Wiki Sudden Loss Of Range With 2019.16.x Software

[sorka]

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.

I'm just saying that prior this update it has never changed. Mine for instance has been 310 wh / mile on my P85D since new.

The post I was responding to made it sound like this is normal thing that Tesla has tweaked over the years which is not only false, but if they've actually changed it to partially hide the software induced cap, then it's almost certainly a felony.

I'm still not convinced given that even your own numbers add up to 295 if you include the full capacity the BMS reports on TM-SPY which matches what mine currently does on v8.

 

[DJRas]

I'm just saying that prior this update it has never changed. Mine for instance has been 310 wh / mile on my P85D since new.

The post I was responding to made it sound like this is normal thing that Tesla has tweaked over the years which is not only false, but if they've actually changed it to partially hide the software induced cap, then it's almost certainly a felony.

I'm still not convinced given that even your own numbers add up to 295 if you include the full capacity the BMS reports on TM-SPY which matches what mine currently does on v8.

The ONLY constant that works for all SoC is the Usable Remaining Divided by Rated Range and Usable Full Pack by Full Rated Range.

Do you have ScanMyTesla data?

 

[lightningltd]

Interesting read: Parked Teslas Keep Catching on Fire Randomly, And There's No Recall In Sight

Not sure if it has anything to do with our issues. If it DOES, I would say they need to do a recall on all the affected batteries.

 

[KArnold]

Threads like this are very concerning. My '17 MS100D is not affected (yet) but I'm going to be extremely hesitant to install future updates - at least until most of y'all do first. It's kind of ironic - I used to really look forward to the latest, greatest OTA updates. Now I'm afraid of them.

 

[gmo43]

Yes. I think if we stick to kWh capacity it is a cleaner discussion. Anytime "miles" or "percentage" come up as a measurement metric, it is subject to additional formulas and calculations. I bought a car with 77 kWh and now have a battery with 60 kWh. It was about 73 kWh before 2019.16.2. Plain and simple.

Well not all of know how much actual Kwh or knew as much now about BMS, all I knew it was advertised as 85kWh battery. I know ill have to buy scanmy tesla to figure what its capacity is now. I have lost about 30+ miles and have noticed me having to charge more often and longer now a days. Wish there was an was an easier way to find out back when I first bought it or even knew about such info I do now.

 

[mjmiron]

Well not all of know how much actual Kwh or knew as much now about BMS, all I knew it was advertised as 85kWh battery. I know ill have to buy scanmy tesla to figure what its capacity is now. I have lost about 30+ miles and have noticed me having to charge more often and longer now a days. Wish there was an was an easier way to find out back when I first bought it or even knew about such info I do now.

Unfortunately welcome to the club all of us are upset over this it’s like they stole something from us without asking.

Hey owner thanks for being our Ginny pig sorry we messed up but in order to fix this we are gonna reduce the capacity of your battery pack thanks for the extra 10g’s you spent. Oh and BTW once you get sick of AP buy a new one with FSD so we can test you with how that goes too.

 

[Moorebid]

Well not all of know how much actual Kwh or knew as much now about BMS, all I knew it was advertised as 85kWh battery. I know ill have to buy scanmy tesla to figure what its capacity is now.

It's pretty easy to get a ballpark figure just by taking the numbers the car gives you and doing a little math; I know of a couple ways…

1. On the Energy graph, take the displayed available range, divide that by the remaining percentage of SoC then multiply that by 100 (or use the least-common denominator), and then multiply that by the displayed average Wh/mi. For example, 111 miles range / 50% SoC * 100 * 300 Wh/mi = 66,600 Wh, or 66.6 kWh (Hey! What a coincidence, that was my last calculated value! ).
2. Note the SoC at the time the car is plugged in, then while charging divide the displayed amount of additional kWh by the difference in decimal value between the current SoC and the starting SoC. For example, 33 kWh / (.75 current SoC - .25 starting SoC) = 66 kWh; it's not as precise, but again — we're just talking ballpark here, there's margin of error in both calculations.

There may be other sources of information the car displays, but I've not gone looking; I generally do these calculations while the car is charging, so I can see exactly when the percentage meter ticks up and take the other values displayed at that time — as a sort-of worst-case-scenario (realistically, it's probably ticking up the percentage point while it's still a half-step low, but I don't care — I want my estimates for how much range I have remaining to be as forgiving as possible).

 

[CuriousG]

I know this applied to a Model 3 but does anyone want to give this a try for a Model S?

Battery Degradation "fix"? : teslamotors

Sounds similarly to what @wk057 did to reset another person's battery.

 

[egn1]

Any normally degraded lithium ion cell can be safely charged to 4.2 volts regardless of how much capacity has been lost. It may require charging slower to get there as IR increases but you can always still get there....unless the battery has attained a condition that would make it dangerous to charge that high.

Yes, you can charge lithium cells always to 4.2 V, but this doesn't mean that this is without risk. You normally don't see if it is still save to do so. Tesla now uses an algorithm to detect abnormal state in individual packs and stops charging at lower voltage. The voltage is different for every vehicle, dependent on the state.

