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GM released a webpage with a lot of details and information on their Ultium batteries.

I don't see any information that had not already been announced...larger 100 Ah pouch cells, NCMA chemistry, BMS boards on the modules instead of remote. The smallest packs will be 120s1p. 500 volt...up from 96s3p, 400 volt. They show modules with 12, 18, and 24 cells, and describe packs with 6, 8. 10, 12, or 24 modules.

They have said they would have ten new EVs with 400 volt to 800 volt packs. I can't see how you make a 400 volt, 50 kWh pack with 100 Ah cells. Maybe the Ultium breakthrough is new math? I assume they are counting the fat Bolt with the current Bolt pack.
 

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30 GWH is capacity. Divide that by 75kwh, the size of a typical model 3 battery, and you get 400,000 cars.
I doubt GM will have 400,000 cars worth of production ready in 5 years, but I’d be pleasantly surprised if they did.
 

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Discussion Starter #4
30 GWH is capacity. Divide that by 75kwh, the size of a typical model 3 battery, and you get 400,000 cars.
I doubt GM will have 400,000 cars worth of production ready in 5 years, but I’d be pleasantly surprised if they did.
That's just Lordstown. They have other battery manufacturing facilities plus access to even more (particularly for the Chinese market).

One thing that could limit GM's overall EV production is the fact that they are also planning to license this battery technology to others. Honda has already signed on.
 

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I certainly hope their concept is successful. Competition is a good thing. Not being knowledgeable in the field of electrical propulsion (Master in Criminal Justice...) I don't have a clue as to which type of battery, cylindrical or flat has the edge. Probably depends on how you want to use them.

Rich
 

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I don't see any information that had not already been announced...larger 100 Ah pouch cells, NCMA chemistry, BMS boards on the modules instead of remote. The smallest packs will be 120s1p. 500 volt...up from 96s3p, 400 volt. They show modules with 12, 18, and 24 cells, and describe packs with 6, 8. 10, 12, or 24 modules.

They have said they would have ten new EVs with 400 volt to 800 volt packs. I can't see how you make a 400 volt, 50 kWh pack with 100 Ah cells. Maybe the Ultium breakthrough is new math? I assume they are counting the fat Bolt with the current Bolt pack.
A 120s1p configuration (5 of the 24 cell modules, or 10 of the 12 cell modules, or what ever configuration fits best) will give you 48 kWh at a pack voltage of 480 volts.... our "60 kWh" pack is actually 57 kWh, so why would you consider a "50 kWh" pack actually being 48 kWh any worse math than used with the old 50 amp hour cells?

Keith
 

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A 120s1p configuration (5 of the 24 cell modules, or 10 of the 12 cell modules, or what ever configuration fits best) will give you 48 kWh at a pack voltage of 480 volts.... our "60 kWh" pack is actually 57 kWh, so why would you consider a "50 kWh" pack actually being 48 kWh any worse math than used with the old 50 amp hour cells?

Keith
I guess in a world where we get to vote on what reality is, a pack with 25% higher voltage can still be called a 400 volt pack. They could market it as "New, and improved!" "Now with 25% bigger volts!" :rolleyes:

Oh! How about, "Twenty five percent more, no extra charge...still only charges to 400 volts." lol
 

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Discussion Starter #8
I certainly hope their concept is successful. Competition is a good thing. Not being knowledgeable in the field of electrical propulsion (Master in Criminal Justice...) I don't have a clue as to which type of battery, cylindrical or flat has the edge. Probably depends on how you want to use them.

Rich
It definitely depends on how you use them, but for automotive use, it's pretty easy to make the blanket statement that pouch cells are strictly better than cylindrical cells. Of course, that's only if you put a premium on build cost, cooling, and pack energy density.
 

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Interesting piece, thanks for posting @NewsCoulomb .

Did anyone else happen to read the other two posts linked below? In the one about the engineers behind the technology, after the overview of Jesse, is a picture of a Tesla charge port/ connector, DOH!

