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To this date I am not aware of any oem that is using small cylindrical cells. Tesla,thus far, is the only company able to mass produce battery packs with these cells. Each cell is indivually connected and fused. This does not seem that easy to me.
Cylindrical cells have higher density, lower cost, and are safer. For instance Bolt battery is 57kwh and M3 battery is 75kwh but they weight about the same. https://www.quora.com/Why-does-Tesl...d-not-prismatic-batteries-like-the-Chevy-Bolt
It is much more difficult to manage thousands of small cylindrical cells so all the the other manufactures took the easy way out. However unless they manege to master this technology in the future, they will not be competitive with TSLA on this point alone.
Using pouch cells makes assembling the pack easier. The materials in the cells are larger and it probably takes a bit less time per KWH to assemble the cells. The problem is larger cells are more difficult to keep at optimum temperature. Tesla used the 18650 initially because it was a commonly available size, but they identified the 2170 as the optimum cell format for the trade off between capacity per cell and the ability to cool the cell effectively.
Right now Tesla is the only company that makes a high performance EV and the only EV that is built for real fast charging. The few other EVs that can be DC charged charge at much lower rates than Teslas. There will be faster DC chargers and cars that can handle it coming to market soon, but I wonder if they are going to have problems with keeping the battery cool enough during fast charging and hard driving in hot weather?
The physics of li-ion chemistry puts some hard limitations on what you do with them. You can slow charge them and drain them relatively slowly and they will do OK, but draw a lot of current quickly or try to recharge them quickly and they get hot. The more current going in or out, the hotter they get. And heat kills, one way or another (either premature aging or actual fire). Tesla uses relatively small cells that can be surrounded by a good cooling system so they can push the cells hard and not destroy them.
Other makers so far have used larger cells that are easier to manufacture, but they get around the heat problem by limiting the car's performance and charging characteristics.
The new EVs coming out with better performance but pouch cells might find fast degradation from heat build up. I wonder how the news will treat the first Mission E battery fire? Especially if it happens at a super fast CCS charger. Maybe somebody figured out how to make easily cooled pouch cells?
Right now Tesla is the only company that makes a high performance EV and the only EV that is built for real fast charging. The few other EVs that can be DC charged charge at much lower rates than Teslas. There will be faster DC chargers and cars that can handle it coming to market soon, but I wonder if they are going to have problems with keeping the battery cool enough during fast charging and hard driving in hot weather?
The physics of li-ion chemistry puts some hard limitations on what you do with them. You can slow charge them and drain them relatively slowly and they will do OK, but draw a lot of current quickly or try to recharge them quickly and they get hot. The more current going in or out, the hotter they get. And heat kills, one way or another (either premature aging or actual fire). Tesla uses relatively small cells that can be surrounded by a good cooling system so they can push the cells hard and not destroy them.
Other makers so far have used larger cells that are easier to manufacture, but they get around the heat problem by limiting the car's performance and charging characteristics.
The new EVs coming out with better performance but pouch cells might find fast degradation from heat build up. I wonder how the news will treat the first Mission E battery fire? Especially if it happens at a super fast CCS charger. Maybe somebody figured out how to make easily cooled pouch cells?
Chemistry matters a lot. With the right chemistry, the internal resistance is much lower, and heat buildup is less of an issue. You can see this on cheaper EVs, where they can be charged at 2C or even 3C. My 100D is limited to 1.2C.
But these chemistries sacrifice capacity for durability and power. They also use more Cobalt. In my view, Tesla has the right approach.
The Porsche Taycan may be able to charge at 350 kW. But if so, the pack will be significantly heavier and costlier than if it had been limited to 100-150 kW.
But these chemistries sacrifice capacity for durability and power. They also use more Cobalt. In my view, Tesla has the right approach.
The Porsche Taycan may be able to charge at 350 kW. But if so, the pack will be significantly heavier and costlier than if it had been limited to 100-150 kW.
DeBord has never written the sort of hit pieces which Lopez wrote. He's actually been quite reasonable, if not always doing his homework.
Reciprocity
Active Member
Less Cobalt is not a moat. That is silly. It's a very nice advancement, a moat would be something so substantial that no one could hope to counter. Jeff dahn himself said that there are Chinese companies that have 300 phone phds working on battery chemistries. There are solid state batteries in labs that make Tesla's cells look like ancient tech. The issue is that they can't make a billion of them at $100/KWh. The ability to mass produce at low cost is a most that costs many billions of dollars and many years to cross and by the time you do, you will find Tesla's made another moat, distributed gigafactories that made compete vehicles from raw and recycled materials.
Less cobalt is significant, but not a moat. Anyone can and already has, dissected the cells and are working to copy. Is this even patented? Most of the battery vehicles don't use cylindrical, does that make it a moat to?
I like this quote
"Positive word of mouth is the best marketing that there is for an automobile: traditional automakers spend billions annually to engender it."
GM spent 3.1billion in advertising in 2014. The ads I see model positive word of mouth behaviors. That is different than making cars that cause the behavior.
