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One new doc has appeared at Vehicle Detail Search | NHTSA. It's now at 20 associated docs. Was stuck at 19 for a long time. I think it's https://static.nhtsa.gov/odi/rcl/2020/RCLRPT-20V701-7407.PDF submitted April 29, 2021.

It is pretty vague and mentions the software (we already know about that) and:
"GM and LG Chem’s investigation concluded that the known field incidents were likely caused by one or more rare, latent cell-level manufacturing defects in design level N2.1 batteries produced at LG Chem’s Ochang, Korea facility."

"Owner notifications of the final remedy are estimated to occur in two phases; the first on May 13, 2021 to address 2019 model year vehicles and the second on May 31, 2021 to address remaining vehicles. The final remedy will be executed under bulletin N202311731. Until the final remedy is available, an interim remedy is executed under bulletin N202311730."

From the top, the estimated percentage with defect is still 1%, just like in the Feb 2021 submission.
 

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"developed diagnostic tools to identify potential battery anomalies and replace battery module assemblies as necessary" Let me analyze this out loud and please chime in . . . we know these tools are software or firmware certainly not hardware. The battery cell replacement happens if the "new" diagnostic tools detects any anomalies (detects any problems). So my thoughts are these "software tools" are more than just passive sensors, the wording implies to me that the new diagnostics tools cause a stimulus and (I suspect) existing sensors provide data that can be interpreted as a cell is going bad. Lets assume this interpretation is accurate and the reason for rolling it out the 2019 and others later is not technically related (maybe marketing) just to keep it simple for now. My question is what are they doing? How do these new "diagnostic tools" assist in identifying a cell going bad before it fries?

If GM would provided us a just a little more data that would satisfy the minds of the technically curious I think they would be well served. Instead we get this carefully drafted announcement that requires complete trust and confidence in GM, simply said "Hey folks, we fixed it, no more problems" Ok, everyone go about your lives now, all good. Maybe am out of line here, but I think most owners want to know and deserve to hear a comprehensive understanding of the solution that was developed and is planned to be implemented. That would go much further than a politically correct, legally not binding general statement. Am not looking for for formulas or trade secrets, but I certainly believe that I deserve a more age appropriate response. Their response makes me feel like a child.
 

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@freelosophy ... forget it! They're not going to give you any details. It's a "black box" to you. It just needs to work properly and be safe. That's it.

But - here comes the criticism: this software should've already be in there! They've had four years to think about it, and they did nothing until they got caught with their pants down. And all they've done so far is blame LG every chance they get ... which is a terrible look for them. You'd think the people at the top of the company would be smarter than that.

So - there are no excuses here. They're not adding any hardware to the system. They're just (frantically) writing (and testing) software they should've already installed years ago. They knew how these batteries could fail, but instead of putting in this "defensive code" at the beginning, they rolled the dice that nothing would happen ... and they got "burned".

They're lucky none of their customers burned.
 

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But - here comes the criticism: this software should've already be in there! They've had four years to think about it, and they did nothing until they got caught with their pants down.
GM I'm sure has thought about battery safety since before Bolt began development.

Per https://static.nhtsa.gov/odi/rcl/2020/RCLRPT-20V701-7407.PDF, the first Bolt battery fires in customer cars didn't happen until March 2019 and:
"From July 20, 2020 through August 26, 2020, GM received four claims alleging that the high-voltage battery pack in a Chevrolet Bolt vehicle caused a fire. GM opened a product investigation on August 26, 2020 to investigate these claims."

It's not like GM is totally new to cars w/high voltage batteries. They had EV1, Spark EV and PHEVs like Volt along w/various non-plugin hybrids over the years.
 

