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I categorize that more as cost and maybe quality. The strength of battery designed with several thousand semi-independent cylinders is that a few of those cylinders (maybe even their connections) can go south, and you still have a functioning battery. The owner might see less range, performance, capabilities, etc. compared to what the car should have, but hey, what's a few hundred Wh of capacity among friends?
Yeah, that's EM's claim. However one cell represents about a 2% loss in one "brick" That represents a 2% imbalance for the pack so effectively 1 cell is responsible for a 2% loss for the entire pack. It's actually quite an erroneous comment. More like about 1.2KWh per cell lost since now discharge needs to stop when that low brick reaches the cutoff voltage. Another cell in that same brick means another 1.2KWh loss.
 

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"While I face backlash every time I say this, Tesla is simply not interested in collaborating on charging. People can point to random tweets and messages all they want, but actions speak louder than words. To this date, Tesla has taken no action in opening their network of chargers despite automakers publicly approaching them. When Tesla opens their Supercharger Network to non-Tesla EVs, I'll be more than happy to retract my assertion that Tesla was falsely claiming any real interest in collaborating on charging infrastructure. Prove me wrong, Elon. I'll sport some S3XY short shorts if you even open the CCS Superchargers that already exist in Europe to non-Tesla EVs. My only caveat is it can't be forced by government regulation. It must be a voluntary, open invitation to non-Tesla EV owners. Go on, Elon. I've got my $69.420 ready. Didn't think so..."

You might want to place your order on those shorts now since they're backordered I suppose.
There's speculation that Tesla's new hire from Apple may be to expand the experience to the non-Tesla crowd since there's really not much to improve on for us.


Yesterday, Michael Rihani announced on LinkedIn that he left his position as senior product manager for Apple Card and Apple Cash at the Cupertino, California, company to join Tesla as the new product manager for “Supercharger User Experience and Strategy.”
 

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Discussion Starter #63
There's speculation that Tesla's new hire from Apple may be to expand the experience to the non-Tesla crowd since there's really not much to improve on for us.
That's not the sentiment I see on a number of Tesla owner groups. There's still a lot of room for improvement to the Supercharger Network beyond just opening it to non-Tesla owners. For obvious reasons, I don't do site reviews for Tesla Supercharger sites, but if I did, most of the sites wouldn't score particularly well compared to the best public charging sites.

Also, one of the biggest improvements might be the exact opposite of what you're suggesting. Michael might have been brought onboard to help Tesla owners leverage the public charging infrastructure, which is more diverse (and in many areas faster) than the existing Supercharger Network. This could include integrating those charging sites into Tesla's built-in navigation as well as providing a CCS adapter and integrated billing service similar to what Ford and Mercedes are providing to their customers.
 

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Oh I'm sure there's locations that have issues, and I suppose I'm jaded from what I read here that comparatively, my experiences have been almost flawless, but from a software perspective, which is what this guys background is, where is Tesla falling short?
It may be a west coast thing or big city issue. There will always be holiday congestion too which there's really not much other than the mobile generator you can do about it.
Some of the complaints one might have are also out of Tesla's hands like restrooms & restaurants. Just trying to read between the lines though and it doesn't sound like this guy is a hardware guy so most of the issues don't seem to be in his wheelhouse. My point is from a software POV, I don't know what else he could do to improve a Tesla owners experience. But then again, they are quite creative with coming up with improvements like battery conditioning or how many stalls are available all before you arrive or the entertainment stuff (games, careoke, netflix). There's so many different directions this could go with the robotaxi's, Tesla network, app, starlink, restaurant franchise affiliation, (years ago it was rumored that Applebys was going to put in superchargers) etc.

I think the latest OTA upgrade did incorporate the third party chargers into the navigation. Another theory is to have a tie in with local businesses, not really sure how.

How is the public charging infrastructure faster? Tesla's max out at 250 which is what the V3 is. Even the V2's are 150kW. It does seem reasonable though that it's a precursor to CCS compatibility for Tesla's.

