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Overall, it sounds similar to my suggestion about a month ago, where they start with full pack replacements and pull the packs to a central location for analysis and refurbishment. The differences are section vs pack replacement (although that remains to be seen given the labor time estimate), and using the analysis to develop a diagnostic rather than creating refurbished packs.

 

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So it sounds like if they devise a detection method all the 2017 and 2018 batteries will just get new modules if needed? No 66 kWh but possibly a new extended warranty.
Yes, it sounds like they are hoping that by dissecting the 2019 cell pouches, they will discover a defect, and find a way to detect that defect non-destructively, and if they do find such a method, then they will quit replacing all five sections in every pack.

Based on fires so-far, if the problem is a clear defect, like a folded tab, then it sounds like there should be one "bad" module within the first 1000 cars they do. If it's unclear, such as if they would need to analyze all 10,000 of those modules in a charged and discharged state, at 400X magnification ( https://dc.uwm.edu/cgi/viewcontent.cgi?article=2364&context=etd ), then they may not find it, let alone find a non-destructive way to test for it.
 

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Yes, it sounds like they are hoping that by dissecting the 2019 cell pouches, they will discover a defect, and find a way to detect that defect non-destructively, and if they do find such a method, then they will quit replacing all five sections in every pack.

Based on fires so-far, if the problem is a clear defect, like a folded tab, then it sounds like there should be one "bad" module within the first 1000 cars they do. If it's unclear, such as if they would need to analyze all 10,000 of those modules in a charged and discharged state, at 400X magnification ( https://dc.uwm.edu/cgi/viewcontent.cgi?article=2364&context=etd ), then they may not find it, let alone find a non-destructive way to test for it.
I am no Li Ion expert but it seems to me the only way to tell a bad cell from a good one is if they can identify by serial number a cluster of bad batteries from the 2019 ones. But first they need to verify what the defects are to be really sure. ****, maybe there are three defects.
This whole deal with voltages below a certain average is just to wish-washy for me. Clearly it did not work with the software final recall.
It could be a year or more before they get to my Bolt. This is B.S.
No call back from GM on a swap. I am just dirt to them.
Might be time for Plan B. Garage the Bolt, cancel the insurance and get the Fiat out of mothballs.
 

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The damage is likely caused by the combination of both problems, so if you change jobs in the future and need deep discharges it'll likely take a little while for it to build up to be a problem.
Seems like the damage associated with the defect is increased by deep discharging, but reveals itself as a fire at high states of charge, although there is one case where "high" may have been around 75% rather than the usual 95+% higher risk zone.
 

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I'm so glad I went the trade swap route rather than waiting for GM to come up with a long term solution for all Bolts affected by the recall. I totally understand that they want to fix the cars with the highest probability of fire first. Makes sense. But once again, they are trying to go the cheaper route by attempting to come up with a way to somehow identify bad modules without opening the battery packs, if possible. Sounds exactly like their solution for "final fix." Let's try to correct/identify the problem with the cheapest way possible and hope that works. How did that work out? Maybe my Bolt is lower risk than others but that means I have to trust GM's diagnostics and repair remedy in the long term. It's about perception of GMs competence in addressing this issue but I'm sorry...I'm done trusting their ability to handle the situation. If they had said, "We're going to replace battery packs across the board to assure all current owners that there is no future risk of fires," that would have went far in repairing the public perception of GM standing behind their cars and customers. Now we have a weak response of "We will replace the entire battery for a small subset of the cars, with higher capacity batteries and new warranty. Everyone else, wait while we try to find a cheaper solution for you so that we can save some money." I've spent 8 of the past 9 months in limbo, not being to use my Bolt as it was intended. There is no timeline for a fix for the lower risk cars and yet, we are further restricted in use. That says to me that GM thinks that there is a statistically significant increase in risk in my Bolt than in a 2019+ Bolt with a US made battery. Regardless of whether GM develops a diagnostic tool sometime in the foreseeable future that tells them that my battery is perfect with zero risk, there will always be a little voice somewhere saying, "Maybe this charge will be the one that burns my garage down." Only replacing all of the modules in my pack with the newer design would alleviate that nagging feeling. This is not about statistical probability. This is about whether I can trust GM telling me that my Bolt is 100% safe again. Swapping into an EUV gives me the new battery pack that I can trust which is why I'm glad I went that route.
 

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Discussion Starter · #28 ·
Seems like the damage associated with the defect is increased by deep discharging, but reveals itself as a fire at high states of charge, although there is one case where "high" may have been around 75% rather than the usual 95+% higher risk zone.
So the damage is likely caused when charging to full but is gradual. This is likely because of how the cell swells as it gets to full. The damage is done before the fire, so the last charge before might not be that critical.
 

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Is this good? Yes.

Is it the result of GM doing the least, for as long as possible, until absolutely forced into doing the right thing? Yes.

Does this mean that GM is likely to be customer-focused in the future? No.

Should we expect the same “do the minimum and we’re willing to let our customers houses burn down” approach for any future issue that may surface, whether on the Bolt or the EV Hummer? Yes.

Does this bode well for the long-term health of GM’s business by cultivating repeat buyers? No.
 

