If you fast charge, Tesla will permanently throttle charging

[zambono]

Thanks just saw it, what a mess. Tesla needs to stop adding restrictions after the fact and not letting owners know at time of purchase

 

[zambono]

A lot of things are bizarre in test-based non-chat conversations, because a single message has to target a lot more different angles (and people) than verbal or chat dialogue perhaps does at any given time. My underlining the fact that we do not know was targeting the notion that we know "5 minutes". Some people took that number as fact, sort of seemed to me including you, and ran with it. It is my view that we know far too little about that number to tout it as a fact. (Indeed, from Denmark we already heard of 7 minute delays as a practical example.)


Sure, a lot of people have said Tesla should provide us with more detail, but beyond that line there are very different approaches on what to do next. Some are understanding to the point that Tesla has no incentive to tell us more, on the other end I guess some are really trying to push Tesla to do the right thing and tell more by keeping their feet to the fire as @Canuck put it. It seems to me you are more in the first group, perhaps I am more in the latter group, though my personal things is more about finding the truth - that can happen without Tesla telling us too, by analyzing the data we get. You know me, analyzing the findings have produced results before, even when Tesla has no incentive to tell us (but we have an incentive to find out). E.g. @wk_057 is an extreme example of a person who finds out on their own...


Yes, it is something we do not know. What we do not reliably know is, what does Tesla know, because the precedent suggests a risk they would not be forthcoming with bad news until we find out about those bad news. Does analysis exist somewhere that suggest another step downwards in Supercharging capping is needed? Maybe Tesla could write an honest (not horse power kind) blog post about it all and alleviate our concerns. The precedent so far is that they will quietly implement counters/limiters etc. and only discuss them once they are forced by publicity. I see no change in this pattern, unfortunately.


If Tesla finds out about an unforeseen issue, that's what recalls and warranty repairs are for. We would expect no less from other companies.


Battery degradation over time is a well-communicated fact that even regular people can understand. If they want to make peak-charging "degradation" aka throttling a similar fact, then they should start by being very open about it before purchase and at the very least from the moment they find out themselves. As has been pointed out, not even this community knew about peak-charging throttling before the latest discoveries, so obviously this is not something that until now has been considered normal or communicated as a fact of life with battery electric vehicles.

Just as a reminder to you, Tesla even had a FAQ entry on Supercharging speed. Here is what is says. Considering that service centers apparently have been handing out knowledge about this for weeks or months already, we know Tesla has known about this, but apparently chosen not to mention it at all in any public material we could find out so far...


The fact that Tesla and several members on TMC seem reluctant to discuss this issue in public suggests to me some people may realize it has the potential to hinder adoption through creating apprehension about DC charging. But that would be a terrible reason to withhold information! The absolute worst. Besides being, just, well, wrong... it has the potential to backfire many times over, both for the company and for the mission.

You said it, it was never informed at time of purchase and it seems a company can't change specs after the fact to reduce warranty liability. Then again I don't think we were ever promised a minimum charge speed.

 

[techmaven]

Again, I'd like to see a full "degraded" charge curve. The area under the curve is more important than the peak.

 

[ODE90D]

The area under the curve is more important than the peak.

Not if you only charge a little to get all the way home.

 

[techmaven]

Not if you only charge a little to get all the way home.

Only if the peak corresponds to your SOC. Again, without the curve, we don't have enough info to really understand.

I don't believe this is something Tesla should have done, given what I guess is the curve. And I wonder if some engineer didn't come up with the algorithm correctly... heavy CHAdeMO adapter use might have been conflated with Supercharger use. Or they took a shortcut with a counter rather than measure something relevant, like the internal resistance. In any case Tesla needs to step up here.

 

[ODE90D]

Only if the peak corresponds to your SOC. Again, without the curve, we don't have enough info to really understand.

We have the curve - once you experience the reduced peak the charging curve has also changed. From then on your 90 kWh battery peaks around SoC 50%. So when we need a quick 20% from SoC 10% - 30% this leads to a dramatic increase compared to the original charging curve. Check here: Tesla Supercharging Speeds

 

[tomas]

If you DC fast charge a 90kWh pack too much the charging rate slows down a bit because of a Tesla counter.

