If you fast charge, Tesla will permanently throttle charging

[AnxietyRanger]

To summarize the recent data points we have on DC charging causing throttling/degradation:

1) A scanned service report from Tesla via @Naonak (plus original report of course) (in U.S.)
2) We also have @jbcarioca calling a Tesla service center where the tech recalled DC degradation issues with "H" packs (in U.S.)
3) @ODE90D having heard "unofficially" from several Tesla employees about this (in Italy)
4) We have a recollection that famed Tesla user @Bjorn possibly had noticed this throttling on his car (in Norway)

@MP3Mike kindly collected the affected @Naonak's specs in one post:

I'm pretty sure he has given most of that information in the thread:

2015 P90DL
~1 year old
~30k miles
~250 CHAdeMO charges
~55 Supercharges
Next to zero AC charges

We also have this counter-example from @thefortunes, a non-affected heavy DC user:

I mentioned my brother a "few" posts back (who knew this thread would get this long?).

He has >130k miles on his S and estimates that he has SuC 95% of those miles (typically twice a day on his 300 mile commute). Charged yesterday at 112kW.

Did I miss anything?

Maybe time for @FredLambert and Electrek.co to investigate...

 

[David99]

Just another data point.

I have 116k miles on my car. Supercharged almost 600 times, aprox 60% of my miles are driven on Superchargers, a little over 3 years old. Aprox 570 cycles on the battery. The battery degradation is about 7%. While I do see randomly reduced charge rates, it is definitely not happening all the time.
When I start charging at a Supercharger I always starts at around 112-118 kW. Compared to when it was new I think it starts to taper a little earlier and overall the charge rate is maybe a little lower. I think at 50% battery level it's about 10kW lower than it was.

According to the large battery survey, the people that use Superchargers the most have lower than average degradation. At least based on that data there is no evidence that Supercharging is very harmful.

 

[AnxietyRanger]

Looking at the people we know or suspect are affected, @Naonak, @Bjorn, @ODE90D, all seem to have the 90 kWh battery. Or am I mistaken? (Did @Bjorn get a 100 kWh upgrade?)

I wonder what battery is @jbcarioca's service center call "H pack" referring to?

 

[thegruf]

Questions:

Is this for real, the OP certainly has information from Tesla that it is, but has HQ confirmed it

Is the reduction just limiting the max charge current (ie before the taper kicks in)
or the max charge current at any state of charge including the taper (ie at all states of charge)

In which version of firmware was this strategy introduced?

Is the reduction of the charge rate a one-off drop after a certain number of charges, in which case is this the only drop
or
Is does it follow a curve according to number of charges, in which case what does this curve look like?
and
how severe can the reduction in charge rate become

Is this charge rate reduction significantly battery version related

Could Tesla offfer a charge control in the car
max charge (don't tell mommy)
safe charge (teachers favorite)

Are Tesla going to have to increase the number of SuC still further to mitigate slower charge rates (!)

Do I buy the lower mileage or higher mileage CPO when one of them may have been DC fast charged all it's life all but I dont know which

 

[Candleflame]

This thread really just results in confusion.

So much conjecture based on nothing. And SO much "I don't know a lick about physics, but I'm going to come up with some belief system to explain the information I don't have".

After (unfortunately) reading through these 19 pages of posts, I've come to these conclusions:

1) We don't know anything.
2) Nope, that's it. There's just not enough information to make any conclusion at all.

My *guess* is that the OP is just complaining because it seems the car is charging slower than he figures it should and he doesn't understand the variables involved. That complaint was met by a "tech" that really had no idea and/or was unwilling to be confrontational so they just communicated to the "Tesla engineers" and attempted (poorly) to communicate the response.

Given all the [mis]information presented here combined with my knowledge of electronics, I'd say NOTHING is being "counted" and throttled. When you see lower charging rates, there are MANY reasons for this. The OP just doesn't like what he sees and doesn't understand/accept the "too many variables" answer.

So if you see my post and haven't yet bothered to read through the 19 pages... seriously, don't waste your time. Nothing to see here.

exept that an engineer actually confirmed the throtteling.

 

[NerdUno]

@AnxietyRanger Thanks for rounding up the majority of the Tesla Cheerleaders in a single post. Funny that those same names appear in every thread that's even remotely critical of Tesla. They never let facts stand in the way of a good personal jab.

 

[182RG]

@AnxietyRanger Thanks for rounding up the majority of the Tesla Cheerleaders in a single post. Funny that those same names appear in every thread that's even remotely critical of Tesla. They never let facts stand in the way of a good personal jab.

It's fascinating psychology, isn't it? People so passionate over their expensive purchase, that they engage in a cult-like brand defense. Cognitive Dissonance 101.

