Pack Performance and Launch Mode Limits

[Walta]

I don't think Tesla has all the data, because:
1) They can't reasonably force the car into the cycle that would trigger power limitations (AKA 100% SOC, max battery). That would have to be something owner initiated.
2) They aren't saving continuous power data with enough granularity to show voltage and current, remotely (via their servers) or locally (saved in car for service to retrieve), so even if a owner does trigger that, they won't have the data.

Of course #2 may change with future updates (they can make a update that remotely or locally gets the targeted data), but #1 would not.

I am figuring #1 will just happen anyhow with owners. Since I expect most of the ludicrous owners, would tend to use the car in a ludicrous enjoyable manner.

 

[stopcrazypp]

But wouldn't it be more useful to collect that data in public? An Excel similar to the VIN and update ones?

What use is sharing data to Tesla who already knows what is happening. The community does not know.

I'm not saying the data gathered has to be kept private, just that there is a private thread for the data gatherers to post in. There can be a separate public thread (or just right here) that discusses the data.

The idea would be to keep the speculation separate from the data. There's been plenty of threads on this forum where 90% of it is noise, while less than 10% of it is actual data. This makes it extremely hard to separate what is speculation and keep track of everything. I'm certainly guilty of contributing to that noise, but that's just the nature of public discussions.

 

[AnxietyRanger]

I'm not saying the data gathered has to be kept private, just that there is a private thread for the data gatherers to post in. There can be a separate public thread (or just right here) that discusses the data.

The idea would be to keep the speculation separate from the data. There's been plenty of threads on this forum where 90% of it is noise, while less than 10% of it is actual data. This makes it extremely hard to separate what is speculation and keep track of everything. I'm certainly guilty of contributing to that noise, but that's just the nature of public discussions.

That is easy to agree with. No disagreement there. Thanks for clarifying.

I guess this is one of those cases where a lot of people talk past each other a bit. Some are advocating keeping things private, while some are only advocating clarity and many things in between.

 

[hostman]

And how many Launch Mode and WOT events during those 20 years and 300k miles?

Let's say the avg projected is
X LM events per 20 yrs/300k miles,
and
Y WOT events per 20/300

And let's say in their testing the powertrain perfectly handles 2X LM and 2Y WOTs.

And what if someone does 4X LMs and 5Y WOTs in the first 6 mos of ownership? And it was 4X and 5Y that triggered a limit.

That's all that is meant by no design is for unlimited use. And still ignorant of those numbers above you cannot conclude that anything was under designed.

The point is that under severe duty, if the failure mode is catastrophic, the longevity must be great. That's all I'm saying.

 

[hostman]

Duty-cycle-based parts replacement has been the norm for many industrial products for more than 100 years. Tolerances have drawn tighter as better metrics, more precise and accurate measurement have become available.
I am not an electrical engineer nor an engineer at all. I have operated and owned a fair number of highly complex industrial products that had life-cycle fixed replacement and/or inspection based on time and/or usage conditions and/or duty cycles. I admit I am making yet another aviation analogy.

For such issues as Ludricous Launch and Takata airbags, duty cycles and/or time and/or operating conditions determine replacement, maintenance and/or inspection.
That is just the way it ought to be.

Not really. We are talking about fairly reasonable power increases. They very slightly under-designed the car. Total cost difference to fix? Probably up-front we'd be talking about $10-20. At this point? $20k+.

 

[hostman]

There's not a lot of difference between 1300, 1500 and 1600. Engineering of mechanical systems is simply not so precise that you can say that it's good for one and not the other. You will have variations in materials, manufacturing tolerances, heat treating processes and various other factors that mean that failures are going to follow a statistical curve. And of course you have variations in the way that people use the product.

The only way to assure no failures is to add a large overdesign factor. And that leads to a heavier product and poor performance.

It's incredibly tough to find the right balance. And it takes a lot of vehicles in the field running in real-world conditions. And there WILL be some issues.

Actually, you've missed a few points. One is that V = IR. P = IV. Therefore, P = I^2 R. So running at 1600A = 52% more heating than at 1300A. So yes, electrical systems are so precise. I know mechanical engineers have way larger tolerances to work with, mainly because they have to BS their load cases.

I think it's obvious that Tesla had this fully dialed-in at 1300A, downgraded some parts to be cost-efficient at that level, and then forgot about all the little pieces when they tried to increase power.

 

[hostman]

The above is not quite accurate, and I think it is important to make this distinction.

