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Sorry, you have all been played. GM won't be replacing jack because they don't even have the ability to make a safe battery pack. No way they are going to tie up multiple factories for a year or more to help existing customers. That's never been the GM way. This won't get resolved until state attorney generals and/or the Feds step in and force their hand. That's what all of this stalling is about.
Good ole troll firebolt. Isn't this the same guy that refuses to believe Texas could possibly have a decent lemon law, even after he was presented with evidence to the contrary? Please stop trying to rile people up with your nonsense.

 

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Sorry, you have all been played. GM won't be replacing jack because they don't even have the ability to make a safe battery pack. No way they are going to tie up multiple factories for a year or more to help existing customers. That's never been the GM way. This won't get resolved until state attorney generals and/or the Feds step in and force their hand. That's what all of this stalling is about.
OH NO,,,,
Buddy, what do you recommend we do until then? :unsure:

Please! We need some impartial advice!

umm, LG makes the cells.
For many EV manufactures.
Tesla does not make their own little cells either.
 

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Much has been made of whether EV cells are pouches (e.g. LG) or something else (e.g. Tesla). I won't pretend to understand the significance of that, but while it may be true that Tesla doesn't make their own cells either, one must admit that Tesla have at least found a supplier whose cells don't spontaneously erupt into flames the way some of LG's cells apparently do (at least, not anymore, haha). Between the recent fire in a VW ID.3 in the Netherlands, the Hyundai Kona fires, and the Bolt fires, all with cars using cells from LG, it's pretty clear which company I don't want making battery cells for my car, at least not right now. We've a GM case number for a buyback and have provided them with the requisite paperwork, so now we're just waiting for them to do the math, ask us whether we want to accept the offer, and tell us when to pick up the check. We'd love to have them replace all the battery modules in our Bolt with known good ones because we love the car, but given this is our second Bolt recall for the same problem and a fix may take longer than we're willing to wait... (Yeah, we had a 2019 which they bought back and we used that to buy a 2021 - but now that one's recalled too.)
 

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Much has been made of whether EV cells are pouches (e.g. LG) or something else (e.g. Tesla). I won't pretend to understand the significance of that, but while it may be true that Tesla doesn't make their own cells either, one must admit that Tesla have at least found a supplier whose cells don't spontaneously erupt into flames the way some of LG's cells apparently do (at least, not anymore, haha). Between the recent fire in a VW ID.3 in the Netherlands, the Hyundai Kona fires, and the Bolt fires, all with cars using cells from LG, it's pretty clear which company I don't want making battery cells for my car, at least not right now. We've a GM case number for a buyback and have provided them with the requisite paperwork, so now we're just waiting for them to do the math, ask us whether we want to accept the offer, and tell us when to pick up the check. We'd love to have them replace all the battery modules in our Bolt with known good ones because we love the car, but given this is our second Bolt recall for the same problem and a fix may take longer than we're willing to wait... (Yeah, we had a 2019 which they bought back and we used that to buy a 2021 - but now that one's recalled too.)
To back up what you are saying, I will share my early Tesla experience. The details can be read at: Dead Battery (post#10)

In summary, I have a 2012 Tesla Model S which left me stranded without warning due to a battery module failure. Tesla replaced my battery and didn’t give me anymore information. Looking back, I wish I had asked more questions. I was just excited to get a new battery with more range. I suspect my battery module experienced either a short or open condition.
My point is- there was no fire. Either by module design or software, my battery experienced sudden loss of range due to a module failure without a fire.

GM needs to design a fail-safe for cell failure. I don’t see anything from them about this being built into their Bolt battery or their new Ultium battery.

I appreciate trying to achieve low cost EVs, but not at the cost of putting our families at risk of fire!
 

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I have a 2012 Tesla Model S which left me stranded without warning due to a battery module failure. Tesla replaced my battery and didn’t give me anymore information.
That is nothing. Lots of Bolts did that when they first came out. We got two software fixes for that one. One EV journalist had his battery replaced three times! :p
 

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My point is- there was no fire. Either by module design or software, my battery experienced sudden loss of range due to a module failure without a fire.
As pointed out, there have been Bolt battery issues that have had the same result.

The question is, if Tesla had a situation where there were defects in their cells that would result in thermal runaway, would their pack design keep that cell from affecting neighboring cells enough to prevent this issue.

It is a good question...

There is the fact that there is some extra spacing, with the cells being cylindrical.
There is also the fact that each cell is much smaller... Smaller means less heat released if it goes thermal...

I can see how that could make a difference, but I don't know how much heat a single Tesla cylindrical cell in runaway produces, and what would be the actual effect on neighboring batteries.

It is good we haven't seen Tesla fires as a result of this type of thing. But is that a result of the design or just that their quality control has been better?

I honestly don't know. The design does seem better at possibly addressing that, unless even a single cell in runaway could produce enough heat to affect his neighbor...

The theory is good. But I haven't seen the numbers as to what a single bad Tesla cell could do...

Is there a situation where a Tesla pack has had a cell go into thermal runaway and the pack not caught fire? That would be telling!!!
 

