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Discussion Starter #1
Interesting... apparently, GM is moving away from LG Chem drivetrains, while continuing to partner with them on battery manufacturing.

Not surprising given GM did a lot of the engineering for the LG produced drive units. Maybe the margins are not all that great for LG and they prefer shifting resources to battery operation?

This makes the Ultium platform partnerships with Honda and Nikola make even more sense. Spread the development costs as widely as possible.
 

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I'd say the bulk of what makes an auto manufacturer is the engine, that, and the chassis. Much of the other stuff is often 3rd party suppliers. Makes sense to bring engine (engine and motor are synonymous) building inhouse.
 

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I'd say the bulk of what makes an auto manufacturer is the engine, that, and the chassis. Much of the other stuff is often 3rd party suppliers. Makes sense to bring engine/motor building inhouse.
Yup. These platform sharing agreements are no doubt short term as well. VW, GM, etc sharing platforms with companies that otherwise face years of R&D time and cost to develop their own. So, source from another company until you can get your own tech on the table.

The good news is, platform sharing agreements work to both companies advantage. They lower fixed cost allocations to the supplier, and reduce R&D costs to the buyer. Both help bring cost competitive cars to market, benefitting consumers.

LG is making drivetrain units for others as I recall. So, they likely anticipated this and will have no problem with the arrangement.
 

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In the EV era the battery is going to be just as important a component as anything else.
Of course, but chemical companies already have a leg up in that department, and the automotive equivalent is the gas tank which I bet more often than not is built by a 3rd party supplier.

And the software as Volkswagen has learned. It's definitely a step in the right direction for GM.
Yes, for sure. The shift to EV will further commoditize automobile manufacturing, with the real money being in subscriptions and purchasing of software enabled features.
 

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So this is interesting. GM also designed the motor in the Chevy Bolt EV, but they outsourced the manufacturing. This looks to be as much a marketing and PR move as anything else (they even threw in the term "vertically integrated"), and by having an internally branded line of "Ultium" motors, they shutdown the naysayers before they get started. I'm sure Electrek and Teslarati will still find ways to refer to the Lyriq as a "Google and LG EV" all the same. :rolleyes: Even this article has the snuck premise that Tesla is somehow in the lead in terms of design and technology.
 

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I'd say Tesla is handily in the lead as far as ingenuity. That doesn't mean they are better in all aspects, only that they show more willingness to try new approaches.

Purposely running a motor inefficiently to generate waste heat for cabin warming is a brilliant idea. Perhaps not as ideal as a heat pump, but it seems like a better design than resistance heating a separate fluid reservoir.

You're critical of their battery design, which is fair. I'd expect Tesla to continue innovating in that department as well, adopting other strategies if engineering and design dictate it.
 

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You're critical of their battery design, which is fair. I'd expect Tesla to continue innovating in that department as well, adopting other strategies if engineering and design dictate it.
Every legacy maker on the planet is gasping to catch up with Tesla. As for batteries...we will have to wait for battery day to see who is clearly in the lead. All Tesla has to do is hang on until governments restrict ICE so heavily that all the legacy makers' money making ICE capabilities become a wasted sunk cost.
 

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I'd say Tesla is handily in the lead as far as ingenuity. That doesn't mean they are better in all aspects, only that they show more willingness to try new approaches.

Purposely running a motor inefficiently to generate waste heat for cabin warming is a brilliant idea. Perhaps not as ideal as a heat pump, but it seems like a better design than resistance heating a separate fluid reservoir.

You're critical of their battery design, which is fair. I'd expect Tesla to continue innovating in that department as well, adopting other strategies if engineering and design dictate it.
Tesla doesn't purposely run their motor inefficiently. They built around an inefficient induction motor platform, and they made the most by routing the waste heat to the battery and cabin. GM did the same thing with the Bolt EV's coolant loop design, though there's a lot less waste heat to scavenge (not enough to heat the battery on its own and certainly not enough to heat the cabin).

Again, Tesla does great work with the technology at their disposal (I suppose that is ingenuity); however, the technology at their disposal is far from the most advanced. Tesla's strength is in using what they have, which gives them an advantage over automakers who spend a long time vetting their technology before putting it into practice.
 

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Tesla doesn't purposely run their motor inefficiently. They built around an inefficient induction motor platform, and they made the most by routing the waste heat to the battery and cabin. GM did the same thing with the Bolt EV's coolant loop design, though there's a lot less waste heat to scavenge (not enough to heat the battery on its own and certainly not enough to heat the cabin).

Again, Tesla does great work with the technology at their disposal (I suppose that is ingenuity); however, the technology at their disposal is far from the most advanced. Tesla's strength is in using what they have, which gives them an advantage over automakers who spend a long time vetting their technology before putting it into practice.
I read somewhere Tesla can generate more waste heat on demand at the motor, but maybe that was inaccurate. The point was they didn't have a different reservoir for cabin heating or a heating element. I'm curious now.

Good point about using existing tech. A new manufacturer must be scrappy to survive. I've heard great things about their PM motors though. It makes sense in a dual motor configuration to use a cheaper induction motor for the occasional times where more power or traction is needed, and a more expensive and efficient rare earth motor the majority of the time.