We don't know of any cars that reached the limit of the weakness and broke down or needed maintenance of some kind. We don't know what the real limit, in that sense, is.

We do know that several cars were preemptively power-limited by the counters, which presumably was done to protect them from actually reaching the point where they would break down or require warranty service. One (or more) may have reached the counter limit in three months, but none actually broke down or required service in that time period, at least as far as we know. (I'm not including the need for service due to the counters being reached, of course.)

I just wanted to point out that, in my opinion important, distinction.

Agreed 100%. None of these cars was malfunctioning when v8 came out and limited them.

 

[hostman]

I agree. Maybe I was unclear, the context was key though. I did not mean to suggest the cars reached the physical fault but that they reached the end of the Performance duty cycle - in this case represented by application of limiters.

A duty cycle made up ex post facto when Tesla realized their screw-up.

 

[AnxietyRanger]

A duty cycle made up ex post facto when Tesla realized their screw-up.

Yes. But again context is key here, my message was in response to a comment about duty cycles being normal.

Myt point was this particular "duty cycle" (the counter/limiter duty cycle) was unplanned, unannounced, unreasonably short and abnormal in the sense that there was no maintenance regime or fix offered...

Agreed 100%. None of these cars was malfunctioning when v8 came out and limited them.

Obviously agreed. The duty cycle I referred to was the invoking of the limiters, thus ending the Performance/Ludicrous "duty cycle" in a non-fixable manner (until now, the difference now is there is a fix and it is covered by warranty).

 

[hostman]

Yes. But again context is key here, my message was in response to a comment about duty cycles being normal.

Myt point was this particular "duty cycle" (the counter/limiter duty cycle) was unplanned, unannounced, unreasonably short and abnormal in the sense that there was no maintenance regime or fix offered...



Obviously agreed. The duty cycle I referred to was the invoking of the limiters, thus ending the Performance/Ludicrous "duty cycle" in a non-fixable manner (until now, the difference now is there is a fix and it is covered by warranty).

I think we are in complete agreement then.

 

[AWDtsla]

Duty cycle was not decreased. Duty cycle is the wrong word.

Peak current was decreased in response to components that should effectively have an infinite cycle life having a very very finite one. In general if you have passive components that fail under cycling you've made an engineering error. Ever hear of the wires in someone's house just "wearing out" and requiring replacement? No, they are passive components, they should outlive the house they are in.

If your M3 revs to 8000 RPM, and then BMW discovers that because of an under-engineered component these engines eventually blow up, then they push a software update to limit to 7000 RPM to prevent that, they have not modified the "duty cycle", they've altogether limited output. Of course the latter part did not happen, but they did blow up hundreds of customer's engines, through no fault of the customers.

 

[brianman]

@lolachampcar
As previously noted, I support your proposal and hope it gets some legs. Unfortunately, I'm not optimistic.

I've talked to a number of Tesla employees and some that have worked with Tesla (some of the sponsors attending TMC Connect, for example). The universal impression I've gotten is "if you talk about performance / track experience" it's (to put it politely) "a career limiting move" -- directly from Elon. The underlying thought being "3 is the priority, performance efforts is just a distraction".

I find this view confusing, given that Elon (and perhaps others) at Tesla are clearly obsessed with the Performance side of things -- and see it as important to the overall mission. If he didn't view it as important to the mission, then Elon would be stupid to waste time and introduce risk (repeatedly!) to push the performance side of these vehicles.

We know (well, "I strongly feel") that Elon is not stupid -- but I definitely have found the cognitive dissonance frustrating since 2012.

I socialize with track enthusiasts at least monthly and wish Tesla would "take this enthusiast community seriously" like Audi does. There's no downside AFAIK and tremendous upside opportunity.

@JonMc - Any chance you're listening?

 

[AnxietyRanger]

My duty cycle response (it was a response to another one's duty cycle comparison) is like a joke that has been explained six times too many. I give up.

Pack Performance and Launch Mode Limits

 

[AnxietyRanger]

@lolachampcar
As previously noted, I support your proposal and hope it gets some legs. Unfortunately, I'm not optimistic.

I've talked to a number of Tesla employees and some that have worked with Tesla (some of the sponsors attending TMC Connect, for example). The universal impression I've gotten is "if you talk about performance / track experience" it's (to put it politely) "a career limiting move" -- directly from Elon. The underlying thought being "3 is the priority, performance efforts is just a distraction".

