Wiki Sudden Loss Of Range With 2019.16.x Software

[wk057]

To carry that thought forward a bit farther the software that was looking for X assumed X was really bad and took drastic measures, like limiting max voltage and all that. Hopefully we will see an update that properly detects and responds to Z proportionately to it's risk. If my understanding is correct that would return some range to those that have lost it as Z is less of an issue.

I guess to clarify a little more: The mitigation in place meant to combat X does also effectively mitigate Z. However, Z should get a more refined mitigation than is required for X.

I personally wouldn't consider X or Z to be "normal degradation." Tesla seems to recognizes that X would not be normal. Jury is still out on Z at the moment, on Tesla's side, with a proper detection correction. A proper mitigation of Z shouldn't be nearly as noticeable, in any case, so may be a non-issue... not really sure how that'll eventually pan out.

Edit: If you're lost: Sudden Loss Of Range With 2019.16.x Software and Sudden Loss Of Range With 2019.16.x Software

Edit: Oh, another interesting thing is that they do seem to care about Z. I specifically asked why don't they pull the update until they can get a better grip on the situation, and was told that if the update is protecting owners as it is, "we'll deal with it" in order to keep safety first.

 

[AmpedRealtor]

Range and charging speed is everything for an EV. Imagine if you owned a Merc or Jag and that legacy automaker coming to your home, taking the motor out and installing a smaller motor that gets worse gas mileage, less performance and installing a smaller orifice filler neck on the fuel tank that takes 15 minutes longer to fill at a gas station...……..what would you do?

If I had happily been enjoying the car for several years but then it became at at risk of catastrophic failure and they gave me choice to do that for free or replace the original engine for around $20K I'd consider my repair or replace options as I would for any car facing major breakdown. It happens all the time.

Imagine if you owned a Merc or Jag. One day, without your consent or knowledge, your dealer removes 10% of your gas tank capacity in order to make the gas tank last longer instead of replacing your gas tank with one that works properly. That's what is happening here. I don't think many owners would put up with that.

I guess to clarify a little more: The mitigation in place meant to combat X does also effectively mitigate Z. However, Z should get a more refined mitigation than is required for X.

I personally wouldn't consider X or Z to be "normal degradation." Tesla seems to recognizes that X would not be normal. Jury is still out on Z at the moment, on Tesla's side, with a proper detection correction. A proper mitigation of Z shouldn't be nearly as noticeable, in any case, so may be a non-issue... not really sure how that'll eventually pan out.

Edit: If you're lost: Sudden Loss Of Range With 2019.16.x Software and Sudden Loss Of Range With 2019.16.x Software

Edit: Oh, another interesting thing is that they do seem to care about Z. I specifically asked why don't they pull the update until they can get a better grip on the situation, and was told that if the update is protecting owners as it is, "we'll deal with it" in order to keep safety first.

Would I be wrong in assuming that X=li-ion plating (less dangerous condition) and Z=active dendrite formation (high risk condition for internal short)? Seems that li-ion plating, on its own, is not dangerous but does lead to loss of capacity over time. If li-ion plating is not managed, over time it leads to formation of dendrites. When those get long enough, the anode and cathode can come into contact and cause a short circuit inside the cell. Maybe this is what caused several parked vehicles in the last couple of years to catch on fire.

 

[DJRas]

I don't agree here, because every buyer knew that there will be battery degradation.

Tesla didn't know in advance how large real degradation including keeping battery safe, will be in the future. Up to now their capacity calculation did only capacity degradation take into account that appears at 100 % charging to 4.2 V. It now appeared that depending on usage by the users excessive lithium plating happened, which finally can cause battery fires. Through the new measures they make this cells safe again.

As the warranty says nothing about degradation, the batteries are still working and may so safely for hundreds of thousands of miles in the future, IMHO there is just no case.

