If you fast charge, Tesla will permanently throttle charging

[AnxietyRanger]

Anyone who doesn't agree with you is ignorant?

Obviously not. There certainly are experts/informed people who also disagree with me. But we were talking about the non-initiated, were we not?

My point was: People unfamiliar, uninformed and unpassionate about something are usually appeased easier than those who are the opposite. Meaning experts are more likely to care about things within their domain, as opposed to non-experts. So, convincing someone who knows nothing about the Ludicrous counter issue, to use the example you yourself used, is more likely to be easier than convincing someone that knows everything about it. For a non-expert some quick quip about "flogging damage" can do the trick, someone knowledgeable and passiote can more easily find fault with that explanation.

Hence I agreed with @ohmman that less passionate audiences that volume sales bring, probably will be less of an issue for Tesla regarding specific, information-loaded grievances such as this. (There may be some other types of grievances where that audience is less forgiving than the enthusiasts, though, but Supercharging peak rates is not IMO likely one of them.)

 

[thefortunes]

Ok, so here goes!

Hopefully this sheds a little more light on the subject. I still need to do calculations on the actual loss in minutes for different charge cycles, but I'm in a rush for a meeting so it'll have to wait

Preparation steps:

• Enjoy driving the best car I've ever owned around until estimated SoC at supercharger arrival was approximately 0%.
• Ensure battery was warm at arrival (I drove at ~110-130km/h highway speeds for 52 minutes prior to arrival at the supercharger…try not to exceed the speed limits…must…try…)
• Call Tesla European service center, supercharger department, to verify which pairs had the highest output: pairs 3 and 4, output 135 kw.
• Pray one of the two pairs was available upon arrival... It worked and I had 3A and 3B all to myself for the test ;-)
• Boot laptop and be ready to take notes.
• Connect to supercharger.
• Rush into car and be ready to start the timer when the charging starts.
• Try not to pee my pants while completing a charge cycle to 80% (success again, but definitely the hardest part of the data gathering!)

Other data:

• Tesla Model S P90D with Ludicrous option, December 2015.
• Ambient temp 8 degrees C.
• Most of the data points are in taken in 5% intervals as there is little-to-no change in kW. However some of them do change dramatically, like from 5% to 6% where it increases from 62 kW to 86 kW, and 58% where it starts tapering off faster - so I added a these datapoints manually where I deemed relevant in addition to the 5% increments.
• If the kW was "flickering" between two numbers (like going from 87 kW to 88 kW and back and forth very fast) I added the higher of the two while collecting data.
• kW (not kWh!) is measured at the beginning of the SoC percentage.
• Minutes is rounded to half-minute increments and noted at the beginning of the SoC percentage.
• In case anyone cares, the cars cooling fans were audibly "loud" from around 30% to 55% IIRC.

For comparison, even though I do not have the facelifted version, I previously used to have the charge curve of the "90D new" as mentioned in Bjorn's data:

Tesla Ups Supercharger Charging Rate For Refreshed Model S 90D & P90D - Video



SoC kW Charge time
0% 50 0
5% 62 4,5
6% 86 5
10% 88 7,5
15% 89 10,5
20% 90 13
25% 91 15,5
30% 92 18,5
35% 94 21
40% 95 24
45% 96 26
50% 97 28,5
55% 90 31,5
58% 85 32,5
60% 81 34,5
63% 74 36
65% 72 37,5
67% 68 38,5
70% 60 41
73% 53 43
75% 48 45
77% 44 47
79% 40 49,5
80% 40 50,5
85% 34 57
87% 32 60
90% 28 64,5

FYI, for those scoring at home, EVEN WITH "THROTTLED" SUPERCHARGING RATES, he charged from 10% to 80% in 43 minutes (vs the "typical" 40 minutes that Tesla states on their website).

OMG, what a tragedy!

 

[AnxietyRanger]

WITH "THROTTLED" SUPERCHARGING RATES, he charged from 10% to 80% in 43 minutes (vs the "typical" 40 minutes that Tesla states on their website).