Curious that you find the existing EA network better than the Supercharger Network. Baffling.

My thoughts for years though have been that the build out needs to ramp up biggly. Even though in my neck of the woods, I've really not compromised or had to detour, with the huge number of 3's and & Y's joining the ranks, the supercharger network is exponentially busier than the 3rd party network. If the EA and EVGO's and all the rest have an equal number of portals but 1/4 the number of EV's using them, Tesla will be in a world of hurt unless they get back on schedule.
I think until the V3 was in production, they probably held off on expanding for a few months but now, no excuse. There's also the possibility that they have been holding back on the Supercharger build-out as well as Service Centers which is another potential black eye if not already.
My biggest gripe though is splitting a charge which if you are the second car, you get about 70kW. That's not an issue with V3 of which all new superchargers currently are. We even have one that just opened up about 80 miles from here so I may have to give it a go.

The other arguments are that by making it public, it would avoid any monopoly investigations, give access to public funds, public lands,
 

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Discussion Starter #65
How is the public charging infrastructure faster? Tesla's max out at 250 which is what the V3 is. Even the V2's are 150kW. It does seem reasonable though that it's a precursor to CCS compatibility for Tesla's.
Last I checked, 350 kW is faster than 250 kW. Any questions about the 350 kW chargers in that regarded should be well and thoroughly answered by the Porsche Taycan's 270 kW peak, actual charging rate with a 10% charging speed boost slated for the next generation Taycan at the least, if it's not also provided as an OTA update for current Taycan owners. These same 350 kW chargers will likely be upgraded to 500 kW in the near future, but we're just talking about right now.

Even for Tesla owners, these chargers would be faster than the 150 kW V2 Superchargers as European Model 3s are able to charge at 180 kW on that class of public charger.

Curious that you find the existing EA network better than the Supercharger Network. Baffling.
You're straw manning again. I said "the best public chargers." I'm not necessarily referring to Electrify America when I say that, and I'm specifically referring to sites, not networks. EVgo and Recargo have both installed charging sites that are capable and compelling even by Tesla Supercharger standards with the added benefit that they are open and available to all EV owners. Though I haven't been able to check them out personally, Francis Solar is doing great work out in Oklahoma as well.

Your ignorance about the public charging infrastructure really is the perfect example of why someone like Michael would need to be brought on in order to integrate the public chargers into Tesla's navigation, route planning, and billing software. The first order of business, though, would be for Tesla to produce a CCS adapter that doesn't require a flamethrower case to transport around and isn't restricted to 125 A. At that point, Tesla owners could be rerouted when Superchargers are overbooked or simply when it's more conducive to their travel plans. It would also help those poor SR/SR+ owners who are sitting in Supercharger stalls for an hour charging up to 100% just so they can (hopefully) make it to the next Supercharger without having to drive too slowly.
 

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Discussion Starter #67
Are you saying that Tesla's can charge beyond 250kW?
No. I don't know either way what a Tesla's max theoretical charging speed is. What I know is that 250 kW V3 Superchargers are slower that 350 kW CCS chargers. That's grade school math.

The other concept you might be struggling with is that, even with the limitations of current Tesla vehicles' charging systems, those 350 kW chargers will charge a Tesla vehicle faster than 150 kW V2 Superchargers, which as far as I know are still far more prevalent than V3 Superchargers.
 

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Yeah, that's EM's claim. However one cell represents about a 2% loss in one "brick" That represents a 2% imbalance for the pack so effectively 1 cell is responsible for a 2% loss for the entire pack.
One of the things that stuck with me from my piloting days: a twin engine aircraft is twice as likely to suffer an engine failure as a single engine aircraft. Among non-commercial pilots who aren't repeatedly drilled in emergency procedures to airline standards, you're more likely to die in a twin engine aircraft because they're a lot trickier to handle when one engine fails, and you're more likely to be in that situation than the pilot of a single engine aircraft who only has one simple thing to do when his engine fails: glide down and land somewhere.