Again you are ASSUMING this is due to Lithium Plating that can cause fires.
Tesla is SPECIFICALLY stating that this is NOT related to fires.
I agree that Tesla may not have known what the real degradation would be 5 years ago.
BUT, they had so much confidence in their batteries and the BMS that they issued the 8 year unlimited mile warranty.
This implied that THEY believed these batteries and their software are solid for 8 years of standard use.
This was also sold with cars with UNLIMITED lifetime supercharging.
Thus driving the car in whatever weather condition and supercharging as much as you want is NOT abusing the battery and "normal gradual loss of capacity" (wording from the warranty) can be expected.
THIS is NOT gradual loss of capacity but Instantaneous with a software release.
You have ZERO evidence that these changes make the batteries SAFE again.
The fire in Hong Kong was NOT during or immediately after charging. (which brought about their statement about software update to address the issue).
So, why are they limiting SOME batteries?
Where is independent review or oversight that this change does make the batteries safe for hundreds of thousands of miles?

The current high miles car is a Model S P85 with 900,000 km (559,000 miles). It had its battery replaced (under warranty once).
Why won't they replace my battery that has only 136,000 miles?
ESPECIALLY if they have determined through some BMS data that MY battery is in danger of bursting into flames while parked in my garage!

 

[AmpedRealtor]

The current high miles car is a Model S P85 with 900,000 km (559,000 miles). It had its battery replaced (under warranty once). Why won't they replace my battery that has only 136,000 miles? ESPECIALLY if they have determined through some BMS data that MY battery is in danger of bursting into flames while parked in my garage!

Because if they do it for you, they have to do it for everyone. What does a battery pack cost Tesla to manufacture and install? That could get very expensive.

 

[mjmiron]

This change has not only reduced my usable mileage and increased charging time. But it is actually costing me money because I can no longer drive with a buffer. I travel all over the state and sometimes I need the extra range, especially in winter which is coming up quickly. I don't have a dollar amount but I can tell you Tesla needs to communicate some fix asap. That is why I started the process of trying to file a battery claim through the local service center, as well as contacting my state's attorney general. The level of customer service and priority for early adopters should be a top priority for Tesla. I am on my second one and truthfully if they don't take care of this I will be selling my car which I dearly love. I have had 5 bmw's, Hondas, you name it I most likely drove it. It's unacceptable to pay so much for a car without getting answers this is wrong no matter the reason or mistake. I may just trade it in for a Rivian, Nio, or some other electric car for that matter I have almost lost my trust in Tesla. And we are not even touching on if you get in an accident or try and order parts, or set a service appt. Look at Audi and Jaguar they both placed recalls due to issues with batteries. Wake the hell up Elon and take care of your customers!

 

[DJRas]

Actually the value shown is available KW / a constant for the rated range.
The constant never changes.
They reduced available KW, thus the change in the range displayed.

THAT is an assumption that I can disprove with ScanMyTesla data over 2 years.

 

[DJRas]

Because if they do it for you, they have to do it for everyone. What does a battery pack cost Tesla to manufacture and install? That could get very expensive.

They only have to do it to the affected cars.
Which Tesla has stated is "a very few cars".
My estimate is 5% of early Model S so... maybe 5,000 cars worldwide.
Anybody that knows commercial business practices know that companies set aside reserves for warranty replacement.
IF this is a safety issue it should be covered under warranty.
IT is clearly NOT "normal gradual degradation" as expressed in the warranty.

So, YES, EVERY affected car should have its battery replaced under warranty.

 

[fbitz777]

I have TONS of data showing that the Rated Range displayed is the Usable Remaining kWh divided by 0.276 (NOT 295 EPA rating).
It DOES however predate May 15, 2019 release 2019.16.1.1
I have a dataset from Feb 7, 2019 that also shows the lower constant.

Something is amiss as well on my X75D and I think you "might be right"....I took a 200 mile trip today (non stop) and drove exactly at RATED (around 311wh/mi) as seen by the rated line on the energy graph AND I lost range miles as I was driving....at the end it seems I need to drive at 285wh/mi in order to get the rated range shown at the beginning of trip.

Not only did my battery lose some miles (5) after the update BUT also I am loosing miles driving at rated consumption (10)! Seems like there are two sets of variables (311 and 285wh/mi) running in parallel.

Not fun...however the trip estimator gave me a very accurate percentage for the trip (95% down to 8%)

Anyone ever tried to just drive at Rated and not seen the range decrease faster than the miles driven?

 

[Muffinman]

So, where does the supercharger speed capping fit in between X and Z? Both out TMS 85`s has lost 30-40% suc power simoultaneously. Would this indicate that the BMS has detected X or Z or is it a temporary precaution? Or would this be the result of something else?