Thank you for the calculation. So 7.5% slower than advertised and on the low end of the 3-7 minute impact spectrum for DC charging peak rate throttling discussed on this thread.

I look forward to @torvalstrom returning with commentary on how this compared to his pre-throttling. It will be interesting to see where that 7 minute figure he has used himself comes and how Tesla's ~5 minute statement fits in with all that.

 

[Kgdietz]

FYI, for those scoring at home, EVEN WITH "THROTTLED" SUPERCHARGING RATES, he charged from 10% to 80% in 43 minutes (vs the "typical" 40 minutes that Tesla states on their website).

OMG, what a tragedy!

Sure, three minutes isn't a big deal. But does it end there? A week ago I knew nothing of any limit, now there is one, and it's poorly defined. I think the original poster hit this limit at 30,000mi or so, will there be a new, lower limit for him at 60k, 90k? What will the new limit be? Are their other limits yet to be found? We've been told you can daily charge up to 90%, will it come out later that there is some limit because someone always charged to 90% that wouldn't be there if they had daily charged to 80%? What about L2 charging rates? I charge at 32A/240V every night, would it be better in any way if I charged at 20A/240V (either rate gets the job done for me on 95% of nights)? I would have confidently said, "no", last week. Today I wonder.

Ken
'15 S 70D

 

[McRat]

Ok, so here goes!

Hopefully this sheds a little more light on the subject. I still need to do calculations on the actual loss in minutes for different charge cycles, but I'm in a rush for a meeting so it'll have to wait

Preparation steps:

• Enjoy driving the best car I've ever owned around until estimated SoC at supercharger arrival was approximately 0%.
• Ensure battery was warm at arrival (I drove at ~110-130km/h highway speeds for 52 minutes prior to arrival at the supercharger…try not to exceed the speed limits…must…try…)
• Call Tesla European service center, supercharger department, to verify which pairs had the highest output: pairs 3 and 4, output 135 kw.
• Pray one of the two pairs was available upon arrival... It worked and I had 3A and 3B all to myself for the test ;-)
• Boot laptop and be ready to take notes.
• Connect to supercharger.
• Rush into car and be ready to start the timer when the charging starts.
• Try not to pee my pants while completing a charge cycle to 80% (success again, but definitely the hardest part of the data gathering!)

Other data:

• Tesla Model S P90D with Ludicrous option, December 2015.
• Ambient temp 8 degrees C.
• Most of the data points are in taken in 5% intervals as there is little-to-no change in kW. However some of them do change dramatically, like from 5% to 6% where it increases from 62 kW to 86 kW, and 58% where it starts tapering off faster - so I added a these datapoints manually where I deemed relevant in addition to the 5% increments.
• If the kW was "flickering" between two numbers (like going from 87 kW to 88 kW and back and forth very fast) I added the higher of the two while collecting data.
• kW (not kWh!) is measured at the beginning of the SoC percentage.
• Minutes is rounded to half-minute increments and noted at the beginning of the SoC percentage.
• In case anyone cares, the cars cooling fans were audibly "loud" from around 30% to 55% IIRC.

For comparison, even though I do not have the facelifted version, I previously used to have the charge curve of the "90D new" as mentioned in Bjorn's data:

Tesla Ups Supercharger Charging Rate For Refreshed Model S 90D & P90D - Video



SoC kW Charge time
0% 50 0
5% 62 4,5
6% 86 5
10% 88 7,5
15% 89 10,5
20% 90 13
25% 91 15,5
30% 92 18,5
35% 94 21
40% 95 24
45% 96 26
50% 97 28,5
55% 90 31,5
58% 85 32,5
60% 81 34,5
63% 74 36
65% 72 37,5
67% 68 38,5
70% 60 41
73% 53 43
75% 48 45
77% 44 47
79% 40 49,5
80% 40 50,5
85% 34 57
87% 32 60
90% 28 64,5

You are just barely off their claimed charging rate. The Tesla website description says 10% to 80% in 40 minutes when referring specifically to the 90kWh pack:

"Charging from 10% to 80% is quick and typically provides ample range to travel between most Superchargers. Charging from 80% to 100% doubles the charge time because the car must reduce current to top off cells. Actual charge times may vary." - Graphic shows 40 min at 80%, a little misleading.