Let the rumors begin that GM is going to buy into the Tesla Supercharger Network for the next generation EV's 😉

 

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It definitely depends on how you use them, but for automotive use, it's pretty easy to make the blanket statement that pouch cells are strictly better than cylindrical cells. Of course, that's only if you put a premium on build cost, cooling, and pack energy density.
Eric. You are blowing gas now, and you have to know it. There are so many variables that go into the design and production of a complete traction pack, that there is absolutely no way for you as a layman to make that statement.

I am anxiously awaiting your tightly reasoned argument for why apples are clearly superior to oranges and bananas as a fruit, and why we will only be eating apples in the future.
 

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I guess in a world where we get to vote on what reality is, a pack with 25% higher voltage can still be called a 400 volt pack. They could market it as "New, and improved!" "Now with 25% bigger volts!" :rolleyes:

Oh! How about, "Twenty five percent more, no extra charge...still only charges to 400 volts." lol
It's not really different than what we already see in the EV world, where, traditionally, peak voltages are used to classify while nominal voltages are used to calculate energy capacity. The Bolt EV's NCM 622 cells have a nominal capacity of 3.65 V and will charge to a peak voltage of ~4.12 V. In a 96s configuration, the Bolt EV's pack will charge up to ~395 V. So, the Bolt EV's pack is classified as a "400 V," even though nominal voltage is ~350 V.

The NCMA cells in the Ultium batteries are likely to have a slightly different voltage (maybe higher?), but assuming the same 3.65 V nominal, a 120s configuration would result in 438 V nominal at a pack level. If these cells charge up to a peak 4.1 V, the peak pack voltage would be 492 V. If they charge up to a peak of 4.2 V, the peak pack voltage would be 504 V.

Now, to your point, getting a 50 kWh pack using 100 Ah cells would require a nominal pack voltage of 500 V, or a nominal voltage of 250 V with a 2p configuration. Neither seems likely. However, the strength of the Ultium design is that it is cell agnostic. GM was very clear in their EV Day presentation that the Ultium modules could be used with many different cell chemistries and, presumably, different configurations. It's entirely possible that GM could configure a "budget" 50 kWh pack using NCM 712 cells in 96s or even 120s configurations. For instance, a 120s2p configuration of 60 Ah cells would represent a 50 kWh pack.
 

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Discussion Starter #12
Eric. You are blowing gas now, and you have to know it. There are so many variables that go into the design and production of a complete traction pack, that there is absolutely no way for you as a layman to make that statement.
The engineers at a number of major automakers appear to agree with me. So does Pedro Lima at PushEVs. There are reasons to go cylindrical cells, sure, but they are not cost, cooling, and pack energy density.
 

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I guess in a world where we get to vote on what reality is, a pack with 25% higher voltage can still be called a 400 volt pack.
We entered that world a long time ago with all the confusion people about Mega, Giga and Terabytes (a disk drive with 8,000,000,000,000 bytes has less than 7.5 TB).
 

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I guess in a world where we get to vote on what reality is, a pack with 25% higher voltage can still be called a 400 volt pack. They could market it as "New, and improved!" "Now with 25% bigger volts!" :rolleyes:

Oh! How about, "Twenty five percent more, no extra charge...still only charges to 400 volts." lol
I didn't see any mention on that page of what pack voltage would be... did I miss it somewhere? Also, a 2p100 configuration would give you a 400V 80 kWh pack... so their low voltage pack would still be available without any fuzzy math.

Keith
 

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We entered that world a long time ago with all the confusion people about Mega, Giga and Terabytes (a disk drive with 8,000,000,000,000 bytes has less than 7.5 TB).
Yeah. Things went South pretty quickly when kilo- (when applied to memory), adopted the popular definition of 1000 (a power of 10), rather than 1024 (a power of two).

Don't get me started on the difference between the popular use of the word "theory", versus the scientific definition of "theory". I want to strangle someone every time I hear "It's only a theory!".
 

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I said, "They have said they would have ten new EVs with 400 volt to 800 volt packs." I didn't say it was in that article.

"Ultium-powered EVs are designed for Level 2 and DC fast charging. Most will have 400-volt battery packs and up to 200 kW fast-charging capability while our truck platform will have 800-volt battery packs and 350 kW fast-charging capability."


