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If you think rolling out a fast-charging network is capital intensive, imagine rolling out "plentiful" battery swap stations!
I imagine it could be cheaper actually. You don't need the demand load infrastructure, just the single open structure with one swap mechanism. Shouldn't require personnel, just a bank of batteries that auto load/store/charge. The typical supercharger station costs around $250k.
If you read the link, NIO has already proven it's feasible.
 

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The main issue with past battery swap attempts was that the cars and batteries themselves were not designed with battery swapping in mind. It's like modifying an ICE platform to be an EV. It results in a compromised platform that isn't as effective as car that was designed from the ground up as an EV.

If an EV's battery system was designed from the outset with battery swapping in mind, this would be far more effective than the previous attempts. Obviously, as energy densities increase, these swaps would become easier; however, as energy densities increase, the need for public charging and battery swaps would diminish. The combination of longer ranges, surplus battery capacity, and 100% of peak charging speeds for 90% of the usable capacity would all but eliminate the need for battery swaps. One of the biggest advantages of EVs is that time spent fueling is no longer compartmentalized, and so in some ways, battery swaps would become less convenient.

The biggest strength of battery swaps would be if a company offered them as a rental option to supplement base vehicles. For example, perhaps the next generation Chevy Bolt EV ships with a base 66 kWh battery, but it has the capacity to hold an additional 66 kWh of modules (two 33 kWh modules). On a long trip, a Bolt EV owner could rent additional modules and or swap their spent modules at battery swapping stations.

Given GM's Ultium battery technology, this is easy to imagine as the pack can accept modules with various chemistries and integrate them into a single system. Perhaps you want to rent LiFePO4, NCM, NCMA, or solid-state cells, whichever matches your budget or trip needs.
 

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Zero Motorcycles has had the battery swap in practice for almost a decade. I own a 2013 that has two 50 lb. batteries totaling 5.7 KW
The bike has 68 lb. ft of torque. With both batteries, it has 54(?) horsepower and with one battery it has same torque and 27(?) horsepower.
Tesla mentioned being able to add more horsepower as battery backs got bigger. They are up to 14.4 KW battery with 140 ft-lb torque
and 110 hp.I am not sure how early they had the swap able batteries, but, I know that a 2012 that I had also had this feature.
I wonder if Tesla saw the Zero when they thought about the battery swap idea. As mentioned previously, it would not be feasible for
a " home " option. As far as a larger battery during a swap, I believe that is one of the options being offered ( or at least discussed )
in China. Below is a link to a video from 2013 where the Zero was entered in a 24 hour endurance race. The clip is only 35 seconds
long, so the battery swap part is pretty quick.

 

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From what I recall, Tesla's foray into swapable battery packs was in response to the quirky CAFE regs which gave fuel cells twice as much of a credit per car than the current EV's based on time to refill. I think it was something along the lines of 80% in 15 minutes and was obviously crafted by the fuel cell lobbyist's. Musk being Musk fought back at the obvious bias (similar to the Ontario tax scheme where he tweaked the specs to qualify for the full credit) with the battery swap, thereby qualifying for the same credit as FCEV's. I think it was a $50 cost to swap though and as we now know, didn't catch on for a variety of reasons.

I believe the biggest reason though was that the supercharger network was growing quite rapidly and at the time, still free for all Tesla's making the need for a battery swap not necessary. If the charging infrastructure was minimal, it may have had a different outcome.

With the current density and speed of the supercharger network, especially as V3's become more prevalent, along with the Tesla Integrated Network which connects the cars to the Superchargers for trip routing, battery conditioning, payment, availability, scheduling, etc. I don't see it as a viable alternative.
 

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From what I recall, Tesla's foray into swapable battery packs was in response to the quirky CAFE regs which gave fuel cells twice as much of a credit per car than the current EV's based on time to refill. I think it was something along the lines of 80% in 15 minutes and was obviously crafted by the fuel cell lobbyist's. Musk being Musk fought back at the obvious bias (similar to the Ontario tax scheme where he tweaked the specs to qualify for the full credit) with the battery swap, thereby qualifying for the same credit as FCEV's. I think it was a $50 cost to swap though and as we now know, didn't catch on for a variety of reasons.