I'd like to see what Tesla could build at the $25k price point.
 

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Every legacy maker on the planet is gasping to catch up with Tesla. As for batteries...we will have to wait for battery day to see who is clearly in the lead. All Tesla has to do is hang on until governments restrict ICE so heavily that all the legacy makers' money making ICE capabilities become a wasted sunk cost.
I don't think the actual chemical makeup of the batteries is the secret sauce as much as the ability to ramp production at a lower cost per Kwh. That's where Tesla has led the industry and will continue for the foreseeable future. Battery Day most likely will further distance themselves in that arena.

The cylindrical form factor that Tesla, Lucid and a few others are using has an advantage both in density and cost as we've seen as well as performance and efficiency based on real data (Tesla) and proposed (Lucid) which are so far unmatched. There's also a rumor that they are increasing the size of the cylindrical cell which could be to facilitate the tabless design mentioned below.


"Panasonic introduced the “2170” lithium-ion cells, with the nickel-cobalt-aluminium (NCA) cathode chemistry, for Tesla’s Model 3 in 2017. Researchers say it already has the highest energy density at above 700 watt-hour per litre."


"So, the Bolt EV gravimetric (weight) energy density is less than Tesla’s 2170 by around 4%. Not a bad showing in our opinion. Especially since Bolt EV owners seem to be exceeding GM’s rated pack minimum energy and Tesla Model 3 owners are not. Considering that, we could almost call it a draw on the Bolt EV versus Tesla 2170 energy density by weight.
The volume of one Bolt EV cell is also an estimate. We will use dimensions of 270mmX100X 16.5=.446 liters (electricrevs ref). This may be an optimistic number. We can also calculate it from John Kelley’s video. He measured the width, height, and depth of module 1 and 10 in his Bolt EV battery reassembly video (ref@44:00:00) There are 60 cells in those two modules. So, dividing by 60 we get the dimensions of one Bolt EV cell as 16mmX 108X343= .592 liters (vs the .446 liters we used in our calcs). However, the 343mm length number includes a circuit board, so these volume numbers may be a bit high. We would have to subtract some for the circuit board. JeffN says he knows of someone with a disassembled Bolt pack and may provide us with an update on both weight and volume later.
That puts the volumetric energy density of one Bolt EV cell at 198 /.446=
444 watt-hours/liter.

*Quibbling about the correct volume to use for Bolt EV is a bit pointless since it is quite a bit lower than Tesla’s volumetric energy density= 711 watt-hours/liter by 38%."


There are other reasons and technologies that further add to the cylindrical format's advantages at least in regard to Tesla and that is the dry electrode and tabless patent. The Maxwell and Hibar acquisitions were a big part of that. Both of those are a large reason Tesla is able to have the lowest costs and highest performance. If there were another form factor that proved better, they would use it. I'm actually a bit surprised that they don't use off the shelf pouch batteries for the semi but there may be more on that discussed on the 22nd.

I really expect Battery Day to be more insightful regarding Tesla Energy however. That's more where the million mile battery is targeted other than the Semi and Robotaxi's. I hope that there's more data that helps define what a Million Mile Battery actually means though. I already have a million mile battery in my car as do Bolts. There's a bunch of Tesla's approaching that now. The trick is keeping degradation below a certain threshold after 7,500 cycles and what is that threshold?

 

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I read somewhere Tesla can generate more waste heat on demand at the motor, but maybe that was inaccurate. The point was they didn't have a different reservoir for cabin heating or a heating element. I'm curious now.

Good point about using existing tech. A new manufacturer must be scrappy to survive. I've heard great things about their PM motors though. It makes sense in a dual motor configuration to use a cheaper induction motor for the occasional times where more power or traction is needed, and a more expensive and efficient rare earth motor the majority of the time.

I'd like to see what Tesla could build at the $25k price point.
I believe that might be true for the newer models, but it's simply an extension of lessons learned from previous models that only had induction motors. Regardless, all it is is a loop that can route waste heat to the battery when needed. I'm toying with doing something similar with my Ford Ranger Electrics.

Yes, Tesla was the first automaker to use switched reluctance permanent magnet motors in an EV; however, switched reluctance motors are actually a fairly old technology (dating back to the 1970s). Dyson has been using them in vacuums for a couple of decades at this point.

Also, I have my doubts about what Tesla could actually provide at a $25,000 price point. Part of their issue is that, while the individual components of their batteries are relatively cheap to manufacture, the packaging and construction of the battery appears to be quite expensive. Enough so that Dyson (who was attempting to make their own EV) quit when trying to copy Tesla's battery model strategy, citing that the construction process for the battery made their vehicle unprofitable. Considering the single most expensive component of an EV is the battery, and the best Tesla is able to do at $35,000 is a 50 kWh pack in the SR, I'm just not sure what else they could trim to bring the cost down another $10,000.
 

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I don't think the actual chemical makeup of the batteries is the secret sauce as much as the ability to ramp production at a lower cost per Kwh. That's where Tesla has led the industry and will continue for the foreseeable future. Battery Day most likely will further distance themselves in that arena.

