Wiki Sudden Loss Of Range With 2019.16.x Software

[Guy V]

There is, @wk057. Too bad the self appointed thread police and a 20 post newbie (who didn't know his technical chops and posting history) drove him off. Since then, there's been a few questions his already answered elsewhere (pack rebuilding/cell matching).

Not really. What he does say generally is always interesting but when the questions approach the core issues of this thread he clams up.

 

[Guy V]

All packs use cells in parallel. A cell is made up of layers in parallel. Closely matched cells should have minimal drift.

So if this really our problem Tesla had quality-control matching issues which they should be responsible for rectifying, right?

 

[tga]

Not really. What he does say generally is always interesting but when the questions approach the core issues of this thread he clams up.

Puh-leeze... He's had thousands of posts and years of contributions to this forum (and elsewhere) that clearly establish that he's earned his self-declared title of "Senior Tinkerer." He doesn't need to, and shouldn't, waste his time with call-outs from you, me, random newbies, or this thread's self-appointed thread police.

If he says he can't go into any more detail for fear of legal retribution, that's good enough for me. It should be good enough for anyone else here, too. If it's not, tough.

 

[gmo43]

I lied. I came back one more time to do this. Maybe now I can tolerate reading this again.

View attachment 565966

All of you blocking each other. Grow up! Take everyones view like an adult. If you dont like it move on and read the next post. There are plenty of people I disagree or dont like what they say but never block because I disagree. But again its everyone right to do whatever, just dont be all look how cool and funny I am. (not really) by blocking people. When people are actually having issues with their cars and this company.

Edit: I believe he/she also said such thing and also needs to put his big persons pants on lol

 

[Battpower]

The experience of my entire life is that batteries never last forever and that I have a personal aura that accelerates their death.

I bought a Tesla after an eye-opening test drive and serious consideration of the downside risk. My first overriding concern at the time, in spite of the above wasn't how long the battery would last, but how long Tesla itself would last which was very questionable. Of course then my risk concern turned to how well and how long the car would hold up and continue to perform. So far we've gotten well past those issues and I have loved my P85 which amazingly still looks and drives almost like new.

Then to the battery life issue, which is my own personal bugaboo. I decided based on Elon's 8-year warranty, as exuberant as the car itself. My logic was that if the company was intended to survive long-term they must have some substantial basis for confidence the battery pack would hold up, or at least a practical plan to manage refurbishing/replacing it.

It's been a good run and I am STILL holding on to shreds of Elon-scale optimism that it can work out, and have my $100 down for a Cybertruck, but I do wish they would get on with fixing this.

So far my battery experiences with Ev's and home storage is pretty good in so much as they at least live up to the warranty. Having the stored up liability of eventually needing to replace batteries is still not really appreciated by the marketplace - reasonably.

 

[Battpower]

He doesn't need to, and shouldn't, waste his time with call-outs from you, me, random newbies,

Yes.

No harm reminding him that his opinion is valued and experience recognized. It does take an immense amount of time to read up on the back story and history of everything on TMC and to get a clear picture of who knows what.

 

[Battpower]

So if this really our problem Tesla had quality-control matching issues which they should be responsible for rectifying, right?

I don't think it is established there were (or are) matching issues. It is just speculation. Less speculative imo is that

1) Parallel connected lithium cells must be accurately matched especially in demanding applications.

2) It is not easy to accurately determine what is going on between individual parallel wired cells within a brick other than making assumptions based on what happens to the voltage and temperature of the brick under load / charging.

3) Most components (in general) are more likely to deviate from their original specs over time when used in harsh conditions.

 

[tga]

View attachment 565772 View attachment 565774

These SMT screenshots are from my Raven LR.

The 15mv imbalance in brick voltage was after the car had been sitting unused for a few weeks.

After a few long slow charging sessions at around 2kw, the cells balanced to within 4mV, and the majority are + / - 1mV.

The only possible relevance of this is that I believe batteries balance during charging and that when sitting idle, bricks can drift out of balance. If this behavior is evident in a newish low mile car, then likely to be more evident in some older cars where cells have undergone longer aging.

