Model 3

A letter about range from Tesla

edited December 2019 in Model 3
A member of our local Tesla group got this mail from Tesla.
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Hello XYZ,

I am reaching out today in regards to your upcoming appointment with Tesla Service. I work with Tesla's Virtual Diagnostic Team in which our goal is to proactively pre-diagnose your vehicle prior to your service appointment and order any parts if needed in an effort to make your service experience as fast and as seamless as possible. We have already started work on your vehicle remotely. I am currently reviewing your service visit scheduled in Tysons Corner for 12/##/2019 at 2:00pm

Regarding your concern: “My total range is 305, why has it dropped after a full charge”.

Results:
· First, I want you to rest assured that your HV battery pack is happy and healthy.
· Comprehensive remote diagnostics results in no hardware issues to address.
· Your battery capacity tests are that your pack is 0.1% HIGHER than the avg of similar configured vehicles.
· Driving higher than the normal EPA rated consumption rate, lower ambient temperatures and charging habits affect projected miles calculation, not actual battery capacity.
Specific details:
I have done comprehensive remote diagnostics on your vehicle. High voltage system remote diagnostics returns no hardware issues on your vehicle that needs to be addressed. I have compared your vehicles ability to store energy as compared to all other long range rear wheel drive Model 3s and your vehicle’s energy storage capacity is slightly above the average of the fleet. Your vehicle displays no alerts indicating hardware issues. This shows that the battery is retaining energy properly.

I have reviewed the energy consumption of your vehicle and the consumption rate over the last 30 miles is 284.4 Watt Hours per Mile which is what the vehicle actually uses for projected miles calculations. When EPA set the range and consumption standards for your configuration vehicle they rated the consumption at 234.0 Wh/mi during testing. The effect of operating at higher than the rated consumption is that projected miles will decrease faster than actual miles driven and also cause projected miles to be under calculated slightly. You can monitor rated, average, and live energy consumption numbers on your energy graph of your center display. This is one factor in why your projected range will show lower than expected.
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Comments

  • edited December 2019
    As in all Lithium Ion batteries there is a small initial capacity loss early in the beginning of the battery’s life cycle. This well documented characteristic exists in everything that utilizes Lithium Ion technology as a power source such as cell phones, smart watches, electric vehicles, etc. The initial capacity loss is very small at 1 or 2 percent. After this initial drop in capacity, the best characteristic of Lithium Ion technology is that capacity loss rate plateaus to a very slow rate of loss. Your vehicle (as does all electric vehicles) has experienced this initial capacity loss and has reached the capacity plateau where we expect the rate of capacity loss over the life of the pack to be at a slow rate. As stated, your battery capacity tests slightly higher than the fleet average.
    Background:
    Some our customers worry that when the projected miles shown on the display fluctuate or show lower than it did previously, especially in colder weather, that something is wrong with their battery pack. Battery capacity plays a very small role in what goes into calculating what is shown as the projected miles until depleted. Your question of the projected miles fluctuating is a normal and expected operation of the vehicle and is not an indicator of deteriorating battery health.

    Projected miles is only meant as a rough estimation of distance until discharged. A decrease in projected miles is not a direct indicator of deteriorating battery health as there are many other variables involved in calculating the projected miles. Projected miles is an algorithm based on several factors such as calculated battery capacity, current energy consumption rates and environmental data just to name a few. Battery capacity data cannot be directly measured from the battery pack, therefore it is calculated by the battery computer. To determine projected range the battery computer will start with the calculated capacity of the battery pack, modify that number by figuring in recent energy consumption to predict future energy consumption, then modifying the algorithm further with environmental data such as ambient temps before outputting a projected mileage number. As you can see the actual calculated battery capacity is only a small part of what is shown in the projected mileage. Since the projected miles calculation is influenced by consumption rates and environmental elements, it cannot be considered solely as an indicator of battery health. Variations in projected range is expected even at full charge due to all of the variables described. Environmental variables like temperature and energy consumption habits will always fluctuate therefore the algorithm and displayed output will as well. Our engineering team works constantly to refine the projected mile algorithm to be more accurate considering all of the variables involved. You receive these updates via firmware periodically.
  • edited November -1
    The projected miles algorithm is heavily affected by temperature swings. Due to battery chemistry, all batteries in general are less efficient in colder temperatures. They release energy slowly, accept energy slowly, and also will have slightly less capacity level when cold. The projected miles algorithm attempts to account for this in the displayed projected miles and will show less projected miles. In warmer weather these effects are reversed and we typically see that projected mileage deficit return in warmer weather. This is also why battery heating occurs in the background, not only to save the battery from damage, but to help keep the batteries more efficient.