The cylindrical form factor that Tesla, Lucid and a few others are using has an advantage both in density and cost as we've seen as well as performance and efficiency based on real data (Tesla) and proposed (Lucid) which are so far unmatched. There's also a rumor that they are increasing the size of the cylindrical cell which could be to facilitate the tabless design mentioned below.


"Panasonic introduced the “2170” lithium-ion cells, with the nickel-cobalt-aluminium (NCA) cathode chemistry, for Tesla’s Model 3 in 2017. Researchers say it already has the highest energy density at above 700 watt-hour per litre."


"So, the Bolt EV gravimetric (weight) energy density is less than Tesla’s 2170 by around 4%. Not a bad showing in our opinion. Especially since Bolt EV owners seem to be exceeding GM’s rated pack minimum energy and Tesla Model 3 owners are not. Considering that, we could almost call it a draw on the Bolt EV versus Tesla 2170 energy density by weight.
The volume of one Bolt EV cell is also an estimate. We will use dimensions of 270mmX100X 16.5=.446 liters (electricrevs ref). This may be an optimistic number. We can also calculate it from John Kelley’s video. He measured the width, height, and depth of module 1 and 10 in his Bolt EV battery reassembly video (ref@44:00:00) There are 60 cells in those two modules. So, dividing by 60 we get the dimensions of one Bolt EV cell as 16mmX 108X343= .592 liters (vs the .446 liters we used in our calcs). However, the 343mm length number includes a circuit board, so these volume numbers may be a bit high. We would have to subtract some for the circuit board. JeffN says he knows of someone with a disassembled Bolt pack and may provide us with an update on both weight and volume later.
That puts the volumetric energy density of one Bolt EV cell at 198 /.446=
444 watt-hours/liter.

*Quibbling about the correct volume to use for Bolt EV is a bit pointless since it is quite a bit lower than Tesla’s volumetric energy density= 711 watt-hours/liter by 38%."


There are other reasons and technologies that further add to the cylindrical format's advantages at least in regard to Tesla and that is the dry electrode and tabless patent. The Maxwell and Hibar acquisitions were a big part of that. Both of those are a large reason Tesla is able to have the lowest costs and highest performance. If there were another form factor that proved better, they would use it. I'm actually a bit surprised that they don't use off the shelf pouch batteries for the semi but there may be more on that discussed on the 22nd.

I really expect Battery Day to be more insightful regarding Tesla Energy however. That's more where the million mile battery is targeted other than the Semi and Robotaxi's. I hope that there's more data that helps define what a Million Mile Battery actually means though. I already have a million mile battery in my car as do Bolts. There's a bunch of Tesla's approaching that now. The trick is keeping degradation below a certain threshold after 7,500 cycles and what is that threshold?

Umm, those numbers are laughably inaccurate. I'm going to need them to show their work for how they calculated a NCA 2170 cell's energy density at 711 Wh/L. 🤣 Each 2170 cell has a volume of 0.09698 L. If each cell contains 17.3 Wh (see below), that's a energy density of less than 180 Wh/L.


Considering the previous generation Bolt EV cells (referencing Jeff's same article) contain 216 Wh of energy in a package that's only 0.5445 L, the Bolt EV's cells are quite a bit more energy dense at nearly 397 Wh/L.
 

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I have Newscoulomb on ignore but happened to open the forum without logging in and saw you're questioning the density. I can't reply directly to your link but in the article I posted above, it shows the work but in a nutshell, your math is wrong on volumetric measurement of a cylinder. Maybe Greg or one of the other physics teachers can chime in as I'm certain you won't take my word for it but:
21mm diameter=10.5mm radius^2 * 3.1416 * 70 mm= 24,245 cubic mm /10,000 cubic mm/cubic liter =.024245298 cubic liters.
You have it at .09690 cubic liters, off by a factor of 4. This could explain a lot of your misperceptions.
 

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Either they just Osborned their lineup for the next few weeks or cars are being delivered with these soda cans already in them.
Based on some of the You tube videos that had already leaked this, it should increase range and reduce weight as well as costs. A win-win-win. I believe the tabless patent is what makes these superior to the 2170's by reducing resistance thereby allowing effective cooling to a core that is 25% further from the shell but less heat to dissipate.
The second video is more comprehensive.

 

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I have Newscoulomb on ignore but happened to open the forum without logging in and saw you're questioning the density. I can't reply directly to your link but in the article I posted above, it shows the work but in a nutshell, your math is wrong on volumetric measurement of a cylinder. Maybe Greg or one of the other physics teachers can chime in as I'm certain you won't take my word for it but:
21mm diameter=10.5mm radius^2 * 3.1416 * 70 mm= 24,245 cubic mm /10,000 cubic mm/cubic liter =.024245298 cubic liters.
You have it at .09690 cubic liters, off by a factor of 4. This could explain a lot of your misperceptions.
Ah, yes, good catch. I used diameter instead of radius, so over 40 of the 2170 cells should fit in a liter. That is pretty good energy density, and it should be interesting to figure out why the gravimetric energy density can be so similar with the volumetric energy density so different.
 
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