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BEWARE - ALERT ! GM Recalling ALL Bolt + EV Batteries from 2017 to CURRENT !

150000+ cars sold... with "several" fires... so thats maybe 10cars / 150000 or a 0.006 percent chance and even then you just have to not exceed charging to 90% capacity to avoid the issue.

yea I will take those odds in a second so send me a couple of those battery packs asap hehe

If you do not take in count the wear and tear effect. That can rise the numbers exponentially. They do the recall to go ahead of the problem.
Also they are not replacing the batteries. They only limiting the charge capacity by software.
 
If you do not take in count the wear and tear effect. That can rise the numbers exponentially. They do the recall to go ahead of the problem.
Also they are not replacing the batteries. They only limiting the charge capacity by software.
looking at the recall announcement the "interim" fix is to limit charge capacity to 90% until they can replace your battery modules...so it sounds like a battery swap.
 
looking at the recall announcement the "interim" fix is to limit charge capacity to 90% until they can replace your battery modules...so it sounds like a battery swap.
That is true.
But do you think they will sell the bad battery modules ?
To risk other fires ? (more shame and blame for them)
I think that batteries will be destroyed.
 
That is true.
But do you think they will sell the bad battery modules ?
To risk other fires ? (more shame and blame for them)
I think that batteries will be destroyed.
destroy the batteries??? oh the humanity!!!
ok factory floor reject liberators, get those battery packs out to the used battery sellers asap!!
:)
 
destroy the batteries??? oh the humanity!!!
ok factory floor reject liberators, get those battery packs out to the used battery sellers asap!!
:)
They could put it in a big pack like a Tesla megapack ... but batteries so instable ... a lot in a tight space .... kabummm ?
 
150000+ cars sold... with "several" fires... so thats maybe 10cars / 150000 or a 0.006 percent chance and even then you just have to not exceed charging to 90% capacity to avoid the issue.

yea I will take those odds in a second so send me a couple of those battery packs asap hehe
I wouldn't put them in my home, that's for sure.

Maybe if they were kept in a fireproof box with proper ventilation, or in an outdoor, concrete, enclosure. For the right price, I would take some.
 
As @svetz said, I do have some of these cells in my system. My first bank of them has now been running for 14 months. Cycling about 40% of their capacity every day. Full charge was just shy of 90% and running them down to about 50% each night. That original pack is made from the LG GM 2017 Vista 2.1 version cells. They were brand new, never cycled in a car. The GM plant evidently rejected them because the robot was not able to fit them into the car. Most likely the bolt holes didn't line up. They are an NMC chemistry which is safer than many Cobalt type cells, but can obviously still burn. They are not as safe as LFP type cells, but they hold more energy for their size and weight, and can also accept much high charge and discharge currents. The cells are rated for continuous charge at up to 1C and discharge to 3C. So fully charge in 1 hour, and discharge in just 20 minutes. Think about that for a bit. This is how the Chevy Bolt can accelerate to 60 in under 7 seconds on a 60 KWH battery. Tesla pushes their NMC cells to 5C, or full to dead in just 12 minutes.

In my use, I am charging the cells at far less than 0.1C rate, keeping the cell voltage under 4.1 volts (now down to just 4.05 volts or 82% charged) and my maximum draw so far has only been to 80 amps, which calculated back to 0.22C discharge rate. At these low current rates, the cells are running stone cold. There is no temp rise over the concrete floor of my garage. I have temp monitoring, and a smoke detector. If anything goes wrong, it is one plug, and roll the steel cabinet out of the garage. I am keeping a close on on them, but I am not worried about them.

I have now added another bank of Chevy Bolt cells. The second bank has now been online just over 2 weeks. There are 2020 cells labeled Gen 2.2 that came out of a car that was totaled with very low mileage. When I added the second bank, I lowered the full charge voltage down from the 4.10 to 4.05 volts to reduce the stress, and I also raised the low side cut off as well. My total current is a little higher, but that makes the current per bank only about 60% of what it was before. I am only cycling 30% of the cells capacity now, and the currents are even lower. At the state of charge and the currents I am using, I am not worried about the fire risk.

GM and LG have been studying the problem, and it seems they may have finally found the root cause. The first flaw is when the cells are being made, the separator sheet in 1 cell out of hundreds might have a fold in it. If it happens in only one place in a cell, it should not cause a problem. But it just cause a high spot that puts more pressure on the separators in the other layers of the cell. They do not think that this alone would cause a problem as there is a foam pad between each pair of cells to give some room for the cells to swell. But they also identified an assembly problem where the robot spot welding the cell tabs to the bus bars was evidently using too much force. This seems to have caused a few cells to end up with a small tear in the cell tab. The Chevy Bolt battery pack uses groups of 3 cells in parallel. With one of the cells having a ton tab, it will cause the group of three to not properly share the current load. The two with intact tabs carry more current, and that can cause them to swell more, and the one with the tear has higher resistance, so it will be heated from that and also cause some swelling. Combine this with a cell that has a folded separator, and the extra room for the cell to swell can be used up and the anode and cathode can get forced through the separator and cause a short. The odds of the problems stacking onto a single cell are quite slim, and I know none of my cells have any tears in the tabs. Add to that my cells never get even the slightest bit warm. Again, not worried.