 

[bhzmark]

Out of curiosity, under what scenario you believe you would file a battery replacement warranty for your car with Tesla?

When I believe a condition was covered under some specific term of the written warranty subject to the terms of the written warranty (or any additional warranty rights unders state law).

For Model 3's the warranty explicitly says 70% so I would take that as a bare minimum, but I would also look to about 80% for Model S and X because they should have better warranty coverage although it isn't written down explicitly.

Decreased range due to normal degradation is understood, not from a software update. Also it didn't matter what the battery degraded to, the charging speed was the same until this update.(at least on my car)

I'm agnostic as to hardware and software because the total output is always controlled by the software measuring things in the hardware so I think that is a false distinction. Some cars have a hardware condition of Z that didn't exist when the car was new, but over time, did occur. Perhaps because of the supercharging or temp when charging or just some random quantum wave collapsing the wrong way -- mechanical devices have inherent risks as part of their properly functioning design and use. That is the degradation of all sorts all overseen by the BMS overlord.

When the degradation, of whatever cause, results in more than 20%, or at least 30% (based on Model 3) loss in range or power plotted over the length of the warranty period, that is when the warranty should cover a repair or replacement.

Here are relevant selections:

If your Battery or Drive Unit requires warranty repair, Tesla will repair the unit, or replace it with a new, reconditioned or re-manufactured part at the sole discretion of Tesla. The warranty replacement may not restore the vehicle to a "like new" condition, but when replacing a Battery, Tesla will ensure that the energy capacity of the replacement Battery is at least equal to that of the original Battery before the failure occurred while taking into consideration other factors, including the age and mileage of the vehicle.
. . .
Your vehicle's Battery and Drive Unit are covered under this Battery and Drive Unit Limited Warranty for a period of:
• Model S and Model X - 8 years (with the exception of the original 60 kWh battery manufactured before 2015 that is covered for a period of 8 years or 125,000 miles/200,000 km, whichever comes first).
• Model 3 with Standard or Mid-Range Battery - 8 years or 100,000 miles (160,000 km), whichever comes first, with minimum 70% retention of Battery capacity* over the warranty period.
• Model 3 with Long Range Battery - 8 years or 120,000 miles (192,000 km), whichever comes first, with minimum 70% retention of Battery capacity* over the warranty period.
*For warranty claims specific to Battery capacity, the replacement Battery will be in a condition appropriate to the age and mileage of the vehicle sufficient to achieve or exceed the minimum Battery capacity for the remainder of the warranty period of the original Battery.

Note that the vehicle’s range estimates are an imperfect measure of Battery capacity because they are affected by additional factors separate from Battery capacity. The measurement method used to determine Battery capacity, and the decision of whether to repair, replace, or provide reconditioned or remanufactured parts, and the condition of any such replaced, reconditioned or re-manufactured parts, are at the sole discretion of Tesla.

. . .
The Battery, like all lithium-ion batteries, will experience gradual energy or power loss with time and use. Loss of Battery energy or power over time or due to or resulting from Battery usage is NOT covered under this Battery and Drive Unit Limited Warranty, except to the extent specified in this Battery and Drive Unit Limited Warranty.​

 

[MP3Mike]

For Model 3's the warranty explicitly says 70% so I would take that as a bare minimum, but I would also look to about 80% for Model S and X because they should have better warranty coverage although it isn't written down explicitly.

Why would you think the Model S&X should have a better degradation warranty than the Model 3, when the warranty specifically says it is not covered at all?

 

[DJRas]

When I believe a condition was covered under some specific term of the written warranty subject to the terms of the written warranty (or any additional warranty rights unders state law).

For Model 3's the warranty explicitly says 70% so I would take that as a bare minimum, but I would also look to about 80% for Model S and X because they should have better warranty coverage although it isn't written down explicitly.



I'm agnostic as to hardware and software because the total output is always controlled by the software measuring things in the hardware so I think that is a false distinction. Some cars have a hardware condition of Z that didn't exist when the car was new, but over time, did occur. Perhaps because of the supercharging or temp when charging or just some random quantum wave collapsing the wrong way -- mechanical devices have inherent risks as part of their properly functioning design and use. That is the degradation of all sorts all overseen by the BMS overlord.