None of the 30+ hobby chargers, some of them very smart, prevent you from charging to full capacity on any cell.

That doesn't mean that there isn't a problem with charging to 4,2 V. There are a lot of reports of exploding lithium batteries outside the EV world.

Tesla is trying to prevent battery fires by detecting lithium plating and prevent it in short-term by limiting the charge voltage, in long-term by limiting charge power according to current battery temperature, and elevating battery temperature before charging.

 

[egn1]

Any idea what kind of effect really slow charging at these temps will have on li plating? Also, nearly all of that was with range mode on which I know does not as aggressively manage the battery temp in extreme conditions. Starting at 50K miles I turned off range mode pretty much forever.

One know fact regarding charging lithium batteries is that they must not be charged below 32 F. But this isn't a physical constant, more a rule of thumb.

In reality it is a combination of temperature and charge rate that has to be adhered to prevent lithium plating. The charger rate has to be limited to the point where all lithium ions can be intercalated into the graphite anode at this rate.

The dissertation of Peter Keil has shown that in the long-term even charging at 50 F will cause much more degradation than charging at normal temperature.

So trickle charging at cold temperature isn't the best thing to do, because up to now battery heating by the BMS wasn't that aggressive, and trickle charging doesn't generate enough heat to warm the battery.

This is also the reason why in winter (night temperature going below 50 F at night) I always charge when I come home in evening with a warm battery, preheat the car in the morning before leaving, and turn Range Mode Off.

We sometimes get below 0 F for weeks in winter and the car is parked outside. When doing no preheating I get the snow flake and the blue capacity reduction shown, because the battery is "frozen".

 

[sorka]

One know fact regarding charging lithium batteries is that they must not be charged below 32 F. But this isn't a physical constant, more a rule of thumb.

In reality it is a combination of temperature and charge rate that has to be adhered to prevent lithium plating. The charger rate has to be limited to the point where all lithium ions can be intercalated into the graphite anode at this rate.

The dissertation of Peter Keil has shown that in the long-term even charging at 50 F will cause much more degradation than charging at normal temperature.

So trickle charging at cold temperature isn't the best thing to do, because up to now battery heating by the BMS wasn't that aggressive, and trickle charging doesn't generate enough heat to warm the battery.

This is also the reason why in winter (night temperature going below 50 F at night) I always charge when I come home in evening with a warm battery, preheat the car in the morning before leaving, and turn Range Mode Off.

We sometimes get below 0 F for weeks in winter and the car is parked outside. When doing no preheating I get the snow flake and the blue capacity reduction shown, because the battery is "frozen".

And I've done just the opposite. Charge the battery in the morning when it's cold so that I can leave just as it's at 90% so that at that too long and charging in the morning preheats the battery as it charges.

So basically I've done everything wrong when it comes to lithium plating. Charge really slow for a long time for many days when the battery is freezing, regen charge on cold soaked battery, and start charging in the morning to heat the battery rather than charge at night when I first get home. Currently, with v8, I have 11 miles of range loss at nearly 100K miles. I'd expect V9 to make mine one of the highest loss examples.

 

[egn1]

Threads like this are very concerning. My '17 MS100D is not affected (yet) but I'm going to be extremely hesitant to install future updates - at least until most of y'all do first. It's kind of ironic - I used to really look forward to the latest, greatest OTA updates. Now I'm afraid of them.

IMHO. if you are concerned on safety you should install the updates. The new algorithms limiting the charge voltage certainly reduces the risk of battery fires.

Off course, it comes with the negative side effect of loosing battery capacity. We have to see how that can be compensated by Tesla.

 

[egn1]

So basically I've done everything wrong when it comes to lithium plating. Charge really slow for a long time for many days when the battery is freezing, regen charge on cold soaked battery, and start charging in the morning to heat the battery rather than charge at night when I first get home. Currently, with v8, I have 11 miles of range loss at nearly 100K miles. I'd expect V9 to make mine one of the highest loss examples.

It is not your fault!

Probably it is Teslas fault, because they didn't give good advise. They always said that the BMS will handle all this, and a lot of Tesla Fans jumped in and spread this word.

But Tesla may not have known this up to 2 years ago, because this issue developed over time and probably became statistically evident at this time. Since then they started to improve temperature management and limiting charging at cold battery more and more. And now we are at a point that a few batteries catch fire by them self, and there is no protection when this happens, because it is started by an internal short.

I think this emergency action of Tesla is right at this point. May be it is a bit overdone in the moment, but charging the affected batteries to a lower voltage and reducing charge power on cold batteries certainly reduces the chance of lithium plating immediately. The internal short only happens when the dendrites grow further and puncture the separator.

I am sure that Tesla is working on further optimizing the algorithm, and this may bring back part of the capacity to some of the batteries. How the others are handled depends on the pressure the community creates, and how this can be communicated to the press and consumer right organizations.

