Wiki Sudden Loss Of Range With 2019.16.x Software

[DJRas]

Adding myself to the list of affected owners on a 85kWh pack. Went from 6% degradation to 17% right after the software update. Finally got to a service center and the tech said it's because of high supercharger usage, and it's something that Tesla implemented to protect the battery. I drive a lot and the lower range creates more of a need for me to charge more frequently, and supercharging is convenient for me as I'm commuting to/from work.

My concern (on top of the fact they did this with no communication and no plan for resolution), is that they may decide to degrade the battery again to "protect" it, and my car become essentially useless given my driving patterns, which is the entire reason I bought the car in the first place.

I also wonder how this factors into the "unlimited" battery warranty, since a battery with significantly lower range than the rest of the fleet is no longer performing as expected and should be replaced?

Exactly my situation.
I would expect that they believe your battery was closer to 12 percent degraded prior to the update and that you are closer to 23% now.
I also now MUST supercharge twice per day for my commute and trips i used to make without needing to Supercharge i now must.
That they hide the usable kWh and adjust the conversion factor at whim to further obfuscate the actual degradation is not right.
If they did this to protect from fire because they detected some anomaly in our packs then NHTSA needs to investigate.

 

[David99]

I highly doubt the amount of supercharging or how many times someone charged to 100% (or close to) has anything to do with the limitations. I have way more supercharging than any of the affected cars. 65% to 70% of my 222k miles are on superchargers. Basically 150k miles worth of supercharging. I also charge to 100% frequently. Probably 120 times in the past 5 years. We know those two things are more stressful to the battery yet that has not triggered the limited capacity on my car. I also live and drive in mostly hot areas so my battery has be subjected to less than ideal conditions for 5 years. Yet I'm (so far) not affected.There is no reason my battery would hold up better than any other 85 pack.

Since it has been speculated that Tesla might bypass some modules (that are bad). There is no wiring or switches in the battery that would allow certain cells, bricks or modules to be bypassed. All cells are charged and discharged at all times. There is no way Tesla could possibly exclude any cells or blocks or modules.

Yes, each individual cell has a fuse that will blow and disconnect the individual cell from a brick of parallel cells if it shorts out or fails. If that happens you lose 1/74th of you capacity (technically only one brick is affected but since they are in series, the weakest one limits the entire chain). But even if that happens, the charge voltage would be the same as before. We can safely rule out blown fuses and bypassed modules.

 

[Droschke]

Adding myself to the list of affected owners on a 85kWh pack. Went from 6% degradation to 17% right after the software update. Finally got to a service center and the tech said it's because of high supercharger usage, and it's something that Tesla implemented to protect the battery. I drive a lot and the lower range creates more of a need for me to charge more frequently, and supercharging is convenient for me as I'm commuting to/from work.

My concern (on top of the fact they did this with no communication and no plan for resolution), is that they may decide to degrade the battery again to "protect" it, and my car become essentially useless given my driving patterns, which is the entire reason I bought the car in the first place.

I also wonder how this factors into the "unlimited" battery warranty, since a battery with significantly lower range than the rest of the fleet is no longer performing as expected and should be replaced?

Would you post the detail about your car? You can use some of the data points from this sheet and even add yourself to it.

Also, I think you meant "unlimited" miles in 8 years.

Excellent feedback.

 

[tga]

Your first sentence is not true. Subsequent sentences are consistent with what I wrote, viz, the limit is by software, whether software out of the factory, software in ECU flash at dealer, or software from OTA update.

Everything I wrote was correct. I'm not sure you are clear on how these counters work. The rev counters are not a limit of any kind; performance, range, or otherwise. They are simply a reporting/"tattle tale" mechanism that counts the number of times the spark plugs have fired in certain high rev ranges and records the total engine hours at the last one.

But please do buy the porsche and let us know how that goes.

I have. Twice. They worked just fine. A 986 Boxster (bought new) and a 996 GT3 (used/CPO). Both have type 1 over revs from me bouncing off the rev limiter at autocrosses. The GT3 came with a small number of type 2's, but has had a few hundred hours of run time since the last one. It still runs like new.

 

[DJRas]

We are now going on 12 weeks since 2019.16.1.1 was released. There have been 5 updates that I have installed since then. None have done anything to address our problems.
They have not even said one real reason for this.
I still believe Tesla will do us right and fix it. They just need a BIG shove in the right direction.

 

[Droschke]

I highly doubt the amount of supercharging or how many times someone charged to 100% (or close to) has anything to do with the limitations. I have way more supercharging than any of the affected cars. 65% to 70% of my 222k miles are on superchargers. Basically 150k miles worth of supercharging. I also charge to 100% frequently. Probably 120 times in the past 5 years. We know those two things are more stressful to the battery yet that's not seems to trigger the car to limit the capacity. I also live and drive in mostly hot areas so my battery has be subjected to less than ideal conditions for 5 years. Yet I'm (so far) not affected.There is no reason my battery would hold up better than any other 85 pack.