When the degradation, of whatever cause, results in more than 20%, or at least 30% (based on Model 3) loss in range or power plotted over the length of the warranty period, that is when the warranty should cover a repair or replacement.

Here are relevant selections:

If your Battery or Drive Unit requires warranty repair, Tesla will repair the unit, or replace it with a new, reconditioned or re-manufactured part at the sole discretion of Tesla. The warranty replacement may not restore the vehicle to a "like new" condition, but when replacing a Battery, Tesla will ensure that the energy capacity of the replacement Battery is at least equal to that of the original Battery before the failure occurred while taking into consideration other factors, including the age and mileage of the vehicle.
. . .
Your vehicle's Battery and Drive Unit are covered under this Battery and Drive Unit Limited Warranty for a period of:
• Model S and Model X - 8 years (with the exception of the original 60 kWh battery manufactured before 2015 that is covered for a period of 8 years or 125,000 miles/200,000 km, whichever comes first).
• Model 3 with Standard or Mid-Range Battery - 8 years or 100,000 miles (160,000 km), whichever comes first, with minimum 70% retention of Battery capacity* over the warranty period.
• Model 3 with Long Range Battery - 8 years or 120,000 miles (192,000 km), whichever comes first, with minimum 70% retention of Battery capacity* over the warranty period.
*For warranty claims specific to Battery capacity, the replacement Battery will be in a condition appropriate to the age and mileage of the vehicle sufficient to achieve or exceed the minimum Battery capacity for the remainder of the warranty period of the original Battery.

Note that the vehicle’s range estimates are an imperfect measure of Battery capacity because they are affected by additional factors separate from Battery capacity. The measurement method used to determine Battery capacity, and the decision of whether to repair, replace, or provide reconditioned or remanufactured parts, and the condition of any such replaced, reconditioned or re-manufactured parts, are at the sole discretion of Tesla.

. . .
The Battery, like all lithium-ion batteries, will experience gradual energy or power loss with time and use. Loss of Battery energy or power over time or due to or resulting from Battery usage is NOT covered under this Battery and Drive Unit Limited Warranty, except to the extent specified in this Battery and Drive Unit Limited Warranty.​

I notice you did not highlight what I did in RED above "will experience gradual energy loss with time and use"
This is anything but gradual loss.

Yes, Tesla does take into account age and mileage.
My pack new had 78kWh usable (= 265 rated range * 295 Wh/mile)
Their service technician said the "Nominal Fleet-wide range at my mileage is 231 miles" ( 231 miles * 295 Wh/mi = 68kWh).
My pack had 68 kWh usable capacity on May 13 according to ScanMyTesla
My pack NOW has 60.4 kWh Usable Capacity
That is 12% below the fleet-wide average at my age/mileage or 23% degradation from new.
BOTH criteria fit that MY pack should be replaced.

BUT Tesla will not look at ScanMyTesla data to show the current "Usable Capacity".
They rely on the displayed "Rated Range" which they have manipulated from 295 Wh/mile to 276 Wh/mile (Imperfect measure of battery capacity).

Yes, I am not asking for a NEW 78kWh pack. A reconditioned pack with 68 kWh is fine.
This loss was not from use, but from software manipulation.

 

[Droschke]

Would I be wrong in assuming that X=li-ion plating (less dangerous condition) and Z=active dendrite formation (high risk condition for internal short)?

I was thinking the other way around, X and Z ... based on what @wk057 is saying X is worse than Z:

Basically they went looking for X and found Z instead. X is pretty bad, but doesn't seem to have happened anywhere. Detecting X is definitely a good thing. Z is not good, but not as bad as X. The process of looking for X's ended up finding a bunch of Z's as well. Z was not being looked for and wasn't known. Detecting Z is still a good thing. The people with a rapid range loss have condition Z.

I also understood that the Li-Plating leads to dendrite formation.

 

[egn1]

I found an interesting paper about detection of nascent internal shorts caused by dendrites.

Of course, a dendrite perforating the separator will not always cause a thermal runaway. If it isn't severe enough it may just cause higher self-discharge, or it is burned away by high current and just disappears.