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Wow, that's embarrassing GM. I use multi cell lithium batteries in RC. Before charging I always check each cell's voltage to determine the difference between the lowest and highest cell. I do the same check after charging each cell of the battery pack to a full to 4.2 volts. As I soon as I see a cell not charging or discharging in harmony with others I know the battery pack is on the way out. If GM is now checking individual battery cell voltages and comparing them to others to identify potentially bad packs, then absolutely that's a good fix. Then GM replaces the affect cell or pack as needed. That's a all good! Ironically, I use a .1 volt difference to determine pack health. If one cell charges to 4.2 and another to 4.1 I know problems are coming. I don't stop using the battery until it gets worse but I keep a real close eye on it. This is what I do with my lithium battery used in toys. The embarrassing part is that GM has now figured out that lithium cells voltages need to be checked when charged and discharged and if out of spec they need to be replaced before they burn up. Really, am floored, don't know what to say or think, My GOD all this time the Bolt has not compared the lowest cell voltage to the highest to test cell health? Wow, Shame shame GM. No wonder they don't want to talk about it, and no surprise that some Bolts caught fire. I thought it was dumb for the Leaf to not have battery conditioning. And now we find the Bolt doesn't check and compare individual cell voltages. Well, based on the lithium batteries I've experienced, I feel confident in saying that all cells will fail eventually. What about the next step? We need not just the ability to detect bad cells, but to electrically isolated them from the rest of the pack. When a cell is deemed to be bad and its out of warranty then what? Just keep driving and hope there's no fire? Replace it no matter what? How about if am short of cash and am ok with the reduced range? Consider that when a bad cell is detected, it's charged to a storage voltage and then electrically isolated from the rest of the battery. The Bolt range is reduced but the Bolt would still be safe to drive and if it's out of warranty I may decide to take the miles hit than to take the dollar hit. Still I have a car I can drive with out risk. Who thinks GM has considered this? LOL no way bro! Am not a betting man but I would bet on this one LOL ! BTW I still love my Bolt sold my 2017 back to GM. GM uses the lemon law to determine you car's worth and it's different in every state. CA is very good for consumer when it comes to the lemon law. So I had them buy it back and got a 2019. Very happy with how this recall work out for me. Good luck to others still struggling with it and to GM am speechless other than WOW.
 

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"developed diagnostic tools to identify potential battery anomalies and replace battery module assemblies as necessary" .........................trust and confidence in GM, simply said "Hey folks, we fixed it, no more problems" .........most owners want to know and deserve to hear a comprehensive understanding of the solution that was developed and is planned to be implemented.
Yes, it sounds like the pre-Barra era of GM. When Barra took over, she pledged they wouldn't treat customers like dirt, especially in those types of cases where the customer could get killed in a fire, or their house burned. Of course, Barra's intentions or empty statements, whatever they were back then, got thrown away in a hurry. This is where the NHTSA needs to step in. They have the authority to say how this Recall goes. Full disclosure could be part of it. If GM doesn't cooperate, then all Bolts can't be sold & all used Bolts are required to be bought back. This is the way the FAA has done it for years for airlines & aircraft.

The principle is easy to understand. GM & LG give up their rights to private tech where said tech burns up cars, houses, or people.

As of now, the NHTSA is probably close to losing patience with GM & LG. A few more Bolts burn up, and watch the fireworks at the NHTSA happen. So far, not enough Bolts have burned up, there is that. (The standard is the rate of new cars burning up in all the last 10 years.)

I'd be the first to say the customer DOES NOT deserve internal details of a fix, UNLESS the company just threatened the lives of all Bolt owners, which happened here. That changes priorities in a hurry. If we & the NHTSA don't have common sense about this, then GM & LG batteries get away with saying "These might burn your house down or kill you while driving, but don't worry, we'll put in a secret fix, trust us, we're corporations who never deceive the public." Yeah, right. Some of us are smarter than that.
 

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wish more of us were and cared, can't let BIG organizations get away with it or they'll do more. If you don't know your rights you have no rights.
 

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I'll just stick my nose in as a Kona EV owner to mention that we have had a similar-sounding software patch in place for about 6 months, one that looks for problems while the car is parked or under charge and "bricks" the car if found. Even with that, we are restricted to a temporary max SoC of 80% (U.S.) or 90% (elsewhere globally) and expect to have full battery pack replacements for those cars containing defective cells, apparently those made in Nanjing, China.