"Ultium energy options range from 50 to 200 kWh"


Our Bolt will charge to 4.167 V/cell, 400.03 V pack at 100%. It quickly drops to about 4.159 V/cell, 399.3 V pack.


12-29-18-1.jpg start at 8.08 am.jpg

If you guys are comfortable believing that GM will soon have the best battery packs in the world, and they will somehow build 400 volt, 50 kWh packs with 100 Ah cells, because their press releases say so...go for it.. My suspicion is they will be an improvement over the current pack in the Bolt, for energy density, and charging speed. Beyond that, I will wait and see.

I am old enough to remember when GM was saying that monocoque/unibody chassis construction was crap...because they used obsolete ladder frame construction after the war, and hadn't caught up.
 

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Discussion Starter #17
I am old enough to remember when GM was saying that monocoque/unibody chassis construction was crap...because they used obsolete ladder frame construction after the war, and hadn't caught up.
A friend who worked as an aerospace engineer for Boeing and Raytheon stated that he and his coworkers were well aware that GM had some of the best engineers and engineering in the auto industry. The only question for them was whether that class-leading engineering would make it into actual cars and trucks.

I have no doubt that GM's representations of their tech (and their tech advantages) are valid. To your point, though, the real question is whether we actually see them implemented. This is a new GM (not the one that "killed the electric car" or chose body-on-frame over unibody chassis), so I'm trying to stay positive.
 

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Yeah. Things went South pretty quickly when kilo- (when applied to memory), adopted the popular definition of 1000 (a power of 10), rather than 1024 (a power of two).
You have 1000 and 1024 backwards? Memory (RAM) vendors from their earliest products played fast and loose with the Si prefixes, using kilo and K to represent 1024, etc. -- convenient, but completely wrong and long-term confusing. 8-bit processors could actually access not 64KB but 65.536 KB.

Storage vendors (disk) have always used the prefixes correctly, where 8,000,000,000,000 is legitimately 8 TB, as have done network vendors, where 1 Gb/s equals 1,000,000,000 bits/second.

More recently, as storage and memory converge (flash storage), vendors have been attempting to fix the incorrect usage by popularizing the new IEC prefixes for the binary amounts (KiB, MiB, GiB, TiB = kibibyte, mebibyte, gibibyte, tebibyte). They sound ugly now, but maybe they'll stick and become natural. 8 TB ~ 7.28 TiB.
 

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You have 1000 and 1024 backwards? Memory (RAM) vendors from their earliest products played fast and loose with the Si prefixes, using kilo and K to represent 1024, etc. -- convenient, but completely wrong and long-term confusing. 8-bit processors could actually access not 64KB but 65.536 KB.
Just a bit off here. 64KB is 65,536 bytes, not 65,536 KB.

Of course in EV world we get the same confusion beween kW, which is charging speed, and kWh which is capacity.

ga2500ev
 

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I said, "They have said they would have ten new EVs with 400 volt to 800 volt packs." I didn't say it was in that article.

"Ultium-powered EVs are designed for Level 2 and DC fast charging. Most will have 400-volt battery packs and up to 200 kW fast-charging capability while our truck platform will have 800-volt battery packs and 350 kW fast-charging capability."


"Ultium energy options range from 50 to 200 kWh"


Our Bolt will charge to 4.167 V/cell, 400.03 V pack at 100%. It quickly drops to about 4.159 V/cell, 399.3 V pack.


View attachment 29797 View attachment 29798

If you guys are comfortable believing that GM will soon have the best battery packs in the world, and they will somehow build 400 volt, 50 kWh packs with 100 Ah cells, because their press releases say so...go for it.. My suspicion is they will be an improvement over the current pack in the Bolt, for energy density, and charging speed. Beyond that, I will wait and see.

I am old enough to remember when GM was saying that monocoque/unibody chassis construction was crap...because they used obsolete ladder frame construction after the war, and hadn't caught up.
From what you just said, they never stated that the 50 kWh pack will be 400 volts. If they make a 2p400s battery pack (an obvious option for them to use) it will be an 80 kWh pack at 400 volts.

Also, everything you (and everything I) have calculated is based on assumptions about the voltage of the new cells. Who is to say they are not 5 V cells, or perhaps 3 V cells? Beats me.

Keith
 
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