I saw this with Cirrus aircraft owners. Dropping 1/2 a $Mil on an airplane generated the same effect. There was always a dedicated group that showed up on numerous forums to defend the brand, re-spin facts, and manage the message. The owners group (COPA) was very active in this. A crash, a fire, a ballistic parachute pull would guarantee an appearance. Like Scientologists.....

 

[Electric1]

Yes, at some point degradation can be determined to be unusual and evidence of a defective battery
...

"How many years will the battery last?
Based on testing, Tesla expects the battery to retain approximately 70% of its initial capacity after seven years or 100,000 miles (160,000 km)."
Model S | Frequently Asked Questions | Tesla Motors

By this defination, I guess I am out of spec because at (only) 4 years and 115k, my battery is "only" degraded b 5% or so, therefore I have an out of spec car. Maybe I should ask them to pull some cells to get me back into spec. (LOL)

 

[Matias]

You are missing the fact that this has not been confirmed.

There are numerous examples in this thread (my brother's P85, for example) with much higher SuC use and no throttling.

There are also numerous examples on this forum of one employee (or Service Center) stating something that turned out to be incorrect.

If this is false information stated by one employee, one would think, that Tesla would rectify this error. Tesla surely is aware of this thread.

 

[boaterva]

Wow.... after 20 pages, a couple of things stick out. How does this (more or less, don't use SpC too much, for some value of 'too') play with the new SpC policy that they recognize that many 3 owners will have NO option but to use SpC's for EVERY CHARGE.

If there's really no difference between SpC and Chademo (which I think I've seen, but it's been confusing...), then how does this discovery (if that is what it is) square with some percentage of future cars being charged only by SpC at the *blessing* of Tesla?

WTF is my only answer... they take charge speed degradation as a matter of course? The 2170 batteries don't do this, are that much better? This is limited to 90s? Not sure what to think....

 

[SageBrush]

If this is false information stated by one employee, one would think, that Tesla would rectify this error. Tesla surely is aware of this thread.

Hah!

TMC is a beehive of misinformation, speculation and spin. Tesla would have to be nuts to set foot in here.

 

[Matias]

Lol. I just reread the Tesla Service Invoice:

"According to Tesla engineers once vehicle has been DC fast charged over a specified amount, the battery management system restricts DC charging to prevent degradation of the battery pack."
​

This could easily be interpreted as a poorly worded attempt to explain the SuC taper.

Again, all I am saying is I would not jump to conclusions until we have facts. Nowhere does the invoice talk about a counter, no one has seen this "counter" that some are stating as fact.

@NerdUno, I can understand since you haven't been here very long, but those of us who have can easily recall many examples where something was misinterpreted (or an employee or Service Center was just flat out wrong).

Please read the whole text

"Concern: Customer states: speed of charging at Superchargers is topping out at lower
speeds then previously observed. This has happened at multiple superchargers recently.
Pay Type: Goodwill
Corrections: Supercharger General Diagnosis Conclusion: No Trouble Found
Review vehicle logs and verify charging is topping out a lower rate than observed on
earlier DC charging sessions. According Tesla engineers once vehicle has been DC fast
charged over a specified amount, the battery management system restricts DC charging to
prevent degradation of the battery pack. According Tesla engineers, this vehicle has seen
significant DC fast charging and is now has permanently restricted DC charging speeds.
Important to note, supercharging will always still be available to the vehicle and the battery
pack has not yet experienced significant degradation due to the amount of DC fast
charging performed on the pack up until this point in time. Vehicle is operating as
designed."

It is clear, that they are not talking about normal tapering.

 

[boaterva]

Hah!

TMC is a beehive of misinformation, speculation and spin. Tesla would have to be nuts to set foot in here.

Well, Jon did just the other day, on a service center mishap thread. This, of course, is a bit more dicey!

 

[SageBrush]

Thanks for rounding up the majority of the Tesla Cheerleaders in a single post.

Hmmm. Sounds like it is time for me to shave my legs and work on my belly.

In the meantime I'm happy to support Tesla and to kick the spoiled, whiny pukes to the curb.

 

[bonnie]

At the risk of being dismissed as just another cheerleader (but kind of hoping that includes cute outfits and pompoms), my two cents:

The OP likely has noticed a real issue with his battery, exacerbated by his unusual usage. My assumption is that Tesla Service correctly called that out on the repair order - but didn't give context as to how often this could happen, leaving this forum rife with speculation.