The rest is speculation and extra detail surrounding the above core fact.

Be careful with the word "counter". None of us know exactly how they calculate and determine a battery's peak charge rate should be capped.

 

[electracity]

Was Dahn's battery longevity comments last week coincidental, or did Tesla just get lucky on the timing?

 

[electracity]

Be careful with the word "counter". None of us know exactly how they calculate and determine a battery's peak charge rate should be capped.

It's undoubtedly more complicated than a counter. For example, does the owner do a full charge and then let the car sit in that state.

 

[Shock-On-T]

The problem is the amount of data they show on the screen and their app. Many of you don't deserve that much. Just plug in and show the number of miles charged so far, with no indication of volts or amperes or time ro finish.

This is what every other EV does. Dumb it down Tesla !

Aaaand ... ignored.

 

[Shock-On-T]

The following wiki describes CHAdeMO (it actually means 'time for tea' in Japanese)
CHAdeMO - Wikipedia
Tesla makes an adapter to allow use with CHAdeMO stations, which are mostly sponsored by Japanese BEV makers, mostly Nissan, but also supplier by a number of third parties.
Tesla — CHAdeMO Adapter

Actually means "even tea", implying there is time for anything, such as some tea.
To be fair, it doesn't translate well.
Other possible translations would be:
"tea or whatever"
"how about tea?"
"tea anyone?"
"even a mere cup of tea"

 

[jbcarioca]

Actually means "even tea", implying there is time for anything, such as some tea.
To be fair, it doesn't translate well.
Other possible translations would be:
"tea or whatever"
"how about tea?"
"tea anyone?"
"even a mere cup of tea"

You're right, of course. I used 'time for tea' since my Nissan colleague and his TEPCO friend, while discussing CHAdeMO, suggested that 'time for tea' was the best translation of the intent, which was to imply that one might have sufficient time for a charge while having a leisurely tea. Since NISSAN itself meant essentially 'Japan daily manufacturing company' they can hardly be accused of being masters of a clever turn of phrase, especially when they're trying to make it work in multiple languages. Despite having worked in Japan frequently during the last 50 years, since 1967, I am accustomed to both ambiguity and unintended consequences in language, worsened because I lack personal expertise by which to judge such issues.

We agree, I think, that in the case of CHAdeMO they wanted to imply fast and easy charging.

 

[Shock-On-T]

You're right, of course. I used 'time for tea' since my Nissan colleague and his TEPCO friend, while discussing CHAdeMO, suggested that 'time for tea' was the best translation of the intent, which was to imply that one might have sufficient time for a charge while having a leisurely tea. Since NISSAN itself meant essentially 'Japan daily manufacturing company' they can hardly be accused of being masters of a clever turn of phrase, especially when they're trying to make it work in multiple languages. Despite having worked in Japan frequently during the last 50 years, since 1967, I am accustomed to both ambiguity and unintended consequences in language, worsened because I lack personal expertise by which to judge such issues.

We agree, I think, that in the case of CHAdeMO they wanted to imply fast and easy charging.

For sure, you are right too. There's no straight path from Japanese to English eh?

 

[AnxietyRanger]

Ok, no way I'm going to be able to read all the posts. Could someone kindly post a checkpoint summary of the major facts of this thread so far

Summary of first half's findings: If you fast charge, Tesla will permanently throttle charging #541

Tesla's response: If you fast charge, Tesla will permanently throttle charging #550

Electrek's article: Tesla explains why it limits Supercharging speed after high numbers of DC charges

Forbes' article: Use It, And Lose It: 'Clandestine Counters' Cause Tesla Revolt

 

[Electroman]

've seen as much degredation in the 90kwh battery that I did in the 85, but at only half the miles

Wondering if the additon of silicon is no

I've just started this thread, so pardon me if this has already been mentioned, but your battery is the first to introduce Silicon into the anode which is a known Lithium Ion battery degrader. The 90's have already, since the beginning had a faster taper than the 85s and Tesla has never explained how they got around increased degradation by using Silicon. I suspect that they didn't and this is their attempt to mitigate the issues caused by the Silicon enhanced chemistry.

