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If you fast charge, Tesla will permanently throttle charging

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Tesla should put a large warning label on their $450 Tesla to CHAdeMO adapter: "Don't use this for over xx miles or it'll degrade your battery and we'll throttle you without telling you."

Speak directly. Be honest. Treat people fairly. Didn't we learn these things in kindergarten?

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So what should OP do? Who does he appeal to? That RO says "According to Tesla engineers"...so, who is next in line that needs to be informed?
 
I kind of wished tesla showed the Amp charging like the old app. This way you can easily tell because that would tell you how fast you are filling up the electrons.

Maybe the KW change is a way for tesla to hide this slowly degrading effect.
I think you are a bit confused about the meaning of electrical terms.
Kilowatts is in fact the measure of how much electrical energy you are receiving at the moment; analogous to gallons per unit time of liquids. That is why your battery capacity is rated in kWh, the electrical analogue of gallons of gasoline in your tank.
Amps is a measure of current; analogous to size of a water pipe.
Volts is a measure of electrical potential; analogous to water pressure.

A certain rate of kilowatts of power flow can be achieved by either higher voltage at lower amps (high pressure, small pipe) or lower voltage at higher amps (low pressure, big pipe). Before Tesla changed the display to k/W, we had to mentally multiply the amps by the volts in order to see how fast our batteries were charging.
 
The lack of disclosure is, sadly, becoming less surprising. I'm hopeful Tesla will start to move away from doing this stuff quietly without owner awareness. It's best we know up front, but if they discover something later, just let us know.

Agreed. Seeing these counter-type issues come up is very disappointing. One would think they learned their lesson from launch counter-gate. Stop counting things Tesla!!! o_O
 
If you read the notes from the service center posted up above, this seems to be only concern regarding CHAdeMO charging. Apparently has nothing to do with supercharging.

Where do you see that?
It reads "... vehicle has been DC fast charged over specified amount, the battery management system restricts DC fast charging to prevent degradation of the battery pack".... "is now has permanently restricted DC charging speeds". also ..."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 changing performed on the pack up to this point in time"

Where do you see that it's "only concern regarding CHAdeMO charging"? CHAdeMO is DC but so is Supercharging. The note simply says that supercharging will always be available but it is silent on the speed or tapering of supercharging, which could be interpreted either way, but it definitely does not state that it's not tapered.
 
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The other possible source of confusion that various people have mentioned here is that this potential limitation might only affect the newer batteries, which may or may not have newer battery chemistry. Has it actually been confirmed that Tesla is using different battery chemistry in the newer packs?
 
Yes, I would absolutely opt out of it. My time is far more valuable than a theoretical battery degradation years down the road. Right now, losing 25 kW of charging capacity costs me about 10minutes extra per stop, from the few Superchargers I have tracked on road trip routes I have taken before and after this issue came to light. This all adds up...

In an ICE, I will typically drive 300 - 600 miles without stopping, so it takes me about 9 hours to go a full tank of fuel and I may or may not stop between tanks. I have to stop every ~100 miles or so in the Tesla and charge, increasing my trip time by 30 - 70%. Now, with this added burden, that piles on another ~25 - 30ish% of stop time. The Superchargers I frequent are in the middle of nowhere with nothing around to do, so I have to sit around and wait to charge the entire time. There is only so much eating I can do every 90 minutes. The additional 10+ minutes per stop is exceedingly painful on top of an already painful experience.

There is no driving less distance each time. I MUST stop every ~100 miles. I can't skip a Supercharger. They are too far apart to skip one, even in a 100D - so you MUST stop at each charger and charge, usually for a minimum of 15 minutes... now 20+ minutes. On the last road trip I had 2 SC stops (KC to STL), previously, it was a 15m and 20m stop. Now it was 25m and 30m stop. To be fiar, the last charge in the KC to STL direction is to have enough power for the destination travel, but on the way back, the last charge is actually required to get the whole way home, that time was increased from 15m to 25m.

I opted for the 90 instead of the 85 for the increased range (and presumably less charging time) - I would have waited for the 100 if I had known it was coming. The charging time was a specific criteria I used in purchasing the car, and the car delivered on that in the beginning. It is no longer delivering on that. I will trade charging time for range any day of the week. Hell, I'll take a 150 mile range for a 5m charging time at each stop. That is absolutely a trade I would be willing to make.
Likewise, I'd like to opt out of early degrading my battery. I don't need every D.C. charge session to be super fast. I just need charge to get to destination.
 
Yes, the software should track "area under the curve" and not a binary number of charging sessions. Very lazy programming if it is true.