The original Tesla battery design is not as energy dense. Their battery pack is much larger and heavier for a given amount of stored energy. They are using many small cells in parallel. The Bolt Design is just 3 cells in parallel, but each cell is 60 amp hours. Tesla's newer battery designs are moving to fewer but larger cells as the packaging becomes more efficient. But they are still going with metal cased cylindrical cells. Both systems use a liquid cooling system to help manage the cell temperature. In the Tesla, they have a flattened tube weaving between and contacting the case of each cell. In the Chevy Bolt design, there is an aluminum plate runner between each pair of cells, and then folding over 90 degrees above and below the cells. On the bottom side, these aluminum plates are resting on the cooling plates with the coolant flowing under the cells. A huge amount of the cells surface are is in contact with the aluminum cooling plates. Cell temperature in normal use has not been a problem with either design.

Any type of battery can become dangerous. The fact there may be a flaw inside some of my cells did make me a little nervous at first, but I am closely following the news from GM and LG and taking precautions. My brother and his wife both own Chevy Bolts, and they really like them. They are actually running a much higher risk than I am . Even with both of my battery banks, I am still at just 36 KWH of battery. With their 2 cars, they now have 120 KWH of these cells. For now they have the reduced charging limit, and they have not been using fast charging. Under the latest recall, it seems they are going to change the entire battery pack in early models, and they will open and inspect the newer models and only replace bricks that have an issue. They have not said how this will be determined though. If it is just looking for torn tabs, then I know mine are safe from that.
 
Potentially silly question: Do you think there is a chance of LG Chem doing recall replacements for any of us who bought new unused cells from Battery Hookup? I am running 84 of them in a 36kWh system.
 
Do you think there is a chance of LG Chem doing recall replacements for any of us who bought new unused cells from Battery Hookup?
No I do not think that is very likely because the Bolt battery issue is part of a vehicle recall. Only some cells have been identified as having an issue. You would have to be able to test all your cells and figure out which ones are the bad ones if in fact that cell model even has issues,
 
Potentially silly question: Do you think there is a chance of LG Chem doing recall replacements for any of us who bought new unused cells from Battery Hookup? I am running 84 of them in a 36kWh system.
I think you need to contact Battery Hookup.
 
My first group of cells were from Battery Hookup, and I clearly don't expect any kind of recall to help out with surplus cells.

My second set of cells actually came out of a completed car. So they could possibly be tracked to an actual VIN number. But again, the car they came out of was listed as a total loss. Insurance already paid out on it.

So when you use surplus and/or used cells, you are getting a good deal, but basically it is an "As Is" purchase with no warranty. I plan to keep using mine until they either lose too much capacity, or they get hot. I will be adding a few more temp sensors and maybe put a smoke detector inside each of the cabinets. Right now the smoke detector is on the wall, well above all my gear. I had it go off once while I was welding in the garage. It's not a good environment for a smoke detector.
 
When a vehicle is totaled, GM no longer supports recalls. At least that is what they were doing 20 years ago. Or maybe that was campaigns? Dang it, I'm pretty sure it's recalls and everything.

I put a wifi smoke detector in my battery box. I'll get a push alert on my phone when there is smoke inside the box. In theory I can at least stop it from catching nearby things on fire if something does happen.

I'm also planning to pull the purple foam insulation (flammable) and put in rockwool or something less flammable for insulation.
I'm also going to use cement board not plywood for the inner walls to mount the BMS, relays, heater and chiller controls.
 
Not that this will help us with our repurposed cells, but GM and LG have come to an agreement. LG will foot the bool, to the tune of 1.9 BILLION dollars to pay for the replacement battery modules in the Chevy Bolts. I am not very surprised, as it did seem pretty obvious that the fault was in their cells, and the assembly of the modules, that was also done at LG plants.

I have to wonder if all of the old modules will now end up on the surplus market, or will LG tear them all apart to find how many had a potential problem? Just imagine if they replace all of these modules, and after tear down, they only find 1 or 2 more with the flaws?

The best thing for us would be for them to torture test a huge lot of these battery modules and figure out exactly what caused them to ignite. If it truly is only fast charging and going to over 4.15 volts per cell, then we are truly quite safe with our use case.
 
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