You took 43 min. Then they say Up To 170 miles in 30 min. It took 32,5 min to reach 58% (170mi) of a MS 90D's EPA range of 294 miles.

No opinion on the situation, but they are normal variations of that kind of instrumentation. ie - is it really 80%? is it really 58%?

 

[AnxietyRanger]

Semi-serious question Anxiety - are you getting paid by the post? In the last 26 posts in this thread, 13 are yours where you have rehashed either what you have already said multiple times or rehashed what someone else said (like my previous post). Why?

That's the nature of conversation, people write and people get answers. The more people write, the more they get answers and so it goes. I am active in threads that interest me. The other one I am active at the moment in is this: AP2.0 Cameras: Capabilities and Limitations?

Now, if someone wants to pay me for doing what intrigues me, I am taking offers. But to answer your question: sadly, no, I am not getting paid by the post nor am I getting paid at all for this. I mean, think of the $$$ potential if I were!

 

[thefortunes]

That's the nature of conversation, people write and people get answers. The more people write, the more they get answers and so it goes. I am active in threads that interest me. The other one I am active at the moment in is this: AP2.0 Cameras: Capabilities and Limitations?

Now, if someone wants to pay me for doing what intrigues me, I am taking offers. But to answer your question: sadly, no, I am not getting paid by the post nor am I getting paid at all for this. I mean, think of the $$$ potential if I were!

I understand contributing to discussions that interest you, and you (and I) certainly have done that here. However there are times where you are just restating what others post and that makes the thread long and unwieldy for the average user to navigate. (I certainly have done the same at times, but I have tried to do it when a point has been lost and someone asks a question that was answered 45 pages earlier ).

All I am saying is consider whether what you are about to post is adding to the conversation or is just a rehash.

Probably should have been discussed via PM, sorry.

 

[AnxietyRanger]

You are just barely off their claimed charging rate.

Well, whether or not ~8% is barely is debatable. We do know his peak rate stays at around 90 kW, while normally it would have gone above 110 kW.

No opinion on the situation, but they are normal variations of that kind of instrumentation. ie - is it really 80%? is it really 58%?

I find this line of questioning rather dismissive, considering Tesla admitted to throttling and a delay of ~5 minutes themselves. So obviously this is not nothing, data-wise. There is a throttling going on and this data suggests it as well.

Whether or not it is significant is, of course, a matter of opinion.

 

[whttiger25]

Does anyone know anything about the cell chemistry/silicon content/potential throttling issues on the 100 kWh battery?

 

[Pruitt]

... I think the original poster hit this limit at 30,000mi or so, will there be a new, lower limit for him at 60k, 90k? What will the new limit be? Are their other limits yet to be found? ...
Ken
'15 S 70D

Excellent point, Ken! There well may be other, more severe limitations on charging rates as batteries age and degradation accelerates. I would venture to bet that Tesla's engineers don't know that yet, though they probably have some inklings by now as to the eventual necessity of additional limitations.

... So, convincing someone who knows nothing about the Ludicrous counter issue, to use the example you yourself used, is more likely to be easier than convincing someone that knows everything about it. For a non-expert some quick quip about "flogging damage" can do the trick, someone knowledgeable and passiote can more easily find fault with that explanation.

You and I are in agreement on this one. I point out, though, that exactly what you know about may impact how grievously you view the counters. Being a mechanical / structural engineer, I can easily understand the need for the reduced performance after so many "launches." The vehicle components can only take so much before they start to fatigue. Yes, they could be redesigned to handle the high power throughput indefinitely, but the cost is in both weight and dollars, so you wind up with perhaps a significantly more expensive vehicle without any appreciable improvement in performance (as you've lost the gains by having to accelerate all that extra weight).