    Since monitoring projected miles is not a good way to judge battery health, and when we want to evaluate the health of your battery pack, there are two main tools that we use to evaluate battery health remotely in concert with the onboard diagnostics that run constantly on the battery computer which continuously monitors battery health. We will run a comprehensive hardware check remotely on the vehicle analyzing the vehicle logs for many possible issues. In addition we have the ability to check and compare your specific battery capacity to that of the rest of the worldwide fleet of similar configured vehicles in real world conditions to see your particular vehicle does have problems with energy retention. We report these results to you above. Another step we may perform is a manual log review usage and charging patterns to asses if we can give tips on maximizing projected range. There are some winter tips below.

    We understand that you are very concerned about your battery health and are happy to look into the matter for you when you feel something may be wrong. However please be confident in your vehicle’s ability to self-report any hardware issues that it detects in your vehicle. When a hardware problem is detected, there will be accompanying alerts and messages displayed on the center display requesting you take the vehicle into service if that were the case. The battery monitoring system is very aggressive at monitoring and reporting any battery hardware errors that it senses to occur. These alerts typically would present in a message that pops up on the screen indicating that the vehicle needs service. Alternatively, many customers prefer displaying the battery state of charge (much like how your cell phone works by displaying battery %) because the battery state of charge is directly measured from voltages in the battery pack and is more direct indicator of battery health. If your battery is healthy and charge termination set at 100% the battery should be able to achieve 100% at the end of charge. If it does not, we’d suspect a possible hardware issue.
    Additional Information:
    In colder climate we recommend leaving the vehicle on the charger while not in use. As colder weather approaches, the vehicle will be doing more in the background to heat and condition the battery pack as the vehicle sits idle. I have verified that your vehicle has had active battery heating active periodically. We recommend leaving the vehicle on the charge cord if maximum projected miles is needed for your drive cycles. This utilizes wall power to heat and condition the battery instead of battery capacity. Another useful tip is to precondition the cabin using the app while it is still plugged into wall power as to utilize wall power rather than battery capacity before you leave for the day. If the vehicle is not plugged in with colder weather, battery capacity will be used for background functions and when you enter the vehicle the next day, you will notice less projected miles then when you left the vehicle prior. We expect to see less projected miles displayed in colder weather based on this and for the miles to return in warmer weather based on the environmental variables affecting the projected miles algorithm. This is not indicative of battery hardware issues and is expected across all electric vehicles.

    To reduce energy consumption during the colder months consider favoring the seat heaters over cabin heating. The seat heaters will utilize a fraction of the energy that active cabin heating does. So many customers elect to turn down the cabin heating to the minimum comfortable level and utilize seat heaters more. They have reported that no comfort has been compromised.

    In summary, your fluctuation of projected miles is not a result of battery hardware issues. This being the case, service intervention and your appointment at the service center is not needed. In interested of saving your time, I’m happy to cancel your service visit for you if you’d like.

    I hope I’ve helped answer your concern on your vehicle and I have answered any questions you may have. If not, I’m happy to follow up with any additional questions you may have.

    Thank you,
  • edited November -1
    Nothing we didn't already know.
  • edited November -1
    What all common sense people already know. Thanks
  • edited December 2019
    It is, but it’s helpful for all the people who keep insisting and asking. So thank you!
  • edited November -1
    Wow, that’s quite the letter!
    Good info, good formal confirmation.
  • edited December 2019
    Why doesn't the person who got the personal letter post it?
  • edited November -1
    It feels like they cheated off my paper down to the 234 Wh/m.
  • edited December 2019
    +1 Bighorn Sounds like everything I learned from the early owners.
  • There are some things in there that I do not believe were across the board common knowledge - like your individual car's driving history tailors the SOC estimate, rather than it being a [projection of the EPA basis. I like this better - this way SOC estimates better suit the season, and the evolution of a driver's habits.

    It's also good to see "official" validation of 234 being the EPA ranger basis.

    Thanks for posting this vmulla.
  • edited December 2019
    "like your individual car's driving history tailors the SOC estimate, rather than it being a [projection of the EPA basis. I like this better"

