Wiki Sudden Loss Of Range With 2019.16.x Software

[kavyboy]

If they're messing around with EPA ratings to give falsified watt hours / mile calculations they can hide any amount of degradation they want. They can reduce your capacity to 10% "for longevity" so you only get 20 real miles, but change the watt hours so your car shows more rated miles range than it ever had when new. It's dishonest and potentially illegal if the EPA investigates, but they might be subtlely doing it according to the last few posts. I'll check my driving and see what it shows.

Surely they wouldn't do this after the dieselgate scandal, would they? That would be insane.

 

[malventano]

I know folks haven't dug into this as much as the range issue, but the lower maximum charge voltage should lead to max charge amps falling off at a lower SOC as well as a longer charge time overall since the Vmax is a lower value, and charge current is (roughly) proportional to the difference between the voltage applied and the steady state (0 amps) cell voltage at a given SOC. So for the same reason that folks see regen being limited at lower SOC than expected, supercharges will also be more limited and will take even longer to get to a (now) lower kWh into the pack at a given stop.

 

[ran349]

UPDATE:
I just finished having my battery tested at Oceanside Service Center.
As expected they said that my battery does not fit the criteria for replacement.
The test is HV Battery Capacity (looking at Charge Amperage Capacity?).
My battery is version 41 (41 is the number they used... but they didn't call it version).
Original rated range for this pack was 264 miles at 295Wh/mi (77.88 kWh usable capacity).
A battery with my age/mileage should have a capacity of 231 miles (Fleet-wide average).
IF my battery is <90% of that window they can replace my battery under warranty.
With my 217 mile rated range that is 93.9% therefore... no warranty replacement.
BUT, the currently reported 217 mile rated range is NOW based on 276 Wh/mi (Which they saw while looking at my recent drives).
IF we use the 295 Wh/mi calculation for rated range my current max range is 204 miles - 88.3% of nominal.
ALSO, with rev 2019.20.2.1 the most I can charge to is 97% or 210 miles (@276 Wh/mi) thus 90.9% of nominal.
At 295 Wh/mi my 97% range is only 196 miles or 85% of nominal.

I will be returning this afternoon to discuss this information with the technician

Additionally, The official Tesla stance is "These changes are meant to increase battery longevity. NOT related to the fires".
When confronted with my stance that they are software degrading MY battery to keep it from degrading on its own...
They said "yeah... that seems wrong" and "Tesla will likely look closed at the new data they gather after this update and will "likely" revise the algorithm and POSSIBLY restore some of our range to those of us affected

Also, my battery reported a BMS error "Battery_Brick_Limited (hidden)". They did not explain that well. Just that it was "not critical to battery usage" and "NOT covered under warranty"

The Service Manager and the Technician really seemed to care about my concerns and they WANT to replace my battery. But until they can go to engineering with an "Out of normal condition" their hands are tied.

They also did verify that I COULD buy a replacement battery (for about $20,000 installed).

Oh Yeah!!! while I was there they replaced my recalled air bag!

I don't think Tesla changed the calculation for rated miles in your car based on your last reported Scan My Tesla data.
Your nominal full pack which is used to calculate rated range showed 64.3 kWh. Your full rated range was given as 218 miles. By using the .295 multiplier you get 218 x .295 = 64.31 kWh, which exactly matches the nominal full pack number.
Using rated miles, your 217 miles would be a degradation of about 17.8%. But if you can only charge to 97%, you could argue that your true degradation is about 20%. Based on what they told you, you would be entitled to a replacement battery at around 208 miles range, which is about 21% degradation from the original 264 miles. That's a lot better than the 30% degradation number people often mention for the required replacement point. Are you sure that's what they meant? If so, you are already pretty close, and you will probably soon qualify for another battery.

 

[Lukez]

The batteries do settle but the voltage after several minutes is what you check, not what it is when you're actually charging it.

You probably have a very small amount of artificial range reduction. What was the diff between min and max if your avarage for 4.16?

