If you fast charge, Tesla will permanently throttle charging

[ohmman]

I can handle the innovation but in case you haven't noticed the newer people are getting more and more demanding and less and less tolerant than we are and I doubt Tesla, in its' current state, can support 500k new demanding angry owners per year.

Outside of this bubble, I think you'll find that the owners are much, much less angry. I think on TMC there are maybe one to two dozen angry owners. Seriously.

I met a woman locally who has a very early X. It looks to me to be, let's say, compromised. I parked next to her and asked how she likes and it and she told me it's the best car she's ever owned. Assuming she was a newish entrant to Tesla, I told her we also had an X with the same configuration as hers, but also my S that was parked there. She said she had an early S as well. Well, there you go.

Social norming here has caused us to look at things in a different way, and it's not necessarily indicative of future customers. Enthusiasts are the biggest fans and the biggest critics.

 

[Shock-On-T]

Just a small correction. It's silicon, not silicone.

I thought my implants felt funny...

 

[Shock-On-T]

Many variables can affect SuC rate - your SOC, battery pack temp, ambient temp, handle age, contact cleanliness, etc...

In addition, I have read (too lazy to confirm since it doesn't apply to me) that the 75 kWh packs (and software-limited variations) can only charge at a max of 96kW due to the number of cells.

All of this is discussed in the other (50+ page thread).

I can add my single data point. I've never had more than 98kW charge speed with my 75D, and usually 90kW.

 

[Matias]

I can't imagine that Telsa has ever guaranteed a particular charge rate. Especially since we know that will all depend on a number of factors.

 

[stopcrazypp]

View attachment 226150

Says "Actual charge times may vary" here. There may be one place if you dig very deep that they might have missed the disclaimers by accident, but in general I would expect almost all places would have it.

In practical terms, they can't guarantee a given charging speed (even in absence of this limiter) due to factors already covered here (temperature, stall sharing, supercharger cabinet issues, etc), so I doubt they would stick their heads out and make an absolute statement guaranteeing a given charge rate.

 

[whitex]

I'm actually okay with slower supercharging as it gives me more time before having to rush down to the parking garage to move my car, even if the trade-off is longer waits during peak charging times.

Given your sentiment, I would suggest plugging in to a nearby 110V socket to maximize the time you have before you have to move the car.

 

[whitex]

Sound like these types of warranty claims are exactly what tesla is trying to prevent. What will be more interesting is if you see lots of slower supercharging in the future

Can reduced supercharging be a warranty claim in itself? You paid for a car capable of 120KW charging, suddenly it can only do 75% of that. Should it be considered broken? It is a part of the drivetrain+battery system. Tesla charges $1,900 for charger upgrade from 48A to 72A, so charging capabilities obviously have monetary value (at that rate the 30KW reduction should be worth roughly $10K).

 

[stopcrazypp]

Ok. Well a couple things. Are we sure this effect is related to the thermals? The cooling system really doesn't have much trouble keeping up with the heat generated by the cells even in warm weather. I suspect it could be something else related to the C rate and the first gen silicon cells.

Also, yes regen is for a short period, but it accumulates. For my car I wouldn't be surprised if I regen'ed at 60 kw more than I supercharged at 60+ kw for the life of the car.

It's not going to be pure thermals. It'll be something like charging C-rate + temperature + SOC + DOD + time spent at that condition. Temperature is just one of the variables there. Charging and discharging like during regen, and spending a long amount of time charging, is going to be very different in terms of effect on the battery.

The principle that is working is similar to how partial cycling can drastically improve battery life (equivalent full cycles) versus deep cycling.
Increasing the cycle life of lithium ion cells by partial state of charge cycling
We commonly use the equivalent of 2 half cycles = 1 full cycle (and similar for smaller values). However, that is only a rough approximation, in reality, the shallow cycle will be better than the equivalent full cycle.

Also, if Tesla's thermal management system is like most, it'll be using set points and the operation modes when stationary (and not in drive) and when driving are likely very different.

 

[AnxietyRanger]

Here are summaries of some of the findings so far. I agree it seems at this stage, beyond some 200-300 DC charges and especially 90 kWh (but some others) batteries, seem to get Supercharging peak rate throttled.

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

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

 

[AnxietyRanger]

I don't follow your logic. I know upgraded packs in 2015 were 90 packs. So we know those packs have cells that contain silicone. Saying Tesla told us the 100's use the same cells at the 90's means nothing since all Tesla vehicles to date use the Panasonic 18650 cells, but inside some of them have silicone with the graphite, and some have only graphite. So saying they use the same cells is very different from using the same chemistry. We know from Elon that this was an experiment and Tesla was using "baby steps" with silicone. There was a good reason for baby steps, since they wanted to see the results, and after doing so, Tesla may have walked back those baby steps.