Since it has been speculated that Tesla might bypass some modules (that are bad). There is no wiring or switches in the battery that would allow certain cells, bricks or modules to be bypassed. All cells are charged and discharged at all times. There is no way Tesla could possibly exclude any cells or blocks or modules.

Yes, each individual cell has a fuse that will blow and disconnect the individual cell from a brick of parallel cells if it shorts out or fails. If that happens you lose 1/74th of you capacity (technically only one brick is affected but since they are in series, the weakest one limits the entire chain). But even if that happens, the charge voltage would be the same as before. We can safely rule out blown fuses and bypassed modules.

Great observation. So, this might be either a hoax/mistake, or we really have bad packs that Tesla knows about and instead of issuing warranty replacement Tesla has chosen the cheap route to "protect" and "prolong" till the 8 years expires.

 

[DJRas]

I highly doubt the amount of supercharging or how many times someone charged to 100% (or close to) has anything to do with the limitations. I have way more supercharging than any of the affected cars. 65% to 70% of my 222k miles are on superchargers. Basically 150k miles worth of supercharging. I also charge to 100% frequently. Probably 120 times in the past 5 years. We know those two things are more stressful to the battery yet that has not triggered the limited capacity on my car. I also live and drive in mostly hot areas so my battery has be subjected to less than ideal conditions for 5 years. Yet I'm (so far) not affected.There is no reason my battery would hold up better than any other 85 pack.

Since it has been speculated that Tesla might bypass some modules (that are bad). There is no wiring or switches in the battery that would allow certain cells, bricks or modules to be bypassed. All cells are charged and discharged at all times. There is no way Tesla could possibly exclude any cells or blocks or modules.

Yes, each individual cell has a fuse that will blow and disconnect the individual cell from a brick of parallel cells if it shorts out or fails. If that happens you lose 1/74th of you capacity (technically only one brick is affected but since they are in series, the weakest one limits the entire chain). But even if that happens, the charge voltage would be the same as before. We can safely rule out blown fuses and bypassed modules.

Hmmm... all 74 cells in a brick are parallel wired together. So, if an individual cell fuse blows then only that brick has limited capacity (73 parallel batteries instead of 74). The 6 bricks are then wiired in series to make a module and 16 modules make up our 85kWh packs.

So, an individual cell failure would be 1/7104 (0.014%) reduction in capacity. It wouldn't affect brick or pack voltage. Just usable kWh.

 

[DJRas]

Very interesting since they say too much Supercharging hurts your battery (though unproven and i believe incorrect)

https://electrek.co/2019/08/03/tesl...inable-free-unlimited-supercharging-perk/amp/

 

[Lukez]

[


I am in a similar boat. In 3 years I:
Charged up to 100% less than 10 times, every year annually to check and record the range, for degradation and comparison purposes, otherwise it was for an immediate journey.
I only Supercharged about 10-15% of the time.
I normally operated between 20-80%
I never kept the car for any length of time at a high SoC. After logging the annual 100% range figures I always drove it to reduce the SoC.
But my battery has been capped by just over 15%.
So logic suggests that Tesla's actions don’t seem to be linked directly to how we have treated our batteries. I assume they must have found, or mis-diagnosed Plating, but given how carefully I have treated my battery over the 3 years, it seems unlikely. So, as today is learning day, I am open to suggestions.

I also don’t really want money, I would just like my battery back to where it was. In response to Tesla's claim that I should wait patiently as they 'are working on a solution' I did suggest if they were that confident they could give me a loaner until the solution was found, or a temporary battery until the solution was found, or compensation, each week, until the solution was found. They haven’t responded yet.

Is most of your charging AC then? Or DC via chademo?

 

[tga]

Hmmm... all 74 cells in a brick are parallel wired together. So, if an individual cell fuse blows then only that brick has limited capacity (73 parallel batteries instead of 74). The 6 bricks are then wiired in series to make a module and 16 modules make up our 85kWh packs.

So, an individual cell failure would be 1/7104 (0.014%) reduction in capacity. It wouldn't affect brick or pack voltage. Just usable kWh.

The amp hour capacity of the entire pack is limited by the amp hour capacity of the weakest group of 74 parallel cells.

Another way to look at it - take 4 12V 10 Ah batteries and wire them in 2p2s configuration and you have a 24V, 20Ah (480Wh) battery. Remove one and replace with a jumper, and you have a 24V, 10Ah battery (240Wh), made from 12V, 10Ah in series with a (virtual) 12V, 20Ah. But you can't pull more than 10Ah from the combined pack before you drain the 10Ah battery.

 

[MP3Mike]

Hmmm... all 74 cells in a brick are parallel wired together. So, if an individual cell fuse blows then only that brick has limited capacity (73 parallel batteries instead of 74). The 6 bricks are then wiired in series to make a module and 16 modules make up our 85kWh packs.

So, an individual cell failure would be 1/7104 (0.014%) reduction in capacity. It wouldn't affect brick or pack voltage. Just usable kWh.