Similarly, the more cells there are in a battery pack the more likely you'll experience a failure of one of them, other factors being equal.
 

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Anyone care to put a speculative time line on when or if we see an Ultium drop in pack for our Bolts? I will go with maybe and 2025 haha.
 

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Discussion Starter #70
Anyone care to put a speculative time line on when or if we see an Ultium drop in pack for our Bolts? I will go with maybe and 2025 haha.
I don't know that GM will ever offer those as an aftermarket upgrade (it would be fun if they did). Now if you're asking when we can expect the Bolt EV or other BEV2 EVs to be equipped with the Ultium packs, 2025 might be a good guess. Whatever packs GM uses for the Bolt EUV and refreshed Bolt EV will probably be in use for at least 3 years prior to another model refresh, at which point, GM might be ready to apply the Ultium batteries across their entire EV line.
 

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I don't know that GM will ever offer those as an aftermarket upgrade (it would be fun if they did). Now if you're asking when we can expect the Bolt EV or other BEV2 EVs to be equipped with the Ultium packs, 2025 might be a good guess. Whatever packs GM uses for the Bolt EUV and refreshed Bolt EV will probably be in use for at least 3 years prior to another model refresh, at which point, GM might be ready to apply the Ultium batteries across their entire EV line.
I believe my 8 years are up in 2025. After that and depending upon price and availability I MIGHT be looking into trading in the old pack for an Ultium. The situation might be better to just trade the car in? an awful lot of variables and I think I will be waiting 4 to 6 years before I find out what is possible.
 

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Discussion Starter #72
I believe my 8 years are up in 2025. After that and depending upon price and availability I MIGHT be looking into trading in the old pack for an Ultium. The situation might be better to just trade the car in? an awful lot of variables and I think I will be waiting 4 to 6 years before I find out what is possible.
So you're looking to drop your battery pack the moment your warranty is up? My warranty is already up, and I'm driving around, worry free. :)
 

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So you're looking to drop your battery pack the moment your warranty is up? My warranty is already up, and I'm driving around, worry free. :)
Not exactly - all depends on 7 factors really all of them I won't begin to know for another 4-5 years; 1. how much I will need to drive -I won't know 'til around 2024-2025. 2. how "good" the DCFC is - that's also unknown right now. 3. What my trade in value will be like on a low mileage Bolt - I am hoping it will still be worth around $15 K - that might be wishful thinking? 4. What the Newer 2025 Bevs will cost. And more importantly what kind of capability they have and at what prices. 5. What the "trade in" or sales value of my used pack is. 6. Cost and availability of new Ultium packs. 7. almost forgot wear and tear after 8 years. I expect it to be minimal but yet there are a LOT of 100 degree days where I live - right now they are projecting record temps almost 10 days in a row of ABOVE 100!!! That's why I capitalized MIGHT. I also MIGHT win the lottery tomorrow in which case would look at top of the line Tesla - nice to dream about but not holding my breath til then.
 

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One of the things that stuck with me from my piloting days: a twin engine aircraft is twice as likely to suffer an engine failure as a single engine aircraft. Among non-commercial pilots who aren't repeatedly drilled in emergency procedures to airline standards, you're more likely to die in a twin engine aircraft because they're a lot trickier to handle when one engine fails, and you're more likely to be in that situation than the pilot of a single engine aircraft who only has one simple thing to do when his engine fails: glide down and land somewhere.

Similarly, the more cells there are in a battery pack the more likely you'll experience a failure of one of them, other factors being equal.
That was pretty much the reason for developing pouch cells to begin with. They scale to higher capacity easily and are easier to cool. As a trade off, a slightly less efficient chemistry was used so that the metal cylinder could be eliminated. Elimination of the metal cylinder reduced the weight and eliminated the necessity of an over pressure vent. Since all of this could pack together more efficiently, it promised a cell that had much higher power density and was greatly simplified.