So if the self-discharge of the cell blocks can be monitored or measured by some means, a higher value than normal may be an early indication of an catastrophic failure. Information from balancing can help to detect whether some cell blocks are always lower than others. More sophisticated methods are described in the paper above.

The nascent shorts may be the X mentioned above. Detection is very important to be able to take measures to make cells safe again.

 

[MP3Mike]

That is 12% below the fleet-wide average at my age/mileage or 23% degradation from new.
BOTH criteria fit that MY pack should be replaced.

It sounds like, from what @wk057 said, that the range reduction you are seeing is a software bug and that Tesla is working on fixing it. So they likely aren't going to even consider a warranty claim on your battery until after they have fixed the software.

 

[llavalle]

My understanding is that EPA range is determined by driving the vehicle, under test conditions, until it shuts down. This is probably where 295 Wh/mi multiplier comes from. However, I thought that zero wasn't really zero and that there was still some drivable range past zero. Is it possible Tesla displays the correct EPA range, but then decrements that range based on a lower 276 Wh/mi multiplier so that when you hit zero, you still have some drivable range as opposed to the vehicle shutting down (as in the EPA test)? Totally speculating.

The EPA number of 295 is including losses from the charger when going from AC to DC. i.e. they calculate your utility will bill you. Each car has an internal value for the rated multiplier. For example, on my 85D, this is what the car uses.

VAPI_ratedWattHourPerMile,290.000 --> i.e. 290wh/mile.

This is the value used by the car to measure the rated range. Each model is different. 75Ds have better effeciency so consume less. P85D are worst.. and so on.

Another internal value is the "nominal full pack remaining).

BMS_nominalFullPackEnergyRemaining,77.100 --> 77.1kWh usable (down from around 78 when it was new).

When charging to 100%, my car shows 265 miles (lost a bit since new.. I'm over 60K miles)... exactly 77.1kWh at 290wh/mi. It shows 239 miles at 90%... exactly 90% of 77.1 @ 290wh/mi.

The EPA rated this car as 34kWh/100 miles.. aka, 340wh/mi .

As you can see, the EPA number (in energy) is not a 100% match to what you'll see if you match the energy graph.

The "rated" miles on your dash is simply the BMS calculation of the energy remaining in kWh divided by the hardcoded wh/mile value of your model. The consumption never changes, it'll ALWAYS be 290 for my car... but as the pack degrades, the energy remaining will go down so will the rated range.

 

[Leeboy22001]

My S60 new had an EPA (Typical) range of 208 miles, with 58.6kWh usable battery works out at 285W/mile. I now have a typical range of 164 miles, with 285W/mile this gives me 46.7kWh usable battery, which is exactly what Scan My Tesla is reporting !.. this works out at 21% degradation.

 

[sorka]

I'm also hesitant to say it, since, again, I don't want to inflate this issue beyond where it already is and cause further speculation, but: If you have a car with an 85-type pack (85 or 70) then you should probably update if you either supercharge a lot, charge to 100% often, or both.

Getting ready to do a 2500 mile road trip in a few weeks. I'm down 11 miles from new at 94K miles on my P85D. If I took v9, which I really don't want to for many other reasons, and as a result, lost an additional 30 miles, there is leg of the trip that would be impossible for me to make that I can currently make with v8 unless I were to slow from 75 MPH, the speed limit on that leg, to something like 50MPH which might not be safe. It's quite possible that despite all of my regen on cold soak batteries and charging for days at a time on 1.5KW in below freezing temperatures(with range mode on) that I've hit all the checks that seem to correlate to others who've lost a large amount of range.

I'm really torn about what to do. I respect your opinion hugely and when you say we should update I have to seriously consider that despite my disdain for v9.

 

[DW254]

After several rounds back and forth with Tesla's Rocklin, CA service manager, who forwarded my emails to Tesla's "lead battery engineering team" regarding my overnight 30-mile range loss, I today received the following response:

Mr. Wells,

The lead battery engineering team has concluded their assessments of your battery and have found nothing abnormal with the battery.