I believe the biggest reason though was that the supercharger network was growing quite rapidly and at the time, still free for all Tesla's making the need for a battery swap not necessary. If the charging infrastructure was minimal, it may have had a different outcome.

With the current density and speed of the supercharger network, especially as V3's become more prevalent, along with the Tesla Integrated Network which connects the cars to the Superchargers for trip routing, battery conditioning, payment, availability, scheduling, etc. I don't see it as a viable alternative.
You're probably right. I think that's also why GM is focusing on the "90% in 10 minutes" target. Depending on how the battery is configured and the usable capacity displayed, that can easily be achieved with a ~3 to 4 C average charging rate for 70% of the battery's gross capacity.
 

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One article said production starts late '21 , hope they don't weak out on the specifications. Well at least Ultium is confirmed! PS Low and Slow is good for BBQ, not for EV range and Charging!!!
 

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One article said production starts late '21 , hope they don't weak out on the specifications. Should use Ultium!
According to the story, they will be using Ultium. Also, the Cruise Automation Origin is already using a unique battery pack that could possibly be ideal for these large, flat-floor transports.
 

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If not a Micro, perhaps. Right now, I tow my Electric Motorcycle on a trailer with the Bolt.
It would be nice to have it out of the weather.
 

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Not quite on topic but an interesting interview with the battery expert at Munro Associates.
Good explanation to the differences between the different form factors.
Cylindrical-Jelly Roll
Prismatic-Grilled Cheese Sandwich
He also explains why Tesla is decades ahead of the competition which is not so much due to the batteries (other than the ability to balance the voltage which was why the legacy battery companies have shied away) but more to do with the electronics and vertical integration.
 

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Hyperbole alert. How can a company that is 1.5 decades old be "decades" ahead of the competition? Tesla started with laptop batteries that anyone can buy. Doesn't that imply that everyone else is going backwards?
 

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Not quite on topic but an interesting interview with the battery expert at Munro Associates.
Good explanation to the differences between the different form factors.
Cylindrical-Jelly Roll
Prismatic-Grilled Cheese Sandwich
He also explains why Tesla is decades ahead of the competition which is not so much due to the batteries (other than the ability to balance the voltage which was why the legacy battery companies have shied away) but more to do with the electronics and vertical integration.
Sandy, unfortunately, is out of his depth when assessing battery technologies. He seems to have fallen into the trap of "it's better because Tesla is doing it," but he fails to realize that Tesla isn't using cylindrical cells because they are better. Sandy had a display of a cylindrical cell, prismatic cell, and pouch cell batteries on a table, and he proclaimed that Tesla's cylindrical cell battery was the most energy dense, newest technology. However, even based on his own display, the exact opposite was the case.

Cylindrical cells are actually the oldest of the three form factors, and the only reason Tesla continues to use them is because they are already so heavily invested in manufacturing cylindrical cells and building cylindrical cell battery packs. Further, unless Sandy is willing to concede that GM's battery chemistry is just far superior to Tesla's in terms of energy density, he needs to explain how it is that the Bolt EV's battery has the same gravimetric energy density as the Model 3 LR's cylindrical cell battery despite the fact that the Bolt EV's battery pack is smaller and includes structural elements of the vehicle.

One of the things that I think you're going to see come out of Tesla's Battery Day is an announcement that they, too, will be moving away from cylindrical cell packs. At first, that might only be for their higher end and energy hungry models (like the Cybertruck, Roadster, and Semi), but I see them eventually moving in the same direction as everyone else (pouch cells like BYD's Blade and GM's Ultium designs). In the meantime, Tesla will continue to work on ways to improve the aging cylindrical cell format, such as removing one of the cell tabs.
 