    I dont think that's what the letter says. It says "projected" miles is influenced by driving and environmental factors.
  • edited December 2019
    Some of the response sounds like baffle them with BS. If driving style really affects it why is it when my lifetime wh/mi goes down does my estimated miles also go down? Also seems like 284 would cause a much lower estimate than 305. But since we will never know the actual algorithm, will be difficult to pin down.
  • GHammer, it sounds like you agree with me.
  • edited December 2019
    OK, I thought you were saying "rated" SOC miles changed with environment and driving history.
  • edited December 2019
    Tesla needs to have an info (i) icon in the Wh/mi and energy report to explain range and efficiency expectations. Maybe even a Battery health report like Apple provided for iPhones. Rather than us all emailing Tesla, Tesla could make this information readily accessible inside the car!
  • edited December 2019
    As an Engineer I fully understand the lifecycle of Li Batteries, however I disagree somewhat with vmulla. My Model 3 showed the initial degradation of range within a month after I bought it (310 miles down to 304 miles) after about a month at 100% SOC.....it stayed roughly there for a year, but a year later exactly when I downloaded 2019.32.12.2 I noticed what appeared as a loss of range. At 100% SOC it now only showed 294 miles. I ran several charge tests I did all of the gimmick "re-calibrate the batteries" suggestions here on the forum and no change. I scheduled a service visit and they sent the ranger to my house and he "ran the diagnostic" and basically gave me the same response the OP got in his letter. Bottom line, something changed when I installed 2019.32.12.2 and it affected the range calculation and it happened overnight which is not a characteristic of a Li Battery loosing it's capacity. Check the forum. A lot of other posters noticed the same phenomenon with 2019.32.12.2.
  • edited December 2019
    For those still watching/reading at this point I'd like to inform you that the individual named as fishev in this thread is a super long term infestation troll who has been banned at least once (as EaglesPDX) for spreading utterly false and defamatory things about Tesla and for being a liar.

    Please Flag and ignore any and every single thing they post. Don't respond if you can avoid it.
    Thanks!
  • edited December 2019
    I re-read the post from vmulla and I see now what he was trying to point out (apparently a response from Tesla) . Wasn't trying to dispute him in anyway but I did initially mis-read his post. None the less, something changed with 2019.32.12.2 and Tesla hasn't been forthcoming with what changed or why. There was some speculation that they limited the charge in response to pressure regarding fires but I don't necessarily buy that rationale.
  • edited December 2019
    This post should be pinned at the top of the forum. A very good read and correlates well with my experience. I have not charged to 100% ever and have made both extended supercharger trips and spent months on either a 120V or a 240V charge cycle. Today I looked after charging to @80% it showed 245. Pretty insignificant change from 248. I do all my calculations based on a 310 range as that is what I bought when the car was new.
  • edited December 2019
    @walnotr mine at 80% shows 236, used to be 248 until 2019.32.12.2
  • edited December 2019
    310 as a range number is nominal in nature. We all know a RWD Model 3 is more efficient than an AWQD, but both had the same basis. My LR AWD at less than 15 miles showing only ever charged to 306 @ 100%, so I use that as the baseline for my car. 14 months and 21.5k miles later, 100% charge shows a 296 mile estimate. A 90% charge, which I use routinely, was 278 miles and is now 266. I noticed that the drop began showing up in the early summer, and settled into where it is now in sept-oct.

    This represents approx. a 3.3% loss of capacity. This is in line with what I've read about Tesla batteries, both in amount of loss and in the timing, or when in the aging process it happens. Next, I'll see if my experience matches up with the next expectation - that this capacity loss stays at the current plateau for an extended period before losing any further noticeable capacity.

    Also in line with expectations somewhat referred to in the warranty. I have no reason to think anything is out of the ordinary with my experience.

    Sometimes software updates might change how that estimate is arrived at, and therefore might present an inaccurate picture of how your battery changes. An overview is more useful here than getting granular. The overall trend has meaning, a software update not so much.
  • edited December 2019
    Keep in mind that every single thing fishev posts is a dissembling lie and that they have been banned here before in other guises.

    Pay no attention to them and please do us all a favor and click the Flag as Inappropriate button at the bottom right of their posts.
    Thanks and enjoy your M3.
  • edited December 2019
    Great standard response John. Every single post is a lie.
  • edited November -1
    I agree that temperature impacts the range estimate. I disagree that driving style does. I have my knseves any change to range correlated to my driving style. Some days I average 230, other days 250, and some 400 wH/mile. I have never observed a positively correlated change. We have many examples of Tesla employees saying exact opposite things as truth on the same subject.

    The biggest driver is changing range forecast? Depth of discharge and charge. Drive down to 30% and charge to 90% if you want more accurate estimates.
  • edited December 2019
    @bigroccrek - as I don’t keep my display set to miles, I have not noticed any appreciable reduction in range with any update. The only time I bother looking at the mileage is when the forum blows up about range loss. My experience has been nominal range loss as mentioned above. When we picked up the car we asked for a 90% charge and it showed 279. After a few weeks charging on a 120V circuit, it was showing 272 and stayed pretty consistent. A month or two later we did a 3000 mile road trip using superchargers exclusively and surprise, the rated miles were back at 279. After that I switched over to percent and never looked back. With all the anxiety around this, I checked the “mileage” again about 4000 miles into our last trip and 90% was at 278. The bottom line is, the numbers change up and down depending on charge cycles and driving style. As they say YMMV.

    Back to the top.
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