I fully expected GM to pinch pennies but nothing as brazen as expecting Bolt owners to carry on with a known defect on board. It was two fire events subsequent to the fore-mentioned software patch that triggered Hyundai corporate to announce pack replacements. Once technical note is that from what I've seen the BMS cell voltage measurement in the Bolt has 10-20 times higher resolution that in the Kona, a critical tool to detect unexpected open-circuit voltage drop in the parallel set of three 60 Ah cells that we both have.
 

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I fully expected GM to pinch pennies but nothing as brazen as expecting Bolt owners to carry on with a known defect on board.
A known defect that only affects 1 in 10,000 Bolts, to be fair. Also, limiting total charge helps reduce the risk down lower. It is true GM invented "brazen", yet the NHTSA was probably about to force full battery pack replacments if there were any more Bolts catching fire, which would put it above the fire safety rate for ICE cars.
It was two fire events subsequent to the fore-mentioned software patch that triggered Hyundai corporate to announce pack replacements. One technical note is that from what I've seen the BMS cell voltage measurement in the Bolt has 10-20 times higher resolution that in the Kona, a critical tool to detect unexpected open-circuit voltage drop in the parallel set of three 60 Ah cells that we both have.
No Bolts have caught fire since the recall, there is that. Also, remember the voltage changes with temperature in small amounts, which would be mere useless noise at high volt meter resolutions. GM & LG must be looking for some correlated things with better algorithms to detect problems going forward. What IS strange is how they expect to stop a runaway internal short, since the only way to thwart that is to short out the terminals across a resistive load to dissipate all that energy fast, and I've never seen evidence of a resistor energy dump capability.
 

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Discussion Starter · #111 ·
I have the Repurchse letter today. CHEYANNE was great and quick to reply to emails, and I mean Quick.
I am in Mass, 2017 full premier, new, own it outright, called March 19th at 37,500 miles. Wish I had called back in November! But was hoping GM would do us right....
Amount was -$15,855.35 usage fee. Check will be just under $28,400

As far as GM goes..... I will Never own another GM again. Not just because of this but the way their service dept BS is at 2 different dealers and the crappy workmanship of the Bolt in general.
Now I know many of you are happy and I am glad for that. Unfortunately mine had Every single issue that the Bolt has happen to it... even had the transmission replaced. That I bet was the 1st one done or ever done.

Anyway, good luck to you all and I hope it runs for 200 000 miles
Peace out
 

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GM I'm sure has thought about battery safety since before Bolt began development.

Per https://static.nhtsa.gov/odi/rcl/2020/RCLRPT-20V701-7407.PDF, the first Bolt battery fires in customer cars didn't happen until March 2019 and:
"From July 20, 2020 through August 26, 2020, GM received four claims alleging that the high-voltage battery pack in a Chevrolet Bolt vehicle caused a fire. GM opened a product investigation on August 26, 2020 to investigate these claims."

It's not like GM is totally new to cars w/high voltage batteries. They had EV1, Spark EV and PHEVs like Volt along w/various non-plugin hybrids over the years.
Right ... but what are you saying here? Are you criticizing them, or making excuses for them? I can't tell ...
 

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A known defect that only affects 1 in 10,000 Bolts, to be fair.
Yeah, but it's also a small group of homogeneous owners driving Bolts: forward-thinking, smarter and more disciplined than the average car owner.

So maybe the real reason there haven't been more fires is a commentary on how these Bolts are actually being used: as commuter cars, charged almost exclusively at home, and only between 20 and 80%.
 

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So maybe the real reason there haven't been more fires is a commentary on how these Bolts are actually being used: as commuter cars, charged almost exclusively at home, and only between 20 and 80%.
How do you know that they're being charged between 20 and 80%? '17 and '18 Bolts only had a hilltop reserve on/off toggle. HTR on = ~88%, IIRC. I don't have any data (GM might) on what % of Bolt drivers leave it on vs. off and charge to 100%.