2 and a half years of Tesla R&D?
Tesla Research and Development Expense (Quarterly) (TSLA)
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JRP3
Hyperactive Member
You literally just said that "the issue is that they [Chinese companies] can't make a billion of them at $100/KWh". Yet you don't think that an order-of-magnitude reduction of expensive and hard-to-find cobalt is substantial? I'll clarify -- the moat is Tesla engineering's choices (cylindrical cells vs pouch or solid state), research (Jeff Dahn contributions), and years of advancement in chemistry R&D. And this shows up in the real world -- e.g. the Jaguar iPace that has a 90KWh battery but gets 20% less range than equivalent Tesla pack capacity.
All these other advances you mention are still sitting in labs and who knows when they show up? But Tesla's is in Production today, driving on the roads (parked in my driveway... hmmm... have to go for a drive). Where was I? Oh yeah, it's easy to quantify a lowest-cost mass production moat -- that's what Chinese companies excel at. What is less visible until years later is an engineering and talent moat. I invest in Tesla because I think there's more there than first-mover advantage and they'll continue to be 5 years ahead of everyone else for several years to come.
That's ridiculous. Tesla had to start with cylinders because that was what they could buy. They got good at making packs out of cylinders, so they continued. In particular their knowledge of pack cooling comes from using cylinders.
Tesla uses cylinders because the most commonly purchased battery is the AA. If other companies thought that cylinders gave them an advantage they would be developing packs based on cylinder shaped cells.
No.
It is because grain silos are cylinders.
Same reason Falcon 9 is a cylinder.
AA batteries were originally called Agricultural Activators due to allowing farmers to work at night without risk of fire from lanterns.
AAA were Agricultural Activators Attenuated due to smaller size.
(Or it's due to the optimized surface area to volume ratio along with inherent structurally strength, who can say...)
Choosing cylindrical small cells is not incidental but the result of optimization. This is true back in 2012 and still true today. If you don't believe me you can hear it directly from Straubel.
https://www.quora.com/What-is-the-a...-large-battery-to-power-the-electric-vehicles (scroll down to AK Prashant's answer)
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You haven't posted anything yet to support your assertions, either that other companies have cells that are as capable as Tesla's M3 batteries or that battery chemistry (i.e. total performance profile) matters little to Tesla's total moat against losing it's lead in the next five or more years. So your being 100% sure of an unsupported statement means nothing.
You don't get that Tesla's moat is not one single advantage but the sum of many advantages. I don't think any of the moat advantages are bigger than Tesla already having a GF built, operating and set to expand cell production several times over the next several years.
But that in no way means that other advantages - especially their cells having better performance than those available to other EV manufacturers - are unimportant. Elon and J.B. don't monitor new battery developments as closely as they do, nor fund partners like Jeff Dahl, because cell performance isn't important! Cathode and anode refinements improving per cell energy density are the drivers of continued cost per KWh reductions Tesla is confident enough about to promise range and power for the Semi at an attractive cost.
Building more GFs is critical so fast ramping EV and Storage products are possible. Not that each new GF is going to produce cells for 20, 30 or 40% less cost than GF1 (already optimized due to scale and automation improvements). There will be further production cost reductions moving forward, but they are necessarily slower and more modest than what Elon and JB know is possible with improving batteries 7 - 10% annually.
Pop tarts can have very thin cooling passages between them.
Not clear to me that you don't get film boiling and virtually no cooling when things go wrong. Like being close to the edge, depending on the thickness and forcing function of the cooling channels.
The cooling function may be more robust with the cylindrical cells. Don't have the detail and have not done the simulations.
Not clear to me that you don't get film boiling and virtually no cooling when things go wrong. Like being close to the edge, depending on the thickness and forcing function of the cooling channels.
The cooling function may be more robust with the cylindrical cells. Don't have the detail and have not done the simulations.
JRP3
Hyperactive Member
Something I hadn't considered about the China GF, access to rare earth minerals for the new motors.
Tesla's China Factory Resolves Neodymium Risk To Model 3 Production - Tesla, Inc. (NASDAQ:TSLA) | Seeking Alpha
Tesla's China Factory Resolves Neodymium Risk To Model 3 Production - Tesla, Inc. (NASDAQ:TSLA) | Seeking Alpha
RobStark
Well-Known Member
"Given the environmental implications involved in rare earth mining, I don't believe that it will be all that simple to ramp up production in the rest of the world."
I am 100% sure if the Pentagon were indeed desperate for Neodymium that the Rare Earth Mines along the California Nevada border would be pumping out rare earth minerals within two years. There is wide leeway for POTUS when national security is involved.
And IF nobody outside China could get Neodymium because of trade wars then Tesla outside China could manufacture Model 3 with AC motors. Competitors in markets outside of China would not be able to use permanent magnet motors either.
BTW I stopped reading the article when author said it is unlikely Tesla could sell 500k units per year in 23M units Chinese market that is growing ~5% plus per year.
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