Went back and looked at the logs for the charging session.
I topped out at 99.4% with the data below.
Anyone understand the difference between all the AC and DC charge columns? Shouldn't the AC total and DC total add up to Charge Total?
Data below:

 

[DJRas]

I'm sorry to ask a dumb question - I have a '13 P85 that I'd like to check for this - is the only way to do so to max charge the battery?

No, you can get the 100% number by looking at your "Rated" miles at whatever state of charge.
as example... my 90% charge rated miles is 197. 197/0.9 = 217.
my old 90% was 223... 223/0.9=247

The Wh/mi is a bit trickier because they NEVER show your actual kWh state of your battery (without a CANBUS reader.

But, if you look at an individual trip you can see how many miles you drive and the Wh required as well as the "Rated miles" used (starting rated miles minus the ending Rated miles). Divide tthe same actual Wh used by the aRated miles used and THAT gives you their calculate Wh/mi Rated.

 

[Lukez]

Went back and looked at the logs for the charging session.
I topped out at 99.4% with the data below.
Anyone understand the difference between all the AC and DC charge columns? Shouldn't the AC total and DC total add up to Charge Total?
Data below:
View attachment 425753

Added Miles for easier reference. Also something to note is 243 full rated = 71.8kwh which is correct on my car.

 

[DJRas]

I don't think Tesla changed the calculation for rated miles in your car based on your last reported Scan My Tesla data.
Your nominal full pack which is used to calculate rated range showed 64.3 kWh. Your full rated range was given as 218 miles. By using the .295 multiplier you get 218 x .295 = 64.31 kWh, which exactly matches the nominal full pack number.
Using rated miles, your 217 miles would be a degradation of about 17.8%. But if you can only charge to 97%, you could argue that your true degradation is about 20%. Based on what they told you, you would be entitled to a replacement battery at around 208 miles range, which is about 21% degradation from the original 264 miles. That's a lot better than the 30% degradation number people often mention for the required replacement point. Are you sure that's what they meant? If so, you are already pretty close, and you will probably soon qualify for another battery.

Yes, I am SURE that is what they meant... however the target value slides with miles and age... so it is a bit of a moving target (analyzed by fleet-wide data).

They said... with my now being REQUIRED to SuC twice per day for my commute that I would likely qualify soon.
Also hinted that "stressing the battery" might accelerate that too.
So... Jack-Rabbit starts and charging to 97% seem to be in my future.

 

[DJRas]

Went back and looked at the logs for the charging session.
I topped out at 99.4% with the data below.
Anyone understand the difference between all the AC and DC charge columns? Shouldn't the AC total and DC total add up to Charge Total?
Data below:
View attachment 425753

No, there is also Regen charge and parasitic losses (preconditioning AC use, etc).

 

[DJRas]

I don't have access to that. Would it be accurate if I got my car down to 0% (until it shuts down) and then charge to 100% and see how much energy is added? Not sure how accurate that would be, but I'm for sure willing to try it if it could get the info needed.

No, that wouldn't be completely accurate because of battery heating (or cooling) required as well as Air Conditioning use if you are sitting there.

 

[DJRas]

FYI, fleet wide average is 92% @ 135K miles. Your degradation is 22.57%.

My degradation is 6.1% @93 K miles which as you can puts me exactly on the red line....but then I'm still on v8.

My Data is highlighted (But, this is only 1,400 cars... not the 200,000 Model S data they have

 

[sorka]

I don't think Tesla changed the calculation for rated miles in your car based on your last reported Scan My Tesla data.
Your nominal full pack which is used to calculate rated range showed 64.3 kWh. Your full rated range was given as 218 miles. By using the .295 multiplier you get 218 x .295 = 64.31 kWh, which exactly matches the nominal full pack number.
Using rated miles, your 217 miles would be a degradation of about 17.8%. But if you can only charge to 97%, you could argue that your true degradation is about 20%. Based on what they told you, you would be entitled to a replacement battery at around 208 miles range, which is about 21% degradation from the original 264 miles. That's a lot better than the 30% degradation number people often mention for the required replacement point. Are you sure that's what they meant? If so, you are already pretty close, and you will probably soon qualify for another battery.