Is there evidence to suggest that even 50% of pre-'18 Bolt drivers are intentionally cutting off charging at ~80% thru some means (e.g. their EVSE lets them by guesstimating, unplugging early, setting scheduled charging to end late so they stop at ~80%)?

'19+ Bolts have a target charge level screen (I have a' 19) that let you specify 40 to 100% in 5% increments instead of HTR but I don't recall any guidance from GM in the manuals saying to go to 80%. As such, so many people I've seen here and on Bolt FB groups seem unconvinced (or don't know or don't care) about high SoC for long periods of time being bad for li-ion batteries from a degradation POV. So, they make various statements or excuses for why they believe it's ok to go to 100% all the time.

Those who leasing Bolts who have no intention of purchasing are less likely to care.
 

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I've charged my 17 to 100% a thousand times by now and the car has sat at 100% for thousands of hours. So far, so good.
 

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I wonder if someone is jumping to conclusions. Looks like a lawnmower and a motorcycle in the garage on the right. Fire could have easily started anywhere in the garage. It even looks like the damage is most severe by the lawnmower.
 

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A little late for this Bolt.

Optics on this are terrible. BTW, might want to create a separate thread to discuss this specific bit of news if it gets updated with information definitively identifying the Bolt as the primary source of the fire.
 

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I've charged my 17 to 100% a thousand times by now and the car has sat at 100% for thousands of hours. So far, so good.
Sure, so have some Leaf drivers. Their car runs fine but I'm certain this person below degraded their battery unnecessarily by a lot. They are in a super mild climate.

And, as I pointed out at 2013 Battery Bars half way - My Nissan Leaf Forum, their manual had all sorts of hints about 80% being "long life mode", warnings about frequently charging to 100%, staying above 80% SoC for long periods of time, etc. Yet, they somehow didn't know: 2013 Battery Bars half way - My Nissan Leaf Forum. They didn't RTFM.

They have 6 capacity bars left (thinnest bars all the way on the right, including the red ones). From Battery - Electric Vehicle Wiki, they probably have 47.5 to 53.75% capacity remaining.

Their car had crap chemistry (from the build month) but I suspect if they properly treated their battery, they'd be at 8 or 9 capacity bars now, possibly even 10 due to their super mild climate.

(My 5/2013 built '13 Leaf w/68K miles which has a better chemistry (Nissan seemed to quietly change it starting with 4/2013 build months) is still at 11 capacity bars but nearing based upon what I see in Leaf Spy. I'm in a much hotter climate than them.)
 

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Yes, it sounds like the pre-Barra era of GM. When Barra took over, she pledged they wouldn't treat customers like dirt, especially in those types of cases where the customer could get killed in a fire, or their house burned. Of course, Barra's intentions or empty statements, whatever they were back then, got thrown away in a hurry. This is where the NHTSA needs to step in. They have the authority to say how this Recall goes. Full disclosure could be part of it. If GM doesn't cooperate, then all Bolts can't be sold & all used Bolts are required to be bought back. This is the way the FAA has done it for years for airlines & aircraft.

The principle is easy to understand. GM & LG give up their rights to private tech where said tech burns up cars, houses, or people.

As of now, the NHTSA is probably close to losing patience with GM & LG. A few more Bolts burn up, and watch the fireworks at the NHTSA happen. So far, not enough Bolts have burned up, there is that. (The standard is the rate of new cars burning up in all the last 10 years.)

I'd be the first to say the customer DOES NOT deserve internal details of a fix, UNLESS the company just threatened the lives of all Bolt owners, which happened here. That changes priorities in a hurry. If we & the NHTSA don't have common sense about this, then GM & LG batteries get away with saying "These might burn your house down or kill you while driving, but don't worry, we'll put in a secret fix, trust us, we're corporations who never deceive the public." Yeah, right. Some of us are smarter than that.
I think NHTSA will lose their patience after this weekend's fire.
 
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