Have any others seen the 90KW limit on 85s(not including the A battery which was limited to 90 KW from the very beginning)?

Most likely the case. I am guessing most of the range degradation and charge rate reduction are impacting 90kWh the most.

 

[McRat]

A thought.

While it could be a counter, it would be an engineering error. Using data from the pack such as coolant temp rise/min, internal resistance calcs, etc, is smarter. Because every 5 minutes you add to Supercharger duration increases the quantities of Superchargers necessary to service the fleet. I doubt they took this action blindly. In other words, there is a cost to benefit ratio to this. Warranty costs, vs. Supercharger funding. If a typical stay is 50 minutes, that's up to 10% more SCs needed at busy locations, which is significant. As the fleet ages, a counter would end up pushing vast numbers of cars into slow mode the problem gets worse with time.

Concerning the Model 3? The 21mm dia cell is harder to core cool than the 18mm. It will run hotter at the same C rate as the 18mm cells and the battery array will be smaller due to envelope and cost restriction.

And then will come the REAL litmus test. Will you buy a Model S that charges at 1/3 more MPH, or the Model 3 that charges slower? You sit at the chargers in the Model 3 and watch Model S's come and go why you wait, could push you to upgrade.

 

[supratachophobia]

If you ask me it is obviously a 90 kWh battery issue - and not a SuC counter thing as the “old” batteries with far more Supercharging are not affected. I wouldn’t be surprised if the peak on the 90Ds continues going south as the car ages because there is a problem with the new silicon anode and Tesla is doing this to avoid rapid degradation leading to warranty issues. So far my peak is reduced by approx 20% after 100.000 km in my 90D. Just wait for more high milage 90 kWh batteries and we will see that practically all are throttled.

For quite a while I have been asking for detailed SuC data from other Tesla owners in this forum, in the Danish teslaforum.dk, the Danish Facebook group and at Superchargers. Although the number of contributions to this analysis is low I have yet to come across something that contradicts my theory that only 90D are affected. You can view and enter data of your own here : Tesla Supercharging Speeds

I don't SC that often, but this weekend we are traveling. I'm interested to see what the SC rates are with 35k freedom units on the odometer. We still don't know if it's battery age, miles, or account if DC charges that is causing this slow down issue. It could be all three, it could be 1 or 2. We just don't know yet.

 

[tomas]

Summary of first half's findings: If you fast charge, Tesla will permanently throttle charging #541

Tesla's response: If you fast charge, Tesla will permanently throttle charging #550

Electrek's article: Tesla explains why it limits Supercharging speed after high numbers of DC charges

Forbes' article: Use It, And Lose It: 'Clandestine Counters' Cause Tesla Revolt

Cmon Ranger, even you have to agree that Forbes article is an exaggerated sensationalized piece that sows FUD using untruths. "Prevent you from charging your car at reasonably fast speeds"? Sheesh! If you want to argue Tesla should be transparent about what BMS does, fine. Hard to disagree. This deprivation stuff is - in this case - garbage.

 

[tomas]

I don't SC that often, but this weekend we are traveling. I'm interested to see what the SC rates are with 35k freedom units on the odometer. We still don't know if it's battery age, miles, or account if DC charges that is causing this slow down issue. It could be all three, it could be 1 or 2. We just don't know yet.

Let's not go back to square one please. We know that some algorithm in the BMS caps peak charge at 90 and that it relates to extremely high frequency of D.C. Charging. Tesla has confirmed that. That's what this thread is about, right?

The rest is conjecture at this point: 90 correlation, counter, etc.

Unless you D.C. Charge excessively, you will not encounter this. Everybody reporting their supercharging experience and attributing every sub 120 peak to this will just be noise and will feed the FUD.

 

[AnxietyRanger]

@tomas I made no comment on that by including it in the summary - I just tried to be thorough. It was a much discussed piece of commentary.

Here are a couple of more for @sorka to consider to get a quick feel for the thread...

Something is rotten in the state of Denmark: If you fast charge, Tesla will permanently throttle charging #745

Calculations about how many posts by each member: If you fast charge, Tesla will permanently throttle charging #802

Anything I missed?