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It is good we haven't seen Tesla fires as a result of this type of thing. But is that a result of the design or just that their quality control has been better?
This is a good read on this general topic, out a few weeks ago, a book review. https://www.engadget.com/hitting-the-books-power-play-tim-higgins-penguin-randomhouse-153052075.html The book: Power Play by Tim Higgins: 9780385545457 | PenguinRandomHouse.com: Books by Wall Street Journal tech and auto reporter Tim Higgins.
 

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This is a good read on this general topic, out a few weeks ago, a book review.
Yep, I read that...
Eventually, Straubel began to narrow in on a solution. If they couldn’t keep a cell from warming, maybe they could keep it from reaching the point where it set off a chain reaction. Through trial and error, the team realized that if they had each cell lined up a few millimeters from its neighbor, snaked a tube of liquid between them, and dumped a brownie-batter-like mixture of minerals into the resulting battery pack, they could create a system that contained overheating. If a defective cell within began to overheat, its energy would dissipate to its neighboring cells, with no individual cell ever reaching combustibility.
Which I why I think it is a good theory. Just wondering how it works out in practice:
 

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Which I why I think it is a good theory. Just wondering how it works out in practice:
I don't see any reason why it wouldn't work really great in practice. The only caveat I see is that the temperature needed to cause problems doesn't go up as the battery cell size goes up, so as Tesla moves to larger and larger cells that contain more energy at some point I'd expect the amount of heat that can be generated by one faulty cell would be enough to set off adjacent cells as well. They might be able to increase the thickness or perhaps composition of the inter-cell adsorption material to slow the thermal transfer rate, but that might work against the increased energy density that they'd presumably be trying to achieve with a larger cell format.
 

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I don't see any reason why it wouldn't work really great in practice.
It would be a truly sad day if the lessons Tesla learned some 15 years ago were forgotten by them today. I don't know what the technical solution to this is, but I presume it exists and Tesla has it figured out.

The first thing that comes to mind would be a phase change material
 

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It would be a truly sad day if the lessons Tesla learned some 15 years ago were forgotten by them today....
Was it really a 'lesson'?
15 years ago the 18650 was the only high power, readily available Li-ion cell.
I don't think they had many choices to make during the roadster development.
And now, maybe they're just staying the course.
 

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Was it really a 'lesson'?
15 years ago the 18650 was the only high power, readily available Li-ion cell.
I don't think they had many choices to make during the roadster development.
And now, maybe they're just staying the course.
What ever they did to handle the possibility of thermal runaway worked. Whatever LG did for the Bolt didnt. I figure Tesla has the same production issues but not the runaway problem. How? No idea. Better isolation of cells? Better BMS? What ever they did is working. Maybe the pouch design flaws are untestable. Anyway hats off to Tesla wizards that worked this out.
 

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Was it really a 'lesson'?
15 years ago the 18650 was the only high power, readily available Li-ion cell.
I don't think they had many choices to make during the roadster development.
And now, maybe they're just staying the course.
I would appreciate it if you quote my entire sentence. I did not say that Tesla forgot the lesson.
 

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I would appreciate it if you quote my entire sentence...
Sorry, I did a bad clip there. I'm just trying to declutter things.
Fixed if for you! The original quote is an easy click of the up arrow.
 
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Sorry, I did a bad clip there. I'm just trying to declutter things.
Fixed if for you! The original quote is an easy click of the up arrow.
Thanks

Regarding your comment about a Tesla learning a lesson or not:

As the recently published book about Tesla makes clear, JB Straubel recognized very early on two things:

1. Packs are a thermal runaway hazard
2. They could not QC themselves to a solution

So instead they engineered a fail safe.

As arithmetic makes clear, there is still no QC solution, and as LG/GM makes clear, thermal runaway from a defective cell is an ongoing risk. It would be the height of stupidity for Tesla to become an LG/GM and say what you will about Tesla, they are not stupid.
 

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All the Tesla does this and that talk went up in flames with the Plaid.
 

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All the Tesla does this and that talk went up in flames with the Plaid.
It's possible that the Plaid juiced the pack density and reached the "Chain reaction? Yes we can!" threshold. Similarly, it would be a tragedy if the move to the new 4680 cell crossed that line.

But for the 2170-powered 3s and Ys, I think the combination of the number of units sold (an order of magnitude more than the Bolt) times the number of cells (an order of magnitude more than the Bolt) makes it really unlikely that zero of those 5 billion or so cells has burned-up. Chevy is at 0.034 billion cells. If I were shopping for a Tesla, I think I'd go for the 2170s and not wait for the 4680s. Or I might wait for LFP cells.
 

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-So instead they engineered a fail safe.
-.... It would be the height of stupidity for Tesla to become an LG/GM and say what you will about Tesla, they are not stupid.
-'engineered a fail safe'?
As in using thousands of individual cells in stainless steel cans? That's all there was available in their beginning.
Wasn't it later that the individual fusible links were part of this design? What other 'fail-safe' do they have?-

-But isn't there going to be pouch cells in some future Tesla?
 
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