Pictures of the modules mean nothing. It's the chemistry inside the cells that needs to be analysed and wk057 did not do that.

It is scary agreeing with @Canuck all the time, I fear for the balance in the force, however once again I must.

I think his speculation/analysis on the silicon in anodes is solid. We do not know how the silicon experiment in the batteries progressed, all we know is that around the 90 kWh introduction Tesla started testing it and that there have been more info on increased degradation (separate from this thread) and peak rate throttling (this thread) on 90 kWh packs than others.

What it all means and how it went from there, we don't know yet...

 

[AnxietyRanger]

I just want to add, it's not the throttling that irks me. It's the fact that Tesla hid the fact that DC Fast Charging causes degradation and that they will permanently throttle your charging rate if you do it.

Couple that with the low ceiling of < 300 DC Fast charges, and you are basically selling a car that WILL get throttled at some point in its life. If that information had been communicated from the start, that's an entirely different discussion.

This here is the beef. This needed to be disclosed and needs to be disclosed better in the future. Owners need to have information on relevant factors that affact their battery longevity. That's why there is the 80-90% rule and now we need guidance on the DC charging effects as well.

At this time it seems to be avoiding unnecessary DC charging seems to be warranted advice, especially on 90 kWh Teslas.

 

[whttiger25]

Can reduced supercharging be a warranty claim in itself? You paid for a car capable of 120KW charging, suddenly it can only do 75% of that. Should it be considered broken? It is a part of the drivetrain+battery system. Tesla charges $1,900 for charger upgrade from 48A to 72A, so charging capabilities obviously have monetary value (at that rate the 30KW reduction should be worth roughly $10K).

Nope. It covers malfunctioning or defective battery. You'll need an extreme case and either a lawyer or goodwill from tesla to get anywhere if the battery is charging and discharging without issue. No guarantees were ever made about the rate at which the battery could be charged. You can search the fine print and marketing, tesla has been careful. To me range loss from gradual degradation is a more serious issue than charging at 90kw vs 120kw, and that is explicitly not covered. Plus, don't think you can extrapolate value of the 72A charger, I'd argue the value curve there is quite logarithmic, and most people wouldn't voluntarily pay for the 72A charger because the value actually isn't there.

Here are some quotes from the Tesla supercharging page showing how they are protecting themselves.

"...to deliver up to 120kw of power"
"The car's onboard computer constantly monitors the battery during both driving and charging to ensure that it maintains peak performance"
"There are many factors that affect the actual charge rate,...., amongst others."
"Actual charge times may vary"
"...provide up to 170 miles of range in as little as 30 minutes"

I feel like Tesla should have been more upfront about this, however, I understand the laws of physics and for me capacity preservation over the long term is the most important factor. I don't think it's in teslas best interest to slow down supercharging for any reason other than battery protection, especially with the shift towards a payment model for supercharger electricy. That actually incentivizes them to keep charging as fast as possible, as it would result in a faster payback period on fewer required chargers/smaller required capital investment. Because of their desire to protect our batteries they will be forced to build more suoerchargers. I can't say they are only bring generous - they are probably also protecting themselves from battery failures and warranty claims.

 

[Ulmo]

My 75 has always been the same. About 92, max ever about 98.

Of many times I SuperCharged my 60D/75D, only 3 sessions hit 100kW; the rest went up to about 98kW. I believe 98kW is higher in the bell curve average for what the equipment can deliver, but some SuperChargers are slightly less normally tuned and put out a bit more.

Hey have you noticed that when you plug in at a SpC, it may say 50 minutes remaining, but when you leave for 30 minutes and come back, it doesn't say 20 minutes, it says 30 minutes remaining? I've noticed that the time is not accurate, and it ALWAYS takes longer than the estimated time. Could the time be based on some "ideal" rate, and not taking into account the actual charge rate?

I sometimes get that, and I sometimes get it going faster than quoted.

 

[AnxietyRanger]

Did they hide this fact, or did they just learn it themselves after adding silicone and seeing the results?

I think we should be careful attributing nefarious conduct when there are other just as plausible explanations.

What irks me is Tesla not telling us exactly what triggers a vehicle to join the 1%'ers.

We have Service Center reports of Tesla knowing about this issue for weeks or months now, at the very least. They could have made public disclosure, updated FAQs, manuals or somesuch, but no. Still their Supercharging FAQ for example only says this. One of the first places they would IMO have rushed to update if yesterday after the weekend they noticed this terrible omission in their guidance...

I am not Supercharging as quickly as I expected. What could be happening?
Your vehicle and the Superchargers communicate to select the appropriate charging rate for your car. Supercharging rate may vary due to battery charge level, current use of the Supercharger station and extreme climate conditions. Your vehicle charges faster when the battery is at a lower state of charge and charging slows down as it fills up. Depending on your destination, charging to completely full is often not necessary.

