Rumor: GM May Use Cylindrical Cells in Future EV Models

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These rumors come shortly after the 4th Ultium/GM/LG battery plant is in question.

My guess is the big battery makers might be fighting the idea they’ll have to make special batteries for each automaker. It probably doesn’t make much sense to do that.

Maybe better to try to force automakers into just a few different cell formats. Take advantage of economies of scale, factory commonality, etc.


 
I might be misremembering, but didn’t Tesla pioneer and demonstrate the benefits of cylindrical cells?
Tesla set the bar. We will see how others compete once the numbers of EVs are high enough to compare the service cpapbilities and reliability / cost of ownership
Cylindrical high power cells have been around forever. Look at the range that say, Saft had from over a decade ago, from the VL5U to the VL52E.

Yes - with all their advantage AND disadvantages.

BMW has chosen to follow their 4680 form factor.

I wouldnt be surprised if GM flips as well.
I get it you’re putting a round peg in a square hole, but otherwise it’s far easier to seal, contain, fail in a consistent release direction, etc. The compressed electrode end design also is great for managing heat and removing impedance and heat flow bottlenecks.

No. Cylindrical lithium ion cells were around for decades before Tesla even existed.
agree.
 
Yes - with all their advantage AND disadvantages.

BMW has chosen to follow their 4680 form factor.

I wouldnt be surprised if GM flips as well.

BMW won’t be using the 4680.

It’ll be 4695 and 46120. 46mm x 95mm and 120mm

New format for the Neue Klasse.

Round cells are being used for the first time in the sixth generation of electric mobility batteries from the BMW Group. With a diameter of 46 millimetres and two different heights of 95 and 120 millimetres, the new cells are a perfect match for the completely redesigned and exclusively all-electric Neue Klasse architecture.”

 
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No surprise. Those ballooning li Po pouch cells are a bad idea. Sure they've got the best energy density but that's not the most important thing when you're buying a vehicle you want to own for 10-20 years. Especially if the component in question is so difficult to get repaired it's uneconomical to fix so you just junk the whole vehicle and lose your pants on that deal since you couldn't save enough to get your money's worth in the end. One reason why I'd never buy one with li Po cells.

And the thing that really scared me was when GM themselves in their own reveal stated that the battery pack can withstand a great amount of pouch swelling before it becomes an issue. But the fact that it was preemptively addressed from them anticipating it happens and its future controversy later on when really no one asked is not good look.

But I'd easily consider something with LFP chemistry like the new all electric Toyota's on sale in Asian markets.
 
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BMW won’t be using the 4680.

It’ll be 4695 and 46120. 46mm x 95mm and 120mm

New format for the Neue Klasse.

Round cells are being used for the first time in the sixth generation of electric mobility batteries from the BMW Group. With a diameter of 46 millimetres and two different heights of 95 and 120 millimetres, the new cells are a perfect match for the completely redesigned and exclusively all-electric Neue Klasse architecture.”


Good info - Basically 46X with 2 height options.

Gives them flexibility in the skateboard.
 
No. Cylindrical lithium ion cells were around for decades before Tesla even existed.

Sure they were, but the relevant question here is who puts them in an EV vs a pouch style.
 
No surprise. Those ballooning li Po pouch cells are a bad idea. Sure they've got the best energy density but that's not the most important thing when you're buying a vehicle you want to own for 10-20 years. Especially if the component in question is so difficult to get repaired it's uneconomical to fix so you just junk the whole vehicle and lose your pants on that deal since you couldn't save enough to get your money's worth in the end. One reason why I'd never buy one with li Po cells.

And the thing that really scared me was when GM themselves in their own reveal stated that the battery pack can withstand a great amount of pouch swelling before it becomes an issue. But the fact that it was preemptively addressed from them anticipating it happens and its future controversy later on when really no one asked is not good look.

But I'd easily consider something with LFP chemistry like the new all electric Toyota's on sale in Asian markets.
Pouch cells are integrated in modules and are far easier to repair than Tesla packs.
 
Ease of repair goes to the pouch.
Likelihood of failure also goes to the pouch.
I don't know that you can say that. Do you have actual data on this? The failure in both is actually pretty rare, and the early EV's which used pouches were air cooled, so comparing them to early Tesla's really isn't a sensible comparison to make.
 
I don't know that you can say that. Do you have actual data on this? The failure in both is actually pretty rare, and the early EV's which used pouches were air cooled, so comparing them to early Tesla's really isn't a sensible comparison to make.


I think its YMMV situation.
 
This does not seem to favor one design or the other for longevity/degredation:


1674720028067.jpg
 
I don't know that you can say that. Do you have actual data on this? The failure in both is actually pretty rare, and the early EV's which used pouches were air cooled, so comparing them to early Tesla's really isn't a sensible comparison to make.
Sure.

The big one so far was the bolt.
The chevy bolt battery failures are placed squarely at LG chems feet and resulted in the recall of every one that was manufactured.

Hyundai recalled 82K cars for battery replacements.

More often we see "hobbling" of the car from either a charge or discharge perspective to protect the battery.

BMW limits concurrent high speed charges after 2-3 (its not clear) the car goes into a highly reduced state of charge that Bjorn describes as slower than a leaf. This is likely one of the reasons why they have chosen to switch form factors.

Ford severely hobbled its Mach E GT to a maximum of 5 seconds of full throttle output because of heat issues. - This came as a very nasty surprise to the first customers who expected competitive performance.

Now it "appears" GM may be switching to cylindrical...
 
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Sure.

The big one so far was the bolt.
The chevy bolt battery failures are placed squarely at LG chems feet and resulted in the recall of every one that was manufactured.

Hyundai recalled 82K cars for battery replacements.

More often we see "hobbling" of the car from either a charge or discharge perspective to protect the battery.

BMW limits concurrent high speed charges after 2-3 (its not clear) the car goes into a highly reduced state of charge that Bjorn describes as slower than a leaf. This is likely one of the reasons why they have chosen to switch form factors.

Ford severely hobbled its Mach E GT to a maximum of 5 seconds of full throttle output because of heat issues. - This came as a very nasty surprise to the first customers who expected competitive performance.

Now it "appears" GM may be switching to cylindrical...
This has nothing to do with cylinder vs. pouch other than shoddy QA/QC by LGChem. There is a reason I won't own anything from LGChem, aside from the interim solution that is my C40 (for now).
 
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