Should Tesla get out in front by disclosing all these things? Probably, but with many outlets already reporting half-truths to Tesla's detriment, I can understand their reluctance to do so.

 

[anticitizen13.7]

All current S/X batteries use the same 18650 cells with the same chemistry - 75, 90, and 100. The 100 uses different modules which pack more cells per module.

And you know that as a fact because? Have you torn down all the packs and compared the cells?

Are you sure about that? Elon Musk said it was for "upgraded packs" back in 2015:

I think at that time these were new cells being produced, and it was experimental "baby steps", and thus perhaps they were only going into the 90 packs, since there were no 100 packs at that time, and he said it was chemistry for the "upgraded packs".

I hate to throw fuel on the fire (since I don't even really see this as a fire) but I'm not convinced that Tesla stuck with silicone once it appeared the 90 packs were degrading faster than the old 85's. Also, @JonMc from Tesla told us it affects less than 1% of customers so it seems pretty limited in scope. But this is all just pure speculation on my part.

I miss the old days when we could discuss interesting things like this here without dramatic replies equating to Tesla is the devil, or conversely, is a saint, since Tesla is neither. It's just a corporation that is run by humans -- so it's flawed, like the rest of us.

On the question of what cells the 75 kWh and 100 kWh packs are using...

There is a way to infer the chemistry of the cells using existing data, but this is not 100% reliable.

(1) We know the actual specified kWh capacities of Tesla packs, thanks to work from wk057: Tesla, please stop making up specifications... | wk057's SkieNET...
And: Pics and Info: Inside the Tesla 100kWh Battery Pack | wk057's SkieNET


wk057's data from packs relevant to my calculations are:

• 85/P85/85D/P85D - ~81.5 kWh total capacity, ~77.5 kWh usable
  
• 90D/P90D - ~85.8 kWh total capacity, 81.8 kWh usable
  
• Original 70 - ~71.2 kWh total capacity, 68.8 kWh usable
  
• 75/75D - 75 kWh total capacity, 72.6 kWh usable
• 100D - As for real capacity, the BMS reports usable capacity at a whopping 98.4 kWh. It also reports a 4 kWh unusable bottom charge, so that's 102.4 kWh total pack capacity!

(2) We know the number of cells per pack, again thanks to wk057's pack teardowns:

Tear down of 85 kWh Tesla battery pack shows it could actually only be a 81 kWh pack [Updated]

• Tesla’s “85” kWh pack consists of 16 modules of 444 cells for 7,104 total cells.

wk057 also observed that in the 100 kWh pack, there are 516 cells per module, 16 modules, and a total of 8256 cells.


(3) Calculations:

(3)(a): 90 kWh vs. 85 kWh
As far as I know, the 85 kWh and 90 kWh packs have the same number of cells. The difference in capacity is due to the chemistry inside the cells. So the difference in capacity per cell can be calculated by simply dividing the total capacity of the 90 kWh pack by the total capacity of the 85 kWh pack: 85.8 kWh / 81.5 kWh = 1.05276... which means that the newer silicon additive cells have about 5.3% more capacity than the classic graphite-only cells.

(3)(b): 75 kWh vs. 70 kWh

The original 70 kWh battery (NOT software locked model from May 2016) dates back to April of 2015. It most likely still uses the older chemistry, because the "experimental" 90 kWh pack with the new chemistry was not announced until July 2015. The 85 pack continued to be sold for awhile even after the 90 became available.

The ratio of nominal capacity between the 75 and 70 packs is 75 kWh / 71.2 kWh = 1.05337... which implies that the newer pack has 5.33% more capacity per cell than the older pack. The ratio of the 90 to 85 pack is virtually the same as the ratio of the 75 to 70 pack. CAVEAT: I do not know that the # of cells in the 70 pack is the same as the # of cells in the 75 pack.