How can I maximize power and reduce charge time at a Supercharger?
Each charge post is labeled with a number and letter, either A or B (e.g. 1A, 1B, 2A, 2B). When possible, select a charge post with a unique number that is not currently connected to a vehicle. When a unique number isn’t available, the Supercharger cabinet has technology to share available power between charge posts A and B. To maximize power, park at a Supercharger shared with a car that is nearly done charging.

I would say it seems likely Tesla is intentionally not disclosing this so far beyond where absolutely impossible to avoid (e.g. service, this forum). After the publicity, they may have to change that tactic, though. Or maybe they will try to continue flying under the radar.

 

[AnxietyRanger]

I agree it would be nice for Tesla to be more transparent. But considering my wife and I have over 150,000 miles on Tesla vehicles and have used SCs with most of them, and have experienced no throttling, I have no anxiety over this.

Would you be willing to report on your Model X 90D roughly:

1) Total miles on the X
2) Total percentage Supercharged/CHAdeMO (vs. other) on the X
3) Peak Supercharging kW currently on the X

The X would give very little data.
It is less than a year old, has under 10,000 miles and is rarely SC'd.

Our Sig S had much more history, but of course, it didn't have the newer batteries.

Thank you very much, @Zythryn.

I think this helps place your information on the "85 kWh's are not the main issue here" bracket.

90 kWh seems to be where the biggest problem is at so far...

 

[Evoforce]

It is scary agreeing with @Canuck all the time, I fear for the balance in the force, however once again I must.

I think his speculation/analysis on the silicone in anodes is solid. We do not know how the silicone experiment in the batteries progressed, all we know is that around the 90 kWh introduction Tesla started testing it and that there have been more info on increased degradation (separate from this thread) and peak rate throttling (this thread) on 90 kWh packs than others.

What it all means and how it went from there, we don't know yet...

This harkens back to many past/present conversations and debates on the mynissanleaf.com forum posts.

 

[AnxietyRanger]

This isn't the first time or first issue where we have heard non-transparent, misleading, vague responses from Tesla. The 694 HP issue, 2015 90D's rapid range loss, Josh Brown NHTSA incident, AP1 and 2 persistant problems, the Model X rollout, and "countergate" are all examples of this. They really need to get their act together before the M3 comes out. Who else but us would put up with this stuff?
I think people would feel better with honest, straightforward communication than what we have seen lately.

This is the reason why I feel Tesla is increasingly getting the heat or at least disappointed looks from the enthusiasts. The list just keeps growing.

This seems cultural at Tesla. They can't seem to keep it on the straight and narrow when it comes to public disclosures.

 

[AnxietyRanger]

I won't change anything, but I'm not someone who almost exclusively charges with CHAdeMO or Superchargers. I absolutely understand that those who require those types of chargers on daily commutes have valid concerns.

Pending further information or diclosures that would make me thing otherwise, personally I will avoid all unnecessary DC charges from this point onwards and recommend everyone to do the same.

Use your car, but if you can AC instead of DC, do that. Seems like the educated choice at this stage. Similar to 80-90% - and 100% only when you have to.

 

[AnxietyRanger]

And to me, the "less than 1%" number just means how many people have this particular style of charging usage. If it's a ratio, if it's a count, if it's a "time spent above X".. who knows. But I think that's where the (less than) 1% number comes from. My guess.

It could be both driving style and battery type, though.

What it isn't, is IMO clear, a plain defect percentage - i.e. less than 1% of Teslas have this fault/feature. No, it includes an active element (e.g. how you charge) and that's why it would be very important to know who are in the risk group of becoming less than 1%enters.

The less than 1% is not just your lottery odds. This is more like poker, how you play matters. We just don't know all the rules of the game yet.

 

[Ulmo]

Hi Everyone -

The peak charging rate possible in a lithium-ion cell will slightly decline after a very large number of high-rate charging sessions. This is due to physical and chemical changes inside of the cells.

Our fast-charge control technology is designed to keep the battery safe and to preserve the maximum amount of cell capacity (range capability) in all conditions. To maintain safety and retain maximum range, we need to slow down the charge rate when the cells are too cold, when the state of charge is nearly full, and also when the conditions of the cell change gradually with age and usage.

This change due to age and usage may increase total Supercharge time by about 5 minutes and less than 1% of our customers experience this.

Tesla is not slowing down charge rates to discourage frequent Supercharging – quite the opposite. We encourage our customers to use the Supercharger network at their discretion and we committed to doubling the number of worldwide chargers just this year.

We also want to ensure that our customers have the best experience at those Superchargers and preserve as much vehicle range as possible even after frequent usage.

Thanks,

Jon

Thank you for this information.

How does this relate to Chademo charging, and should I refrain from using Chademo as much as possible, even at the expense of arriving at home with under 20%, 15%, 10% or 5% state of charge?