I find this view confusing, given that Elon (and perhaps others) at Tesla are clearly obsessed with the Performance side of things -- and see it as important to the overall mission. If he didn't view it as important to the mission, then Elon would be stupid to waste time and introduce risk (repeatedly!) to push the performance side of these vehicles.

We know (well, "I strongly feel") that Elon is not stupid -- but I definitely have found the cognitive dissonance frustrating since 2012.

I socialize with track enthusiasts at least monthly and wish Tesla would "take this enthusiast community seriously" like Audi does. There's no downside AFAIK and tremendous upside opportunity.

@JonMc - Any chance you're listening?

Not that I know anything about their internal thinking, but going by the public info I don't find it at all hard to reconcile those two different points of view.

Elon wanting Performance headlines for PR gain and next quarter demand lever can certainly be completely separate from a serious track and performance effort.

One is a trick, the other is a commitment. I think the Countergate story is really proof positive Tesla has been a bit more about the former than about the latter when it comes to Performance.

 

[Peteybabes]

Oooo wish list time

Centre rear arm rest, grab handles, string between the parcel shelf and the trunk, knee support on the front seats... this could be fun

bring back executive seating. (with rear entertainment options and possibly a fridge) massage on some seats, and also cooling in the rear seats. my biggest wish is a LWB version of the MS! (or at least a bigger car)

 

[AnxietyRanger]

bring back executive seating. (with rear entertainment options and possibly a fridge) massage on some seats, and also cooling in the rear seats. my biggest wish is a LWB version of the MS! (or at least a bigger car)

Hear, hear.

My duty cycle shortens considerably without those amenities. Or does it get longer? I forget.

 

[lolachampcar]

Wow....
I was not talking about power numbers or related data. I believe Tesla's heuristics are designed to tell them where the battery system is in its lifespan. They do not need anything from me on that subject.

I was more interested about having the "what do we do now?" conversation. Hey owners, the 100DL battery fixes what we know about but we do not know what we do not know so we can not guarantee the P100 battery will not have another issue (the the web site disclaimer which could only apply to the P100D(L)). Do you V3 folks want one for $20K and 85DL for $30K? Cost sensitivity. Reaction to potential hard failures. Tesla will ultimately interact with us in the future at some point when things fail (at least some, we really do not know how many and when because we do not know the end game failures that drove the need for counter limits) so why not talk with us now as a group and gage our willingness to go along with different options (like the battery buy suggested earlier). That is what I meant by being part of the solution.

 

[P85DEE]

I'm not saying the data gathered has to be kept private, just that there is a private thread for the data gatherers to post in. There can be a separate public thread (or just right here) that discusses the data.

This is a very reasonable approach.

I tend to believe and strongly, that the best place for public discussion on this matter is on this forum.

The idea would be to keep the speculation separate from the data

Nothing wrong with speculation and opinion. But you're right, there should be a de facto place for it.

There's been plenty of threads on this forum where 90% of it is noise, while less than 10% of it is actual data. This makes it extremely hard to separate what is speculation and keep track of everything. I'm certainly guilty of contributing to that noise, but that's just the nature of public discussions.

And always will be. And the "noise" is of many varieties.

Some of it actually valuable and constructive noise, such as many times the case with my own.

But then it can get to destructive and mean spirited noise.

And worse case anti Tesla noise.

And if the wrong type of "participants" enter into the discussion, "short selling" and anti EV type noise.

It's those latter variants which should be avoided at all costs.

 

[Walta]

AR,
It's my hypothesis that there is an underlying issue identified in life cycle testing. If I am correct, I would like to work as a group of owners directly with Tesla to understand and help address the issue(s). I personally would do it inside a private chat or email chain so exact details can be discussed as well as hashing out the pros and cons of any possible solutions. IMO, discretion is needed when discussing sensitive topics and only stakeholders really need to participate.

I have this strong desire to be part of the solution as well as part of pointing out the problem. IF, and that is a very big if, there is an issue that might drive battery failure, I'd like to quietly work with Tesla to prevent it from happening. It is in everyone's best interest to do so.

@lolachampcar
This sounded like you wanted to find the root cause, and apply a fix? I totally misunderstood...

I can see the clear benefit of working with Tesla to come up with options on how they handle the eventual warranty claims.

 

[msnow]

@lolachampcar
This sounded like you wanted to find the root cause, and apply a fix? I totally misunderstood...

I can see the clear benefit of working with Tesla to come up with options on how they handle the eventual warranty claims.

You're not the only one, I thought they wanted to help find the cause also.