I've seen similar behavior in my P85+. Prior to Covid-19, my daily charge was 70%, but I went to 90% once a week or so for a long drive. I was seeing imbalances of ~4mV. Post-covid, I did little driving, started lowering my charge level to 50%, and saw a 14-15mV imbalance develop. Now that I'm back to my old charging habits and driving more, I'm down to ~9mV. My typical AC charge is 20-24A.

 

[Battpower]

I've seen similar behavior in my P85+. Prior to Covid-19, my daily charge was 70%, but I went to 90% once a week or so for a long drive. I was seeing imbalances of ~4mV. Post-covid, I did little driving, started lowering my charge level to 50%, and saw a 14-15mV imbalance develop. Now that I'm back to my old charging habits and driving more, I'm down to ~9mV. My typical AC charge is 20-24A.

Is that at 110v or 220v? I believe it is more a question of what power is going into the battery and over how long. I always check the power meter on the AC supply to make sure of the power. I'm sure that any AC charging rate is going to be pretty gentle on the battery, but I do think keeping the battery on charge for long periods at necessarily low power is good for cell balance.

 

[Chaserr]

Realizing it's heading way off topic, though relevant to how we weigh and compare the various attempts at using science based data, real evidence, and reasonable conjecture to understand the subject at hand, there are some key factors the quoted article misses on why people disagree on science.

Science is not equal to truth. There are many atrocious examples of peer reviewed, widely accepted, scientific "facts" that later turned out to be categorically untrue. With modern communication the general public is now more easily kept informed of the ever changing reality established by science. Many of these false sciences were widely accepted in the common manner of group think. It isn't just absurdly false science like a flat earth or 100 MPG carburetor that causes people to distrust science based conclusions.

Another ignored fact is that scientific conclusions come from humans and humans are biased. This means scientific conclusions are influenced by bias, sometimes political. Politically biased conclusions are rapidly picked up by those with similar bias and used to support their position. It's also not all about peer reviewed science. There are "scientists" on both sides of whether to physically send children to school this fall. The ones who conclude they should stay home get invited onto CNN and the ones who conclude they should be in school appear on Fox. Neither of them really knows what the results will be, because science can't predict the future.

Hydroxychloroquine anyone?

Well said. What's important is choosing scientific method of reason instead of unreasonable denial based on hate or bias. Hydrochliroquine us a great example because it was rejected by politically biased people, all the while it's decades of medical evidence suppressed in favor of a predetermined conclusion that was based on lies. Eventually, scientific reason won but biased vitriol worked very hard to suppress evidence without supplying any.

Reason is all that matters. Rejecting reason is a serious problem and it's who people work so hard to deny evidence they can't stomach.

 

[Battpower]

Regarding supercaps, yes, awesome way of delivering and absorbing bursts of full power / regen regardless of battery SOC, so super useful at reducing stress on battery.

Capacitors never make sense in an EV. The cost, volume, and weight are always better used to put in more cells and giving you a larger pack. The "answer" to all the problems is more durable cell chemistry and increased energy density, which is where we are headed. .......

So I think more durable cell chemistry obviously makes sense. But capacitors are so 'mechanical' in their nature as well as intrinsically able to soak up punishment that is hard for 'chemistry' to match. Of course its always about limits and comprises.

It feels like super / ultra caps have been on the cusp of mainstream for a while... (long time) without making it.

I just found this fairly recent paper that sets out some info relating to vehicle applications.

Still digging to see if I can find latest on highest energy storage vs size & weight.

https://www.researchgate.net/public...hicles/link/57a4d73b08aefe6167b05355/download

From an earlier document (2000) just to show some parameters:

Energy isn't so important for the cap anyway since that's the battery's job. Max power for just 5 seconds is quite useable when you are looking at 0-60 in 2.5.

Of course, all down to size and weight with enough energy to be worthwhile.

 

[tga]

Is that at 110v or 220v? I believe it is more a question of what power is going into the battery and over how long. I always check the power meter on the AC supply to make sure of the power. I'm sure that any AC charging rate is going to be pretty gentle on the battery, but I do think keeping the battery on charge for long periods at necessarily low power is good for cell balance.

