said:
    > > @WW_icefree said:
    > > Green bar is not degradation meter it is estimated range based on many factors.
    >
    > What factors? Tesla support specifically says it's based on EPA numbers and not driving habits. They also say it's "natural" to fluctuate. Is this corporate double-speak? Is there some magic hidden EPA data Tesla doesn't want us to know?
    >
    > Sometimes it feels like it changes with temperature, but on my recent trip there was no correlation with temps.
    >
    > If reported range loss is not a measure of degradation what is? What makes me lose 7% of my range -- 310 to 288 at 100% charge?

    You didn't lose much all you need is recalibration. My M3 past year has been all over the place 310 then down to 296 then back up to 302, 306 then down again.
  • > @WW_icefree said:
    > > @eric_98131544 said:
    > > > @WW_icefree said:
    > > > Green bar is not degradation meter it is estimated range based on many factors.
    > >
    > > What factors? Tesla support specifically says it's based on EPA numbers and not driving habits. They also say it's "natural" to fluctuate. Is this corporate double-speak? Is there some magic hidden EPA data Tesla doesn't want us to know?
    > >
    > > Sometimes it feels like it changes with temperature, but on my recent trip there was no correlation with temps.
    > >
    > > If reported range loss is not a measure of degradation what is? What makes me lose 7% of my range -- 310 to 288 at 100% charge?
    >
    > You didn't lose much all you need is recalibration. My M3 past year has been all over the place 310 then down to 296 then back up to 302, 306 then down again.

    I've heard recalibration is fully charge then fully discharge. Is that what you mean? And this would only fix the range number, not actually change how far I can drive, right? (I.e. is it really worth doing?)
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