Exactly lousy programming. If OP's issue happens only with CHAdeMO, it could be that the counter simply counts the charging power spikes regardless rather small current, and maybe there're multiple small or big ramps during a CHAdeMO charging session. I don't have equipment or fixtures to measure charging power curves (kW vs. time) for CHAdeMO charging a Tesla, not sure if some of us can do (I am not hoping the company to test so).

The company needs to be more and very transparent on the products it sells.
 
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So are you saying that it takes a higher rate than 90 kw in order to achieve an 80% charge in a 90kWh battery in 40 minutes? I'm not familiar with the math, but is it basically 90 X 2/3 = 60 which would only be a 66 2/3% charge?

No, I'm saying that there is no disclaimer on the charging rate as of today. If you have a 90kWh battery, you should get 80% in 40 minutes when things are working correctly. It doesn't have any exception limiting it, like 'up to' or 'for XXX charges'.

If his 90kWh does not get 80% in 40 minutes on a fully operational Supercharger due to known software feature, they are in error on the specification. That's all I'm saying. If a limit does exist, they need to mention it before you buy, not after.
 
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Sure I can read.
Sarcasm noted. The alleged report is indeed formatted like the Tesla Service reports, but there is no assurance that said report is genuine.
I not only can read, but I can fact check and think.
So you're suggesting a conspiracy theory? Jon McNeill (@JonMc) has been copied on this thread several times, he could shut that down in an instant.
 
It's not confirmed. Some reporters are confusing seasonal variations (winter vs summer), some neglecting Supercharger Tesla density, i.e. slower charging if somebody else is charging in a paired position. Some get erroneous information. Possibly somebody is inventing a story.

Tesla does NOT arbitrarily cut DC charging rates available to a given car. In any event CHAdeMO cannot presently present a fast charging consequence that will damage battery packs of any Model S or X.

We are all trying to be polite here, as we should. However, this thread is spreading nonsense and distrust where it should not be.

If there were such an issue all the high mileage constant Supercharging Teslas would have such limits. Nobody does.

THE CLAIM IS NOT TRUE.

Sorry for shouting. It's time to stop spending BS. If the OP finding actually happened it probably was seasonal. As for an alleged Tesla report conforming that, if it happened the employee should be counseled or fired.

Sure I can read.
Sarcasm noted. The alleged report is indeed formatted like the Tesla Service reports, but there is no assurance that said report is genuine.
I not only can read, but I can fact check and think.

I just spoke with a Kansas City Service Center person who suggested that battery pack "H" might have some degradation due to extreme high DC charging, although he also stated that users could very rarely even perceive such. Checking with Tesloop reporting, among other, shows nothing like this. I do now think it is possible that somebody in KC wrote that, maybe even the guy I spoke with, since he seemed familiar.

Otherwise I still, stand by my earlier post.

You, sir, are enigma. After calling the OP a liar and his claim a "BS", you, by your own admission, spoke with a Tesla person (I wonder if you purposely not including the title of that "person" to further belittle the confirmation) who confirmed the claim of the OP. But, you go out to super-Tesla-authority Teslaloop for a definite and final refutation so you can "stand by you earlier post".

I mean, there is nothing wrong to be sceptical, especially on the internet, but I think the issue of this thread is shaping out to be a real thing and the OP deserves some attention. The similar issue is also discussed here [Rumor]Tesla is reducing speed of Supercharging as your Tesla gets older
 
As with all things Tesla, this design appears to have been implemented to reduce Tesla's exposure to warranty claims. Yet another reason to take Tesla representations with a huge helping of salt because, as the old saying goes, YMMV.

As with all things Tesla, this design appears to have been implemented to give you an extended working life for your battery and availability of range. Yet another reason to be confident that Tesla's car are built to last for years unlike competitors EVs.

The amazing much reduced degradation that we all try and boast proudly, doesn't happen magically. That is all due the excellent battery management and the software that goes along with it. KUDOS to Tesla.


If you have a 90kWh battery, you should get 80% in 40 minutes when things are working correctly. It doesn't have any exception limiting it, like 'up to' or 'for XXX charges'.

.. when new. As with all things, performance on all fronts is expected to degrade as the car gets older. Your ICE car is not as smooth and as zippy at 100K as it was when new. That is why older cars sell for much less price than newer ones right out of the dealers lot.
 
No, I'm saying that there is no disclaimer on the charging rate as of today. If you have a 90kWh battery, you should get 80% in 40 minutes when things are working correctly. It doesn't have any exception limiting it, like 'up to' or 'for XXX charges'.

If his 90kWh does not get 80% in 40 minutes on a fully operational Supercharger due to known software feature, they are in error on the specification. That's all I'm saying. If a limit does exist, they need to mention it before you buy, not after.