GM has been following this approach on the Volt as well as the Spark EV and Bolt EV. Ultium is an evolution of this approach. Ultium could reduce the number of cells used on the Bolt EV to 96 from 288. For comparison, a Tesla Model 3 has about 4000 cells.

For all of these benefits, the pouch cells do require a more robust housing to protect them. This adds back some weight and so reduces the potential savings.

Tesla chose the cylindrical cell approach. These cells were more easily availably and were a more of less standard product. Panasonic probably made the best version in the industry so they were an ideal partner. In addition, the sales of cylindrical cells were in decline so Panasonic was quite interested in a new volume customer. At about the time of the introduction of the Model S, cylindrical cell production was basically in free fall and a number of factories were closing. This all pretty much went along with falling sales of laptop computers as well as the switch from cylindrical to pouch cells to make them thinner.

The falling demand for cylindrical cells seriously eroded the price so this was another plus for Tesla. This seems to be the basis for the claimed cost advantage. Otherwise, pouch cells should be less expensive to produce. Of course Tesla has sort of a lock on cylindrical cells and pouch cells are in high demand so this distorts the markets a lot. We will likely never know the complete truth.

Tesla developed a number of innovative ways to reduce the disadvantages of cylindrical cells and so far has managed to pull this off despite many doubts as to the veracity of this approach. The whole thing is sort of "anti innovation" so it attracts a lot of pessimists if you think of it in this way. (shorts anyone)

This sort of thing has really been at the root of Elon's approach of improving trailing edge technology instead of pushing the bleeding edge. The result is a product that is still new and innovative but with less risk. And of course it does not hurt to confuse the conversation from the twitter verse.

It all makes for quite interesting times.
 

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Discussion Starter #75
That was pretty much the reason for developing pouch cells to begin with. They scale to higher capacity easily and are easier to cool. As a trade off, a slightly less efficient chemistry was used so that the metal cylinder could be eliminated. Elimination of the metal cylinder reduced the weight and eliminated the necessity of an over pressure vent. Since all of this could pack together more efficiently, it promised a cell that had much higher power density and was greatly simplified.

GM has been following this approach on the Volt as well as the Spark EV and Bolt EV. Ultium is an evolution of this approach. Ultium could reduce the number of cells used on the Bolt EV to 96 from 288. For comparison, a Tesla Model 3 has about 4000 cells.
Just nitpicking here, but a couple of things. First, I don't think the chemistry was format dependent. GM and other automakers could have gone with similar NCA chemistry as Tesla; however, that chemistry is more flammable and volatile, something they wanted to avoid for automotive use. Second, the Ultium cells would reduce the number of cells required for the Bolt EV, but only by 1/3. The cells in the 2020 Chevy Bolt EV are over 60 Ah, so you'd need two Ultium 100 Ah cells to replace three Bolt EV pouch cells (essentially 96s2p).

Also (and this is why I'm so critical of cylindrical cells for automotive use), despite each cylindrical cell being individually packaged and self-contained, the battery pack still has to serve as a structural component for the car. So the cylindrical cell casing is basically wasted mass at that point.
 

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Just nitpicking here, but a couple of things. First, I don't think the chemistry was format dependent. GM and other automakers could have gone with similar NCA chemistry as Tesla; however, that chemistry is more flammable and volatile, something they wanted to avoid for automotive use. Second, the Ultium cells would reduce the number of cells required for the Bolt EV, but only by 1/3. The cells in the 2020 Chevy Bolt EV are over 60 Ah, so you'd need two Ultium 100 Ah cells to replace three Bolt EV pouch cells (essentially 96s2p).