240V, so 5-6kW. They only time I've used the UMC's 120V adapter was to check the idle current of the UMC. I don't think I've ever fed the car with120V; I've definitely charged more often at 277V than 120V.

 

[tga]

Hydrochliroquine us a great example because it was rejected by politically biased people, all the while it's decades of medical evidence suppressed in favor of a predetermined conclusion that was based on lies.

"Decades of medical evidence" treating a virus that didn't exist a year ago. Yeah, right.

 

[Chaserr]

It's been used effectively for longer than you know and yes longer than SARS existed. It's why we know it was at least promising as as a potential effective early management fir this specific virus, people taking it for years that have been exposed were studied and now it and other similar arthritis medications are being studied for promising concrete results already observed by patients already on it for years.

This drug is a good example because it was used by politically biased pundits to try and make an old well studied drug sound dangerous and new. Science never rejected it but a lot of biased people didn't want it studied.

 

[Guy V]

Puh-leeze... He's had thousands of posts and years of contributions to this forum (and elsewhere) that clearly establish that he's earned his self-declared title of "Senior Tinkerer." He doesn't need to, and shouldn't, waste his time with call-outs from you, me, random newbies, or this thread's self-appointed thread police.

If he says he can't go into any more detail for fear of legal retribution, that's good enough for me. It should be good enough for anyone else here, too. If it's not, tough.

But none of that is the point is it? He will not answer questions about this problem, which is what the poster you responded to asked for.

He will for his own reasons not tell us what he knows about it so it is useless for you to suggest him as a resource.

We can all stop bothering him about it, right?

Do you have something helpful to contribute, like someone who will provide answers?

 

[Guy V]

So far my battery experiences with Ev's and home storage is pretty good in so much as they at least live up to the warranty. Having the stored up liability of eventually needing to replace batteries is still not really appreciated by the marketplace - reasonably.

We are really ticking down to the ends of 8-year warranties when notice will start to be taken of what comes after.

Auto companies with good reputations didn't get them by building cars that only last 8 years.

 

[Chaserr]

That is exactly the point. This discussion is held by people accept authority over evidence, and by people who accept evidence over authority. Two schools of thought.

It would help if those claiming authority could back their statements with with maybe a shred of evidence and they have refused. In several instances, evidence proves authority should not be believed because we've seen them make claims we can use evidence and deductive reasoning to show are factually untrue. Authority can say anything, and it will be believed by anyone who chooses to believe.

The other school of thought - evidence - can change everyone elses minds . Evidence can erase previous hypothesis instantly, as long as we are able to accept the evidence and try to reason through it.

 

[Chaserr]

Your ticking down comment gave me a chilling thought. Tesla has every cars birthday built in. They can kill them all at 8 years if they want to stop unlimited supercharging it sell more batteries.

Will they? Adverb not, but does anyone trust them not to consider it?

In my opinion battery day must be planning a battery refreshment program for older cars. Disposable teslas isn't just bad for sales now, disposable cars kills teslas mission and is bad for their reputation firever. There's nothing sustainable about disposable cars they don't want anyone to fix.

 

[Battpower]

We are really ticking down to the ends of 8-year warranties when notice will start to be taken of what comes after.

Auto companies with good reputations didn't get them by building cars that only last 8 years.

Absolutely.

And while we all love the lower fuel costs, 20k worth of replacement battery for say a 10 year old car will make the car worth about.........?!

Clearly there needs to be shift in how this works. In Europe, Renault tried renting their batteries to owners with replacement included if the battery fell below 75% iirc. Needless to say the costs seemed stacked against the owner and really took the shine off EV ownership imo.

All kinds of problems like who owns the car if the battery gets written off. Can insurers salvage the battery if the car is a write off? Who pays rental while used cars sit on dealership lots?

Which is why I see the attraction in babying the battery and trying to get maximum life from it.

 

[Battpower]

Evidence can erase previous hypothesis instantly, as long as we are able to accept the evidence and try to reason through it.

Yes!

Give me evidence! Enough hypothesizing.