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I'm so glad I went the trade swap route rather than waiting for GM to come up with a long term solution for all Bolts affected by the recall. I totally understand that they want to fix the cars with the highest probability of fire first. Makes sense. But once again, they are trying to go the cheaper route by attempting to come up with a way to somehow identify bad modules without opening the battery packs, if possible. Sounds exactly like their solution for "final fix." Let's try to correct/identify the problem with the cheapest way possible and hope that works. How did that work out? Maybe my Bolt is lower risk than others but that means I have to trust GM's diagnostics and repair remedy in the long term. It's about perception of GMs competence in addressing this issue but I'm sorry...I'm done trusting their ability to handle the situation. If they had said, "We're going to replace battery packs across the board to assure all current owners that there is no future risk of fires," that would have went far in repairing the public perception of GM standing behind their cars and customers. Now we have a weak response of "We will replace the entire battery for a small subset of the cars, with higher capacity batteries and new warranty. Everyone else, wait while we try to find a cheaper solution for you so that we can save some money." I've spent 8 of the past 9 months in limbo, not being to use my Bolt as it was intended. There is no timeline for a fix for the lower risk cars and yet, we are further restricted in use. That says to me that GM thinks that there is a statistically significant increase in risk in my Bolt than in a 2019+ Bolt with a US made battery. Regardless of whether GM develops a diagnostic tool sometime in the foreseeable future that tells them that my battery is perfect with zero risk, there will always be a little voice somewhere saying, "Maybe this charge will be the one that burns my garage down." Only replacing all of the modules in my pack with the newer design would alleviate that nagging feeling. This is not about statistical probability. This is about whether I can trust GM telling me that my Bolt is 100% safe again. Swapping into an EUV gives me the new battery pack that I can trust which is why I'm glad I went that route.
This is very well said - right to the point
 

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Said if before, will say it again. If they're opening up packs and replacing modules the dealers are going to be the weak link. GM obviously has more faith in their dealer network than the average lay person does. I'm sure many dealers, in urban high sales/service environments, will be fine. My two local hinterland Chevy dealers won't touch EVs with a 10ft pole. I've gotten no software updates for my '17 as such so far and will continue to monitor my Bolt via OBD every time I drive it (not that that would prevent a fire by any means, but at least I can see it's a "healthy" pack by the numbers).

I will not be holding my breath for any resolution in my case any time soon unless they fly in a qualified tech or reimburse me time spent traveling to a distant qualified dealer. I'm happy the '19s are getting much needed love though! It's a step in the right direction for sure.
 

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Thread title should be changed from "GM will replace all battery modules, starting in higher risk Bolts." To "GM will replace all battery modules in higher risk Bolts. All others told to wait for GM to develop a cheaper solution if at all possible."
 

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Finally some good news - it looks like GM will be replacing all battery modules in higher risk Bolts starting in the next week or two.

Read on for full details:


What do you think? Is this enough? What else can GM do to make us whole? Let me know in the comments.
All the bolts are high risk how can they say there going to start with the high risk bolts makes no sence.
 

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I am no Li Ion expert but it seems to me the only way to tell a bad cell from a good one is if they can identify by serial number a cluster of bad batteries from the 2019 ones...
That won't work, because there have been fires in 2017 and 2018 models. Even if GM Identifies a specific batch of defective 2019 batteries by serial number, that list of 2019 serial numbers won't identify which 2017 and 2018 batteries are defective. They would have to be able to directly diagnose the presence of the defects in any given battery.
 

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That won't work, because there have been fires in 2017 and 2018 models. Even if GM Identifies a specific batch of defective 2019 batteries by serial number, that list of 2019 serial numbers won't identify which 2017 and 2018 batteries are defective. They would have to be able to directly diagnose the presence of the defects in any given battery.
What do you think is the percentage likelihood that after analyzing a number of batteries from high priority recalled 2019 models during the next many weeks, that GM will gain the ability to “directly diagnose the presence of the defects in any given battery?”


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What do you think is the percentage likelihood that after analyzing a number of batteries from high priority recalled 2019 models during the next many weeks, that GM will gain the ability to “directly diagnose the presence of the defects in any given battery?”


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About the same as the statistical risk of a fire. In fact, those probabilities may not be independent.
 

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If in the theoretical possibility that GM discovers a non-destructive way to determine which modules do not have the defect, and later uses refurbished batteries that have only the (possibly) defective modules (rather than all modules) replaced, that could allow the replacement process to be completed more quickly (since there will be less manufacturing backlog of new modules), but the end result will be less desirable (not getting a 66kWh battery with all new modules).
 

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If in the theoretical possibility that GM discovers a non-destructive way to determine which modules do not have the defect, and later uses refurbished batteries that have only the (possibly) defective modules (rather than all modules) replaced, that could allow the replacement process to be completed more quickly (since there will be less manufacturing backlog of new modules), but the end result will be less desirable (not getting a 66kWh battery with all new modules).
Significantly less desirable. I simply want all new modules. Sure, 66 kWh would be nice, but for me that is icing on the cake. I simply want the cake.


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Significantly less desirable. I simply want all new modules. Sure, 66 kWh would be nice, but for me that is icing on the cake. I simply want the cake.


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I'm with you, I really don't trust that they will be able to reliably detect these defects without taking the modules apart. So just do the right thing and give everyone new modules across the board. I really don't want a mix of new and old modules.
 
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