If it is widespread and going to happen to all, then yes, I agree with posters who feel this should have been disclosed - though I think it's more likely that an engineer, after the fact, discovered the problem through examining logs supplied by a service center & just replied to the service center as to what they believed. I don't think it is something deliberate. I think probably some engineers knew about a few batteries & it never occurred to them that they should be contacting someone to get out a communication. (Because engineers .) But if it is truly an outlier situation (with negligible impact when it does occur) and not likely to impact most customers -- does it really belong as a normal operating issue to be aware of?

I'm trying to imagine all the disclosures this would require for different products if the bar were to be set there. I don't remember an ICE manufacturer meeting that bar - did any of them inform about how to properly break-in a new or rebuilt engine for a car you bought? Yet we all know we needed to do that for every single time, not just outlier cases.

So I guess where I stand now, based on the little actual facts we have, is that the truth lies somewhere in between and doubtful there was any malice on anyone's part - The OP has an issue, we don't (as yet) know how many could be impacted IF they were the same type of user, and if so, it appears the impact is negligible at best. We don't know how widespread because we also have anecdotal evidence of it NOT happening to others.

And I also wish people would stop the personal attacks, even when they think they're being subtle. (Spoiler alert - we see it.) Posts that have no purpose other than to insult people who disagree with them just bring this thread into the gutter.

 

[S3XY]

Hah!

TMC is a beehive of misinformation, speculation and spin. Tesla would have to be nuts to set foot in here.

Not if they want to control the message (as any company would).

 

[Matias]

Well, Jon did just the other day, on a service center mishap thread. This, of course, is a bit more dicey!

We also got response from Tesla in the Pack Performance and Launch Mode Limits

thread.

 

[AnxietyRanger]

@bonnie The thing that I find most interesting in this is, is this DC throttling a recent change or is it some always been there set of circumstances the car encountered and ended up throttling.

The Ludicrous counter throttling was a recent change, that is why outliers started popping up more and more. But we do not know yet if the DC charging is a recent change (we are seeing some recent reports of it as listed in message #385) or if it is simply coincidental that they are surfacing now.

I think this is an important part of the disclosing/intent angle. If this is a recent, deliberate change based on warranty/repair data, not disclosing it is probably worse than if this is just some set of battery management circs that cropped up in some cars over time.

So, it will be interesting to see if many people just started seeing this, or if it can be seen as something that simply cropped up over time.

 

[SageBrush]

Not if they want to control the message (as any company would).

There are much better ways to control the message without all the risks of being here.

 

[boaterva]

At the risk of being dismissed as just another cheerleader (but kind of hoping that includes cute outfits and pompoms), my two cents:

The OP likely has noticed a real issue with his battery, exacerbated by his unusual usage. My assumption is that Tesla Service correctly called that out on the repair order - but didn't give context as to how often this could happen, leaving this forum rife with speculation.

If it is widespread and going to happen to all, then yes, I agree with posters who feel this should have been disclosed - though I think it's more likely that an engineer, after the fact, discovered the problem through examining logs supplied by a service center & just replied to the service center as to what they believed. I don't think it is something deliberate. I think probably some engineers knew about a few batteries & it never occurred to them that they should be contacting someone to get out a communication. (Because engineers .) But if it is truly an outlier situation (with negligible impact when it does occur) and not likely to impact most customers -- does it really belong as a normal operating issue to be aware of?

I'm trying to imagine all the disclosures this would require for different products if the bar were to be set there. I don't remember an ICE manufacturer meeting that bar - did any of them inform about how to properly break-in a new or rebuilt engine for a car you bought? Yet we all know we needed to do that for every single time, not just outlier cases.

So I guess where I stand now, based on the little actual facts we have, is that the truth lies somewhere in between and doubtful there was any malice on anyone's part - The OP has an issue, we don't (as yet) know how many could be impacted IF they were the same type of user, and if so, it appears the impact is negligible at best.

And I also wish people would stop the personal attacks, even when they think they're being subtle. (Spoiler alert - we see it.) Posts that have no purpose other than to insult people who disagree with them just bring this thread into the gutter.

To comment on one part of Bonnie's post: the response from the engineer perhaps was not supposed to be quoted so directly. As one (engineer), I know I've been bitten by answers I send to people being just forwarded on (or pasted in, like this). 'You forwarded my email to the client?!' Of course, perhaps the engineer's statement was too broad or out of context. Do we know what their definition of DC Fast Charge is? Why didn't they say SpC or non-SpC? Lots of clarification to be made here...

So, as Bonnie says, we don't know if this is a global issue, an outlier, in between, some special circumstances, some certain batteries, whatever. Or it could be everyone and we need to know about it ASAP.

I would say right now, we don't have enough data. Too bad we don't have some insiders to talk to Tesla (like other companies seem to have on boards like this) to get the scoop before (!) this spins out of control.