Your concern regarding firmware dropping range over night is slightly misleading. Each charging cycle reviewed the car was charged to an average of 89.7% or slightly above the 90% threshold which coincides with your mentioned charging habits. When calculating the estimated range at a full 100% charge this places the threshold around 247 miles of useable range. Your battery is 4 year and 7 months old and was rated at 265 EPA estimated range when brand new. As with all vehicles this EPA estimation of range is based upon several internal and external settings. Items included in this are the steady state driving condition of 55 mph on level graded surface with no internal accessories turned on and no external forces providing resistance to the vehicle.

The vehicle battery, like all lithium-ion batteries will experience gradual energy or power loss with time and use. Loss of battery energy or power over time is the result of the use of the battery and is not covered under the battery and drive unit limited warranty, except if these conditions meet the criteria outlined in the battery and drive unit warranty.

The displayed range shows calculated range based on several factors from previous drive cycles. Pulling long term battery logs confirm our conversation where you state you primarily utilize super charging for your charging. As I explained previously if we focus more on charging the vehicle with AC charging you would notice a measurable increase in pack capacity displayed. The firmware that was downloaded provides more accurate and sophisticated set of algorithms which calculate the range available at the charge level of the battery pack.

The range estimation of 256 as you stated varies 8 miles from our calculated range of 247 as previously mentioned.
I hope you can take this provided information and have a deeper understanding of what your calculated range is representing.

Tesla stands by our vehicle warranty and our battery warranties. If there was a fault with the pack outside of standard lithium-ion wear and tear we are always more than happy to provide those services to you and all of our customers.

Respectfully,
Christopher D. Elder | Associate Service Manager, Technical Operations

My reply:

Hi Chris,
This is a completely unacceptable response.

If you check the logs and notice the times I charged to 100% in preparation for a longer driving distance, it would show 250 to 255 miles of range listed on my dashboard. After the firmware update a 100% charge listed 222 miles on my dashboard. I’m well aware of the “gradual” loss of a Tesla battery, and noticed after 4 years of driving a range loss from 265 miles on a full charge to around 255 miles. That is as expected, and I have no issue with a normal gradual loss. The 30-mile range loss after the software update was not gradual or normal. If as you report there is a 247 drive range on my car presently, how is it that the dashboard with a 50% charge reads only 111 miles? I just checked the car and it lists a 37% charge and 81 miles of range. Do the math. That equals less than 220 miles on a full charge.

Obviously, I don’t charge often to 100%, but always kept an eye on how my drive range was going by noticing how many miles of range was available when I had a 50% charge. Before the update when my battery showed a 50% charge, it would list 125-128 miles in driving range. After the update when my battery shows a 50% charge, as of today it now lists a 110 mile driving range.

The Tesla engineering team can attempt to misdirect the issue here by claiming the firmware simply “provides more accurate and sophisticated set of algorithms which calculate the range available at the charge level of the battery pack”, but the truth is my vehicle lost 30 miles of range with the software update. My driving or charging habits have not changed since the software update. Before the update I could drive from my home to Modesto and back to see my daughter without a charge. Before the update I could drive to Truckee without a charge. Now I have to charge for both of these trips.

With Tesla not willing to return the range either with a software update, battery replacement, or $10,700 upgrade paid for the higher range vehicle, I am left with no option but to seek restitution through an NCDS claim, which I will be filing tomorrow.

Thanks Chris for your time and attention on this issue over the last couple of week and for your following up with your engineering team to bring back their response.

Respectfully,
-Danny

In previous correspondence I expressed my reluctance to enter into litigation or arbitration over this issue. However, I assured them that with a $100,000 purchase price, if Tesla is not willing to provide restitution in terms of either a software correction to restore range, a battery replacement with the range I purchased, or a $10,700 refund for the additional range purchased that has been removed, I would not hesitate to enter into arbitration or participate in class action litigation. I also reported to them that at least one Tesla owner affected with the range loss has filed an NCDS claim, which has been accepted, indicating their viewing this issue as arbitration worthy.

 

[Lukez]

After several rounds back and forth with Tesla's Rocklin, CA service manager, who forwarded my emails to Tesla's "lead battery engineering team" regarding my overnight 30-mile range loss, I today received the following response:

Mr. Wells,

The lead battery engineering team has concluded their assessments of your battery and have found nothing abnormal with the battery.