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I imagine it could be cheaper actually. You don't need the demand load infrastructure, just the single open structure with one swap mechanism. Shouldn't require personnel, just a bank of batteries that auto load/store/charge.
When you start to think about the electromechanical infrastructure needed to safely and automatically heave around 1,000-lb batteries, the need to maintain it, the need to have an inventory of very expensive batteries on hand and space to store them - and couple that with the fact that you still need close to the same grid connection to charge the batteries for the next customer, I think you'll find that an automatic battery change station represents a much larger capital investment and operating cost than a standard EV charger. And that's not even getting to some of the thorny issues such as having to stock different types of batteries for different vehicles.

No wonder it's a non-starter.
 

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Hyperbole alert. How can a company that is 1.5 decades old be "decades" ahead of the competition? Tesla started with laptop batteries that anyone can buy. Doesn't that imply that everyone else is going backwards?
Exactly, I believe that's the point they are making. Also, 1.5 decades is plural so going backwards isn't required, it just is. At the 8:20 mark, Sandy says exactly that when discussing vertical integration where the OEM's are going in the opposite direction.
Munro is a lifelong Detroit insider that understands legacy auto better than just about anybody. He has loyalty to none but was a Ford man before going out on his own. Per the interview, the advantages that Tesla holds lie primarily in the vertical integration and first principal problem solving. See italics below.

It begins at the 12:45 mark but more importantly, they point out the corporate structure is where they are woefully behind and falling further. When the economy tanked in 2008, Tesla gobbled up all the best engineers from the top think tanks in the country.
The corporate philosophy is extremely demanding and expectations are much higher than what you find in Detroit. They are workaholics and have a drive and passion you don't see at the Big 3. 16:20 Munro's boss at Ford, VP of Powertrain, Max Derosa, "80% of you are worthless, 20% are what make the company work". At Tesla, it's just the opposite or even better at 10% worthless would be a stretch. They also mentioned the Silicon Valley mindset which separates them from Detroit, Tokyo, or Munich.

Sandy, unfortunately, is out of his depth when assessing battery technologies. He seems to have fallen into the trap of "it's better because Tesla is doing it," but he fails to realize that Tesla isn't using cylindrical cells because they are better. Sandy had a display of a cylindrical cell, prismatic cell, and pouch cell batteries on a table, and he proclaimed that Tesla's cylindrical cell battery was the most energy dense, newest technology. However, even based on his own display, the exact opposite was the case.

Cylindrical cells are actually the oldest of the three form factors, and the only reason Tesla continues to use them is because they are already so heavily invested in manufacturing cylindrical cells and building cylindrical cell battery packs. Further, unless Sandy is willing to concede that GM's battery chemistry is just far superior to Tesla's in terms of energy density, he needs to explain how it is that the Bolt EV's battery has the same gravimetric energy density as the Model 3 LR's cylindrical cell battery despite the fact that the Bolt EV's battery pack is smaller and includes structural elements of the vehicle.

One of the things that I think you're going to see come out of Tesla's Battery Day is an announcement that they, too, will be moving away from cylindrical cell packs. At first, that might only be for their higher end and energy hungry models (like the Cybertruck, Roadster, and Semi), but I see them eventually moving in the same direction as everyone else (pouch cells like BYD's Blade and GM's Ultium designs). In the meantime, Tesla will continue to work on ways to improve the aging cylindrical cell format, such as removing one of the cell tabs.
You may want to watch the interview again. Sandy is well aware he's not the expert, that's why his associate Dr. Mark Ellis was providing the color. I'm not an EE so I can't debunk or support his findings.
If you remember back to Munro's first Tesla review, he was skewered by the Tesla faithful for his criticism of fit and finish and even some of the design decisions so his newfound love affair for Tesla was a slow unpeeling of the onion and the more he exposed, the more enamored he became. This is a business for him, I doubt he can afford to be biased but I can see why you might think so based on his more recent teardowns.