(3)(c): 100 kWh vs. 90 kWh
The 100 pack has nominal capacity of 102.4 kWh divided among 8256 cells, or 0.012403 kWh/cell
The 90 pack has nominal capacity of 85.8 kWh divided among 7104 cells, or 0.012077 kWh/cell
The 85 pack has nominal capacity of 81.5 kWh divided among 7104 cells, or 0.01143 kWh/cell

We can see from these figures that the 100 pack derives its greater capacity from both higher # of cells, and greater energy density.


Conclusions:

I believe that there is a strong possibility that the 75 battery uses the same chemistry as the 90 battery, based on comparison of the ratio of energy stored between the 90 and 85, and the 75 and 70. Again, the unknown here whether the # of cells in the 75 pack is the same as the # of cells in the 70 pack.

I also believe that the 100 pack uses a slightly different chemistry than the 90 pack, because the energy density of 100 pack cells is higher than that of the 90 pack cells.

 

[SageBrush]

Since Tesla states the car is functioning as designed, there is nothing to disclose

You sure about that ?

 

[AnxietyRanger]

@anticitizen13.7 Superb info and decucting! Love it.

 

[anticitizen13.7]

Other considerations to my post on battery chemistry:

It is also possible that Tesla has tweaked the chemistry, battery design, or manufacturing process of the battery cells with the silicon additive over the past 2 years. There is no way for me to determine that the cells used in original 90 packs are the same as the cells used in 90 packs today, even if they have the same nominal energy capacity.

 

[boonedocks]

Indeed! And I'm as keen as anyone to find out all the details. I'll be a bit shy of superchargers until I do

Looks like the motherships master plan to curb SuperCharger usage IS going to work!!!!

Just kidding

 

[AnxietyRanger]

Does anyone know anything about the cell chemistry/silicon content/potential throttling issues on the 100 kWh battery?

@anticitizen13.7 just wrote an interesting post about that: If you fast charge, Tesla will permanently throttle charging #1095

 

[AnxietyRanger]

Looks like the motherships master plan to curb SuperCharger usage IS going to work!!!!

Just kidding

Yeah, I'll be steering well clear of those dangerous places! I'll leave the idle charges, peak rate throttling and fast food to the hoi polloi. I'll seek the premium experiences of slow AC charging, slow fine dining and by the minute parking somewhere nice...

 

[ohmman]

Thanks @torvalstrom for the data. I think I'm unwatching this thread for the obvious reasons but will follow your future posts in case you're able to supply more concrete data.

I'm off to hang out with my ignorant friends who foolishly love their Teslas.

 

[RubberToe]

FYI, for those scoring at home, EVEN WITH "THROTTLED" SUPERCHARGING RATES, he charged from 10% to 80% in 43 minutes (vs the "typical" 40 minutes that Tesla states on their website).

OMG, what a tragedy!

Definitely going to be litigated before the Supreme Court. Expedited review!

RT

 

[Zythryn]

Well, whether or not ~8% is barely is debatable. We do know his peak rate stays at around 90 kW, while normally it would have gone above 110 kW.


I find this line of questioning rather dismissive, considering Tesla admitted to throttling and a delay of ~5 minutes themselves. So obviously this is not nothing, data-wise. There is a throttling going on and this data suggests it as well.

Whether or not it is significant is, of course, a matter of opinion.

No, the data does not indicate that. Nor do we know the charge normally would go above 110kW.
We need the baseline data as well. Is this any slower than when the car was new?
Would a different car with the same battery model, charge any faster?
What other variables were involved? What if the test was repeated when it was 20 degrees rather than 8?

From the original OP we have an edge case where the car is charged 99% of the time with D.C. charging.
We also have reports of many other people that have had their cars longer with no apparent throttling.

To test this, we need a variety of 90kWh cars to test with the same SC. Or, one 90kWh car tested over time.

The only supported conclusion I see right now is if you drive as many miles as the OP with 99% supercharging the rate of charge of future SC may be limited by a small percentage.