Ok, so as long as you are getting to 80% in 40 minutes no problem then. Even if it is possible to get to 80% in 35 minutes at a faster charge rate, if they slow you down so it takes 40 minutes in order to protect the battery that isn't an issue. Got it.
 
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There is also a steering angle sensor counter and a brake pressure counter. The more turning or slowing down you do, the more you increment these counters. In order to save premature wear on the steering gears and brake components, Tesla will gradually limit your ability to make sharp turns or apply excessive brake pressure.

Of course, this is all done to preserve the "user experience" and make the car stay enjoyable in the long run. Please plan changes to your routing and following distance accordingly.

That's funny, I used a similar example on the phone with them yesterday. I said the wipers will start slowing down after a set number of wipes to preserve the wiper motors from degrading and that the brakes will stop working as well to preserve the life of the brake pads. It's just as silly, or is it?

According to EV Trip Planner, it is 212 miles from the KC to the St. Louis supercharger. That should be easily do-able in a 90D (with no bad weather) without having to stop in Columbia. Driving at 65 instead of 70, will cost you about 15 minutes and save a charging stop of about the same duration.

Several things here - first and foremost, I live 40 miles east of the Independence Supercharger, so I would need to stop at the Independence SC and top up to 100% (which would take forever) to make it from Independence to St. Charles. Secondly, that would be assuming a) perfect weather and b) no cargo load. My P90DL MIGHT get 212 miles with perfect conditions @75 MPH, but I would arrive at the St. Charles SC with low single digits remaining in the battery. If anything bad happened or there was rain, I'd be screwed. More importantly, though, I don't travel that route alone, so I have at least 1 other person, if not 3 + the associated luggage.

Where does one find charge session logs?

I use Teslalog.com ... but there is a couple other services out there that you can use as well.

The lack of disclosure is, sadly, becoming less surprising. I'm hopeful Tesla will start to move away from doing this stuff quietly without owner awareness. It's best we know up front, but if they discover something later, just let us know.

Regarding this specific issue, there are some outstanding questions. One of which is whether or not the peak rate continues to diminish, and if so, what's the formula for that reduction? Another question I have that @Naonak can answer is whether the curve is flat at the beginning now, and then tapers in conjunction with the original curve, or if it tapers immediately. I assume the former. Tesla is trying to keep the battery from exceeding a particular C rate, so capping without disturbing the taper curve makes at least some sense.

I have a hard time coming up with 10 minutes in theoretical calculations. Do you have some data that we can reference? It looks more like 3-5 minutes from what I can tell. 5 minutes if the taper curve begins immediately, and 3 minutes if it's capped. But that's really just eyeballing a charge from 10% to 90%. This experiment was done in the past by @Owner with the 90kW "A" packs vs. the 120kW capable packs and they came up with 4-5 minutes.

I'm not suggesting we discard your complaint, but it's useful to be accurate about the time difference per charge at the reduced rate.

I only have one definitive set of datapoints to extrapolate the power curves at the moment, since I haven't taken an road trip since last November and used Superchargers. Also, Teslalog doesn't seem to be showing the amps any longer (removed from the Tesla API) so I'm not sure how to calculate an accurate power curve retroactively now. I didn't think to time the ramp down while watching the car. I have TM-Spy and the cables, I will be hooking that up next time I SC and recording from there.

With regards to the 10 minutes, again, I only have effectively one data point. I compared my charge time from my last KC - STL - KC trip the same time last year (and same weather conditions). So it's probably got some fudge factor, but I agree the math should show a lesser increased time, but the increased charge time estimated by the car is what initially tipped me off to this problem - The first charging stop was estimated to be in excess of 40m! When previously it was around 25m if I recall... actual charge times are slightly different, but it was significantly longer than previous stops. I'm missing some data because the St. Charles SC was experiencing habitual problems last year, so any data from that particular SC is useless, so I effectively only have the Columbia datapoint to compare. This most recent Columbia charge took 47m to go from 18% to 88%. The previous Columbia charge took 25m to go from 41% to 72% ... so it's not really a comparable stop, unfortunately.

I am doing the KC - DEN - KC trip in a few weeks will give me a lot more comparable data points to use compared to last year, so should produce much more informative data.
 
I won't go off the handle on this as I tend to do...

What I will say is Tesla, PLEASE, PLEASE, PLEASE stop doing this and just be honest and up front with your customers. Keep us in the loop when you introduce these new software "features"... This wouldn't be as big of a deal if you were up front and honest about things...

I would really love to know who's making these decisions within Tesla Motors... It can't be Elon, this is one of those lower level decisions. Whomever thinks that secretly introducing these software limitations without full disclosure and then simply waiting to see if anyone notices, is really a fool. We're all going to notice at some point.

Again, just be honest and up front. Why is that so hard?

Jeff