Tesla's decision to go with cylindrical wasn't based on density, it was primarily due to cost, along with non-proprietary. When Tesla announced their decision to go with 7,000 cylindrical cells, rather than prismatic or pouch, they were summarily ridiculed by the legacy automakers because of the difficulty in balancing. Their (legacy) assumption was that it was too difficult to even try so by default, cylindricals were not even considered.
But as we've seen time and time again, Tesla has proven the naysayers wrong and came up with a BMS and electronics integration that was able to make it work "really well" 7:40.
It is the electronics, not the battery that leads Munro and Associates to claim Tesla is decades ahead of everyone else.
Batteries are easy, it's the electronics that are hard. 10:50. Ellis 19:40, making batteries is not easy. ?????

But since you brought up chemistries, the dry electrode technology they will be incorporating due to the Maxwell acquisition will continue to extend Tesla's cost advantage. This is brought to light with the Porsche level of margins that Tesla is getting where none of the legacies are able to turn a profit in the EV sector. You put a lot of emphasis on energy density as the be all, end all and it's much more complicated than just one specification. Tesla is also much more likely to jump ship when shown a better way than the legacy automakers so if after the dust settles, prisms or pouch or pyramid batteries are shown to be the best solution, you can bet Tesla will move in that direction.


There's also a number of BEV's that are moving to cylindrical (Lucid, Rivian,) so I don't think you can make a blanket statement that prisms are better than pouch or cylindricals are better than prisms. It's a net tradeoff of a number of factors, energy density is just one metric. You have to consider design flexibility(non-proprietary), weight distribution, (model 3 has one of the lowest centers of gravity of any production sedan available), Safety, (Tesla battery pack is a structural element that helps it earn the highest safety ratings of any car you can buy).


"Cylindrical battery cells are not regarded as superior compared to other formats of battery cells because an EV car requires more than 7,000 small cylindrical battery cells while an EV using prismatic or pouch-style batteries only requires hundreds of battery packs. But to meet various demands for battery cells of EV makers, battery producers have been producing different formats of lithium-ion cells," an official in battery cell industry said. "The trend for adopting cylindrical cells for EVs has been led by Tesla and many EV makers are trying to follow Tesla's lead."

An industry analyst said demand for cylindrical cells will be on the rise starting 2020 with more EV makers adopting cylindrical cells, and Korean battery producers such as LG Chem and Samsung SDI are expected to enjoy soaring demand.

There is expected to be a boom in the demand for cylindrical cells in 2020. Chances are increasing that cylindrical battery cells will be tight in supply as more EV makers are adopting them for their EVs including delivery EVs and truck EVs," Chang Jung-hoon, an analyst at Samsung Securities, said in a report. "


.

The tabless cell patent was filed a month ago.
 

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You may want to watch the interview again. Sandy is well aware he's not the expert, that's why his associate Dr. Mark Ellis was providing the color. I'm not an EE so I can't debunk or support his findings.
If you remember back to Munro's first Tesla review, he was skewered by the Tesla faithful for his criticism of fit and finish and even some of the design decisions so his newfound love affair for Tesla was a slow unpeeling of the onion and the more he exposed, the more enamored he became. This is a business for him, I doubt he can afford to be biased but I can see why you might think so based on his more recent teardowns.
I'm saying specifically his assessment of cylindrical cells versus prismatic or pouch cells. This specific interview might be different, but his previous statements were obviously false, even on the surface.

I do recall that Sandy was critical of the Model 3 initially, and he received so much backlash that he realized how rabid Tesla's popular support was. Sandy isn't stupid. He immediately made an adjustment to cash in.

Tesla's decision to go with cylindrical wasn't based on density, it was primarily due to cost, along with non-proprietary. When Tesla announced their decision to go with 7,000 cylindrical cells, rather than prismatic or pouch, they were summarily ridiculed by the legacy automakers because of the difficulty in balancing. Their (legacy) assumption was that it was too difficult to even try so by default, cylindricals were not even considered.
No, Tesla's decision to go with cylindrical cells was based on the fact that they were all that was available at the time. They quite literally used laptop batteries in the beginning. By the time they built their Gigafactory, they had already tooled their production lines, so that wasn't going to change.