 

[Droschke]

Tesla is trying to prevent battery fires by detecting lithium plating and prevent it in short-term by limiting the charge voltage, in long-term by limiting charge power according to current battery temperature, and elevating battery temperature before charging.

Regarding the "Tesla is trying to" part of your post, is that your educated guess or you have a link you can share with us as to the source of your statement?

 

[Droschke]

So basically I've done everything wrong when it comes to lithium plating.

Then that v9 bad baby can't wait to meet your battery ...

 

[Droschke]

sorka said: ↑
So basically I've done everything wrong when it comes to lithium plating. Charge really slow for a long time for many days when the battery is freezing, regen charge on cold soaked battery, and start charging in the morning to heat the battery rather than charge at night when I first get home. Currently, with v8, I have 11 miles of range loss at nearly 100K miles. I'd expect V9 to make mine one of the highest loss examples.

It is not your fault!

Probably it is Teslas fault, because they didn't give good advise. They always said that the BMS will handle all this, and a lot of Tesla Fans jumped in and spread this word.

But Tesla may not have known this up to 2 years ago, because this issue developed over time and probably became statistically evident at this time. Since then they started to improve temperature management and limiting charging at cold battery more and more. And now we are at a point that a few batteries catch fire by them self, and there is no protection when this happens, because it is started by an internal short.

I think this emergency action of Tesla is right at this point. May be it is a bit overdone in the moment, but charging the affected batteries to a lower voltage and reducing charge power on cold batteries certainly reduces the chance of lithium plating immediately. The internal short only happens when the dendrites grow further and puncture the separator.

I am sure that Tesla is working on further optimizing the algorithm, and this may bring back part of the capacity to some of the batteries. How the others are handled depends on the pressure the community creates, and how this can be communicated to the press and consumer right organizations.

You mentioned "But Tesla may not have known this up to 2 years ago". Don't you think Tesla should have acted earlier than 2 years and communicated with the owners about it?

 

[dark cloud]

I know this applied to a Model 3 but does anyone want to give this a try for a Model S?

Battery Degradation "fix"? : teslamotors

Sounds similarly to what @wk057 did to reset another person's battery.

I had no idea this model 3 owners with their more modern 2170 based-batteries were going through these issues also. Somehow this makes me feel better!

And I've done just the opposite. Charge the battery in the morning when it's cold so that I can leave just as it's at 90% so that at that too long and charging in the morning preheats the battery as it charges.

So basically I've done everything wrong when it comes to lithium plating. Charge really slow for a long time for many days when the battery is freezing, regen charge on cold soaked battery, and start charging in the morning to heat the battery rather than charge at night when I first get home. Currently, with v8, I have 11 miles of range loss at nearly 100K miles. I'd expect V9 to make mine one of the highest loss examples.

So now what does someone do when they get home in the winter with 60% SOC and they need to go on a road trip the next day?

You want to charge when you get home, but don't want to the car to sit at 100% for 8 hours. Yet you don't want the car to cool down first and then charge.

So the best scenario maybe is start charging right away but at a slower rate which achieves 100% just before you need to leave?

Previously the answer was always it doesn't matter; Tesla BMS handles it all. Well perhaps that isn't necessarily the case anymore.

 

[apacheguy]

Has anyone that had a range drop received a newer firmware update? I never got any range drop, skipped 16.2 (16.1 - 16.3) and just got 24.1.5 last night. Charging speed, range, almost everything has been pretty much the same for 40k miles besides maybe regen sensitivity in cold temperature (& maybe charging in cold?)

Keep in mind that it takes a couple of charge cycles for the degradation to appear. Would also be interested in seeing a supercharge taper curve for your vehicle on 2019.24.

 

[DJRas]

From the post listing all the Tesla fires (8 total outside of accidents) only 2 were while charging and they were both at Superchargers. So, if the battery damage has already happened then changing the charging tactic now on batteries that are showing some level of damage may do ZERO to stop more fires.
IF these changes are to prevent fires (and Tesla has only said that once and now says these changes are NOT related to the fires) then this IS a safety issue that NTSB should be involvedl in with outside scrutiny as to the effectiveness of any fix.
If a battery is damaged by charging using TESLA approved methods from home wall chargers to Supercharging every day and the TESLA BMS did not prevent damage to the batteries then this should be covered under warranty or recall.

 

[Gixx1300R]

From the post listing all the Tesla fires (8 total outside of accidents) only 2 were while charging and they were both at Superchargers. So, if the battery damage has already happened then changing the charging tactic now on batteries that are showing some level of damage may do ZERO to stop more fires.
IF these changes are to prevent fires (and Tesla has only said that once and now says these changes are NOT related to the fires) then this IS a safety issue that NTSB should be involvedl in with outside scrutiny as to the effectiveness of any fix.
If a battery is damaged by charging using TESLA approved methods from home wall chargers to Supercharging every day and the TESLA BMS did not prevent damage to the batteries then this should be covered under warranty or recall.

This is what I have been saying all along.