Nope, you're forgetting that as soon as that one weak brick reaches the low voltage limit the entire pack shuts down even though the other bricks have plenty of capacity left. So your capacity is reduced by 1/74 for each cell that gets disconnected in the weakest brick.

So if you lose one cell in a single brick your pack has the same usable capacity as if it loses one cell in every brick.

And if you lose 50 cells in a single brick you have lost 68% of your usable capacity. And the problem is once you lose a few cells in a brick it put more strain on the other fusible links and so you can end up losing the whole brick.

I suspect that Tesla has the ability to estimate how many cells have gotten disconnected from each brick based on the performance of them.

 

[sorka]

I think you’re confusing EPA rating with the number displayed on the vehicle display. The EPA range was calculated using a new vehicle based on a battery of tests. The tests were done, and the range value was legit at the time of sale. No law was broken as far as the EPA is concerned. Just about every vehicle loses efficiency over time so expecting the EPA range for the life of the vehicle is a fallacy. Your issue is warranty related not EPA related regardless of what multiplier Tesla uses for the display. Hell, the multiplier in my Model 3 changed earlier this year to “give” me more range. It’s completely arbitrary and has no effect on actual range.

The reduction in range is NOT from reduction in efficiency which is exactly my point. This is exactly like reducing the size of the gas tank with a software update.

I'll remind you that I am not yet effected. I can charge to 241 miles (with range mode on) and I can get to 4.2 volts at 100%.

It's very likely that as soon as this software update is forced upon me I could lose as much as 20% of my existing current capacity. I'm on a trip that I take once a year where I have to charge to 100%. I almost never do it except for this trip. This software update would remove my ability to make this trip.

 

[tga]

It's very likely that as soon as this software update is forced upon me I could lose as much as 20% of my existing current capacity.

Why are you so adamant that you're next? We don't know what the trigger is...

 

[Evoforce]

Well, my 254 miles has been cut to 238 miles at full charge. This is especially bad for those of us that tow... We need the longer range and can't afford to have it shortened. Tesla better be upfront and explain why I have to sacrifice 14 miles. If it is a safety thing I guess i will have to swallow that bitter pill but they better expedite supercharger installations. Not happy about this and I don't like having it shoved on me without apology or explanation. End of the world? No, but it will make things more difficult and more time consuming for charging.

 

[FredTMC]

Except that even the few here in the forum who said they were not effected are now reporting in that they're losing total available kWh. Basically, if you're not yet effected, you will be eventually the first time you hit a triggering state.

Not if the new slower supercharger charging reduces the dentrite growth

 

[Evoforce]

What sucks for me more in the short term is that is this update is installed while I'm in Arizona, I'll have to get towed at least part way as AP1 Tesla's won't charge in some older superchargers with v9. A couple in a 2015 S had to get towed from Indio two days ago when we were there because of this bug.

If there are any Electrify America stations working, use those with a chademo adapter.

 

[sorka]

Not if the new slower supercharger charging reduces the dentrite growth

I've seen no evidence that a lot of supercharging is the trigger. On the contrary, I've seen convincing anecdotes from extremely high supercharging users that have had no software induced cap after this update.

 

[sorka]

Why are you so adamant that you're next? We don't know what the trigger is...

With the recent posts in the last few days from those that were previously not effected but are just now starting to be, it's clear this will eventually get everyone.

 

[dhanson865]

Its not an arbitrary number. It is the result of the EPA testing, and is from Tesla. Its also where the little line is that says rated under it on our wh/mi consumption screen when you are set to rated range.

Every once in a while someone will mention how EPA tests cars and I'll post this:

EPA doesn't test the car in any way, it's all self reported numbers provided by Tesla.

• EPA numbers are self reported and only a small number of car models each year are chosen for random testing. In 2017 that percentage was near 9.58% (0.0958 if I got the math right).
  
  
• For example in 2017 the EPA tested 0 Tesla cars. Same for 2018 as well.

See Data on Cars used for Testing Fuel Economy | US EPA for the raw data.

You'd be right to say that "EPA Ratings" are posted and there is a rated wh/mi that is correct for some sort of math for some combination of car make/model/wheels but we sure know that no one at the EPA tested all those combinations.

 

[ran349]

Every once in a while someone will mention how EPA tests cars and I'll post this:

EPA doesn't test the car in any way, it's all self reported numbers provided by Tesla.

• EPA numbers are self reported and only a small number of car models each year are chosen for random testing. In 2017 that percentage was near 9.58% (0.0958 if I got the math right).
  
  
• For example in 2017 the EPA tested 0 Tesla cars. Same for 2018 as well.

See Data on Cars used for Testing Fuel Economy | US EPA for the raw data.

You'd be right to say that "EPA Ratings" are posted and there is a rated wh/mi that is correct for some sort of math for some combination of car make/model/wheels but we sure know that no one at the EPA tested all those combinations.

To me EPA testing doesn't necessarily mean that the EPA did the test, but that the test was done using EPA test procedures. Otherwise, they should never call the numbers EPA values.