But as we've seen time and time again, Tesla has proven the naysayers wrong and came up with a BMS and electronics integration that was able to make it work "really well" 7:40.
It is the electronics, not the battery that leads Munro and Associates to claim Tesla is decades ahead of everyone else.
Batteries are easy, it's the electronics that are hard. 10:50. Ellis 19:40, making batteries is not easy. ?????
Just because Tesla has to work harder to make their initial design work doesn't mean that their initial design is better. And let's be frank here: What Tesla is doing isn't anything special. They just happen to be doing it in the automotive space. Battleborn and Valence both do similar things with cylindrical cell LiFePO4 batteries, but their focus is lead acid battery replacements. Otherwise, their daisychained BMS systems can be scaled as much as needed.

Also, as a counterpoint, I suggest that you read some of Pedro Lima's articles on Push EVs. He goes into great detail about why pouch cells are superior both from a pack energy density perspective as well as a thermal management perspective.

But since you brought up chemistries, the dry electrode technology they will be incorporating due to the Maxwell acquisition will continue to extend Tesla's cost advantage. This is brought to light with the Porsche level of margins that Tesla is getting where none of the legacies are able to turn a profit in the EV sector. You put a lot of emphasis on energy density as the be all, end all and it's much more complicated than just one specification. Tesla is also much more likely to jump ship when shown a better way than the legacy automakers so if after the dust settles, prisms or pouch or pyramid batteries are shown to be the best solution, you can bet Tesla will move in that direction.

Yes, I'm aware of the dry cell chemistry; however, based on the data I've seen, it's still only roughly the same gravimetric energy density as GM's NCM 712 chemistry, which is the interim chemistry to be used leading up to the NCMA chemistry planned for the Ultium line.

There's also a number of BEV's that are moving to cylindrical (Lucid, Rivian,) so I don't think you can make a blanket statement that prisms are better than pouch or cylindricals are better than prisms. It's a net tradeoff of a number of factors, energy density is just one metric. You have to consider design flexibility(non-proprietary), weight distribution, (model 3 has one of the lowest centers of gravity of any production sedan available), Safety, (Tesla battery pack is a structural element that helps it earn the highest safety ratings of any car you can buy).


"Cylindrical battery cells are not regarded as superior compared to other formats of battery cells because an EV car requires more than 7,000 small cylindrical battery cells while an EV using prismatic or pouch-style batteries only requires hundreds of battery packs. But to meet various demands for battery cells of EV makers, battery producers have been producing different formats of lithium-ion cells," an official in battery cell industry said. "The trend for adopting cylindrical cells for EVs has been led by Tesla and many EV makers are trying to follow Tesla's lead."

An industry analyst said demand for cylindrical cells will be on the rise starting 2020 with more EV makers adopting cylindrical cells, and Korean battery producers such as LG Chem and Samsung SDI are expected to enjoy soaring demand.

There is expected to be a boom in the demand for cylindrical cells in 2020. Chances are increasing that cylindrical battery cells will be tight in supply as more EV makers are adopting them for their EVs including delivery EVs and truck EVs," Chang Jung-hoon, an analyst at Samsung Securities, said in a report. "


.

The tabless cell patent was filed a month ago.
Yes, those are mostly startup companies, so the primary reason for using cylindrical cells is access. A number of companies make cylindrical cells for the open market because they are used for everything from personal electronics, to vapes, to RCs. The prismatic cells that are actually designed for automotive use are basically all accounted for by the major automakers. It's going to be difficult to for any startup automaker to have consistent access to those prismatic cells.

For a company like Rivian, they can order a MWh of 2170 cells from Samsung one quarter, and if the Samsung cells aren't available the next quarter, they can then order 2170 cells from LG Chem, SK Innovation, or Panasonic.

However, in 5 years, if GM-LG can produce an excess of their new pouch cell form factor, I can see them start selling them directly to startup automakers. Honda is already ordering future cells from GM-LG, so it seems inevitable.
 

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I'm jonsing for the following from GM;
1. Ultium replacement pack for our Bolts 2017-2020.
2.mid size long wheelbase long range Delivery Van for purchased. Similar in size of Transit connect - available for purchase for non businesses.
3. Updated Bolt based on Ultium and BEV3 platform !
 
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