Your concern regarding firmware dropping range over night is slightly misleading. Each charging cycle reviewed the car was charged to an average of 89.7% or slightly above the 90% threshold which coincides with your mentioned charging habits. When calculating the estimated range at a full 100% charge this places the threshold around 247 miles of useable range. Your battery is 4 year and 7 months old and was rated at 265 EPA estimated range when brand new. As with all vehicles this EPA estimation of range is based upon several internal and external settings. Items included in this are the steady state driving condition of 55 mph on level graded surface with no internal accessories turned on and no external forces providing resistance to the vehicle.

The vehicle battery, like all lithium-ion batteries will experience gradual energy or power loss with time and use. Loss of battery energy or power over time is the result of the use of the battery and is not covered under the battery and drive unit limited warranty, except if these conditions meet the criteria outlined in the battery and drive unit warranty.

The displayed range shows calculated range based on several factors from previous drive cycles. Pulling long term battery logs confirm our conversation where you state you primarily utilize super charging for your charging. As I explained previously if we focus more on charging the vehicle with AC charging you would notice a measurable increase in pack capacity displayed. The firmware that was downloaded provides more accurate and sophisticated set of algorithms which calculate the range available at the charge level of the battery pack.

The range estimation of 256 as you stated varies 8 miles from our calculated range of 247 as previously mentioned.
I hope you can take this provided information and have a deeper understanding of what your calculated range is representing.

Tesla stands by our vehicle warranty and our battery warranties. If there was a fault with the pack outside of standard lithium-ion wear and tear we are always more than happy to provide those services to you and all of our customers.

Respectfully,
Christopher D. Elder | Associate Service Manager, Technical Operations

My reply:

Hi Chris,
This is a completely unacceptable response.

If you check the logs and notice the times I charged to 100% in preparation for a longer driving distance, it would show 250 to 255 miles of range listed on my dashboard. After the firmware update a 100% charge listed 222 miles on my dashboard. I’m well aware of the “gradual” loss of a Tesla battery, and noticed after 4 years of driving a range loss from 265 miles on a full charge to around 255 miles. That is as expected, and I have no issue with a normal gradual loss. The 30-mile range loss after the software update was not gradual or normal. If as you report there is a 247 drive range on my car presently, how is it that the dashboard with a 50% charge reads only 111 miles? I just checked the car and it lists a 37% charge and 81 miles of range. Do the math. That equals less than 220 miles on a full charge.

Obviously, I don’t charge often to 100%, but always kept an eye on how my drive range was going by noticing how many miles of range was available when I had a 50% charge. Before the update when my battery showed a 50% charge, it would list 125-128 miles in driving range. After the update when my battery shows a 50% charge, as of today it now lists a 110 mile driving range.

The Tesla engineering team can attempt to misdirect the issue here by claiming the firmware simply “provides more accurate and sophisticated set of algorithms which calculate the range available at the charge level of the battery pack”, but the truth is my vehicle lost 30 miles of range with the software update. My driving or charging habits have not changed since the software update. Before the update I could drive from my home to Modesto and back to see my daughter without a charge. Before the update I could drive to Truckee without a charge. Now I have to charge for both of these trips.

With Tesla not willing to return the range either with a software update, battery replacement, or $10,700 upgrade paid for the higher range vehicle, I am left with no option but to seek restitution through an NCDS claim, which I will be filing tomorrow.

Thanks Chris for your time and attention on this issue over the last couple of week and for your following up with your engineering team to bring back their response.

Respectfully,
-Danny

In previous correspondence I expressed my reluctance to enter into litigation or arbitration over this issue. However, I assured them that with a $100,000 purchase price, if Tesla is not willing to provide restitution in terms of either a software correction to restore range, a battery replacement with the range I purchased, or a $10,700 refund for the additional range purchased that has been removed, I would not hesitate to enter into arbitration or participate in class action litigation. I also reported to them that at least one Tesla owner affected with the range loss has filed an NCDS claim, which has been accepted, indicating their viewing this issue as arbitration worthy.

Why do they keep saying that the displayed range is based on a number of factors including your driving habits. Maybe they don't think you are talking about rated range?
I think everyone should start saying rated range when speaking with Tesla support so that there is no confusion on which range you are talking about (actual driving distances, ideal, rated)