Also (and this is why I'm so critical of cylindrical cells for automotive use), despite each cylindrical cell being individually packaged and self-contained, the battery pack still has to serve as a structural component for the car. So the cylindrical cell casing is basically wasted mass at that point.
From what I was able to gather Bolt cells are 50 amp hours... in any case, a 96s2p battery of ultium cells would be somewhere between 75 and 80 kWh depending on what voltage the cells run at (assuming somewhere in the 4V range) If you wanted to run a low voltage pack, you could get 60 kWh out of a 75s2p configuration. It would be 60 kWh at 300V pack voltage. Lower pack voltage doesn't fit with anything I have read though.

Keith
 

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Discussion Starter #77
From what I was able to gather Bolt cells are 50 amp hours... in any case, a 96s2p battery of ultium cells would be somewhere between 75 and 80 kWh depending on what voltage the cells run at (assuming somewhere in the 4V range) If you wanted to run a low voltage pack, you could get 60 kWh out of a 75s2p configuration. It would be 60 kWh at 300V pack voltage. Lower pack voltage doesn't fit with anything I have read though.

Keith
The 2017 to 2019 Chevy Bolt EV cells are 57 Ah. The pack is 171 Ah (according to EPA filing documents) for 3p configuration. The 2020 Chevy Bolt EV has ~10% more capacity, or 62-63 Ah per cell.

As for the 75s, you'll rarely see any series configuration that's not in denominations of 12. I'm not sure why that is, but most modern BMSes are broken into 12s (e.g., 84s, 96s, 108s, 120s).
 

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The 2017 to 2019 Chevy Bolt EV cells are 57 Ah. The pack is 171 Ah (according to EPA filing documents) for 3p configuration. The 2020 Chevy Bolt EV has ~10% more capacity, or 62-63 Ah per cell.

As for the 75s, you'll rarely see any series configuration that's not in denominations of 12. I'm not sure why that is, but most modern BMSes are broken into 12s (e.g., 84s, 96s, 108s, 120s).
If they Bolt had 57 amp hour cells, then we would have a 66 kWh pack. In order to have 60 kWh at 96s3p we would have a 350V pack. I go by the figures here: Tesla Model 3 & Chevy Bolt Battery Packs Examined

The relevant sections is as follows:

"When looking down on the pack as it is mounted in the car, pouch cells are oriented like books on a bookshelf, in groups. The pack consists of ten modules, two in a row. The modules on the bottom are labelled and divided into eight 5.94 kWh modules and two upper 4.75 kWh modules, for a labelled total of 57.02 kWh. Each module is compose of 3p (three in parallel) pouch cells contained in its own metal enclosure, like a book with pages. Eight of the modules contain ten 3p books, and two modules contain eight 3p, for a total of 96s, 3p. "

If you plug these numbers into a calculator (whole pack, or the individual module specifications) with a nominal 4V per cell you get 50 amp hours per cell.

Keith
 

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Discussion Starter #79
If they Bolt had 57 amp hour cells, then we would have a 66 kWh pack. In order to have 60 kWh at 96s3p we would have a 350V pack. I go by the figures here: Tesla Model 3 & Chevy Bolt Battery Packs Examined

The relevant sections is as follows:

"When looking down on the pack as it is mounted in the car, pouch cells are oriented like books on a bookshelf, in groups. The pack consists of ten modules, two in a row. The modules on the bottom are labelled and divided into eight 5.94 kWh modules and two upper 4.75 kWh modules, for a labelled total of 57.02 kWh. Each module is compose of 3p (three in parallel) pouch cells contained in its own metal enclosure, like a book with pages. Eight of the modules contain ten 3p books, and two modules contain eight 3p, for a total of 96s, 3p. "

If you plug these numbers into a calculator (whole pack, or the individual module specifications) with a nominal 4V per cell you get 50 amp hours per cell.

Keith
Capacity isn't measured from peak voltage; it is measured from nominal voltage. 57 Ah x 3 x 350.5 V (nominal) = 59,935 Wh.

Ah, and I see you have a 4 V per cell nominal. The Bolt EV's cells are actually 3.65 V nominal.
 
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