The is not correct. The reserve has never been included in the usable capacity and the useable capacity is the only non constant number used to calculate rated range.

For example, I just scanned this off another co-workers car 20 minutes ago:

His full 100% charge shows 239 rated currently with his useable capacity at 70.6 kWh. This is exactly 295 wh / mile. In this case, this car has not been effected in any way by the update.

 

[sorka]

My Data is highlighted (But, this is only 1,400 cars... not the 200,000 Model S data they have

More than large enough sample size.

 

[MaryAnning3]

I love to get an idea of what cars tend to be most effected by this issue. Are these mostly model S from 2012 to 2015?
Are the equally 60 kwh and 85 kwh? (or maybe more 60 kwh?) Are these all batteries with pure carbon anodes?

 

[Droschke]

Naive question: On a trip where the range between two superchargers works out to 75%:
is it better to charge at the first supercharger to 95% and arrive at the next one with 20%,
or to charge at the first one to 90% and arrive at the next one with 15%?
(Please feel free to include considerations associated with ambient temperature in your response.)

I don't believe doing it either way will result in sudden loss of range which is the topic of this thread.

 

[sorka]

Naive question: On a trip where the range between two superchargers works out to 75%:
is it better to charge at the first supercharger to 95% and arrive at the next one with 20%,
or to charge at the first one to 90% and arrive at the next one with 15%?
(Please feel free to include considerations associated with ambient temperature in your response.)

I realized I never answered the ambient temperature part of your question. In really cold weather I run a much larger buffer both from the standpoint of battery health and also because the range usually takes more of a hit in cold weather (denser air...maybe wet roads...etc) than the trip planner accounts for. Basically my 7% target is if it's warm and there aren't any headwinds.

 

[MaryAnning3]

I don't believe doing it either way will result in sudden loss of range which is the topic of this thread.

Yes, but I think there are 5 years of charging habits that ultimately lead that "sudden loss". I think that the sudden loss is essentially a diagnoses of and treatment for a problem that developed gradually over time.

 

[MaryAnning3]

"Naive question: On a trip where the range between two superchargers works out to 75%:
is it better to charge at the first supercharger to 95% and arrive at the next one with 20%,
or to charge at the first one to 90% and arrive at the next one with 15%?"

Secret option C...charge to 85% and arrive with 10% would be even better.

I see. So the high end is more problematic than the low end!
Does everyone agree with that?

I think am going to start using an 80% to 10% protocol for supercharging while traveling rather that the 90% to 20% I have been using.

 

[ran349]

The is not correct. The reserve has never been included in the usable capacity and the useable capacity is the only non constant number used to calculate rated range.

For example, I just scanned this off another co-workers car 20 minutes ago:

His full 100% charge shows 239 rated currently with his useable capacity at 70.6 kWh. This is exactly 295 wh / mile. In this case, this car has not been effected in any way by the update.

The pack value in TM-Spy is the same as the nominal full pack value in Scan My Tesla. So @DJRas TM-Spy data would show this same thing, i.e., his rated miles x .295 would equal his TM-Spy pack voltage. And there is no question that his car has been affected.

 

[apacheguy]

Would be nice if Tesla issued a statement on this to help clear things up.

Also, my worry is that my 3, while not currently affected, will be affected in the future after enough charge cycles. Tesla’s generally do much better than other EVs in terms of degradation, but if Tesla is forcibly removing >10% capacity after a certain amount of time then this will definitely not be true.

 

[yobigd20]

I’m still on 2019.16.2 and refusing updates because I don’t want to lose range, especially since my range already sucks at 187k miles I can barely get 165 real world miles on a 100% charge. Can anyone suggest a canbus reader I can get off of amazon and point me to a cheat sheet on how to use it and what to look for? I want to be able to provide data here especially given that I’m one of the higher mileage early build cars.