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Short-Term TSLA Price Movements - 2016

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I've been trying to find dimensions of the Powerack 1 and compare them to the dimensions of PowerPack 2 ever since PP 2 was introduced. The reason is that such a comparison would allow to ascertain what kind of improvement in chemistry is there in the new GF produced cells.

Finally, Internets cooperated, and I was able to find dimensions and weight info for the PP1 and compare it to the newly published specs for the PP2. The results just blew my mind. Let's just note that the competition is NOT worrying me sick at this point.

PP1 W x D x H: 966mm x 1321mm x 2185mm Weight: 1720kg Energy Capacity: 95 kWh (AC)
PP2 W x D x H: 822mm x 1308mm x 2185mm Weight: 1622kg Energy Capacity: 210 kWh (AC)

So, as a complete surprise and in spite of all speculations that 2-fold increase in capacity was partially attributable to an increase in PP2 dimensions as compared to PP1, the actual dimensions AND weight of PP2 are LESS than PP1.

Here is my hypothesis on what it means to the improvements in chemistry for the GF produced cells:
  • Due to improvements in cooling architecture (I keep promising to post my research on the subject for a while, but life events conspired against it - will try to get to posting it over this weekend), the same quantity of 2170 cells as there were 18650 cells in each pod. This allowed for an increase in energy capacity of each pod by (70 x 21^2) / (65 x 18^2) = 46.58%

  • PP2 has the same quantity of pods as PP1 - 16

  • Since energy capacity of PP2 increased by a factor of 210 / 95 = 2.21, the new cell chemistry improvement is responsible for at least 2.21 / 1.4658 = 50.77% improvement in volumetric and gravimetric energy density (neglecting slight reductions in dimensions and weight of PP2)

  • We do not know whether materials in the new chemistry cells are more expensive than in the 18650 cells, but it appears that there will be very significant cell level cost reduction due to chemistry improvement on top of the at least 30% reduction due to economy of scale. It looks like 2018 pack level cost of below $100/kWh for TE products is a given.
Let's see how long it will take Electrek, Teslarati, et al. to pick up information in this post. :)
I'm not so sure the amount of cells is unchanged. The new PW2 battery pack seems to be roughly 700 x 700 mm. With ideal cell packing, 90.69% of the 490,000 mm^2 area will be filled by the area of the cells.

A 21-70 cell has an area of 346 mm^2, so that means the absolute maximum number of cells is 1284. This means that every cell is touching six other cells. If we assume there's a 2 mm gap between each cell, each cell occupies 491 mm, and the maximum number of cells is 905.

The previous powerwall had 888 cells. So, okay, it's plausible, given a pretty ideal arrangement of cells.

Looking at the active material, the 21-70s should have roughly 1 - (69 x pi x 10^2) / (64 x pi x 8.5^2) = 49.3% more active material per cell than the 18650s. So, if the number of cells was identical, we would expect an improvement of around 49.3%, with no improvement due to chemistry.

And we also know the P100D is using the new pack architecture. Here, the improvement was something like 1 - 100 / 85 = 17.7%. If we assume the improvement due to length comes on top of this, the total improvement due to the pack architecture and cell format should be 1 - (100 / 85) x (69 / 64) = 26.9%
 
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I'm not so sure the amount of cells is unchanged. The new PW2 battery pack seems to be roughly 700 x 700 mm. With ideal cell packing, 90.69% of the 490,000 mm^2 area will be filled by the area of the cells.

A 21-70 cell has an area of 346 mm^2, so that means the absolute maximum number of cells is 1284. This means that every cell is touching six other cells. If we assume there's a 2 mm gap between each cell, each cell occupies 491 mm, and the maximum number of cells is 905.

The previous powerwall had 888 cells. So, okay, it's plausible, given a pretty ideal arrangement of cells.

Looking at the active material, the 21-70s should have roughly 1 - (69 x pi x 10^2) / (64 x pi x 8.5^2) = 49.3% more active material per cell than the 18650s. So, if the number of cells was identical, we would expect an improvement of around 49.3%, with no improvement due to chemistry.

And we also know the P100D is using the new pack architecture. Here, the improvement was something like 1 - 100 / 85 = 17.7%. If we assume the improvement due to length comes on top of this, the total improvement due to the pack architecture and cell format should be 1 - (100 / 85) x (69 / 64) = 26.9%
I was posting early in the morning and I was in a rush, so the above post wasn't quite finished. I edited it a bit to correct some errors. I think I am pretty much in agreement with vgrinshpun, there really should be a substantial improvement in chemistry involved.

I think there must be an increase in the number of cells, and with this amount of cells, really the only way to do cooling is immersion cooling, where you fill the entire pack with a liquid that you circulate and actively cool. The question is, how many cells are we talking about? I think the possible range is 888-1284 cells.

With 888 cells, the improvement in chemistry should be 1 - (13.5/6.4) / ((888/888) x 1.493) = 41.3%.

With 1284 cells, the improvement in chemistry should be 1 - (13.5/6.4) / ((1284/888) x 1.493) = -2.3%

Maybe the highest cell-density scenario that has any realism is 1 mm spacing between the cells. This allows for at least some coolant flow between the cells, and the cells shouldn't touch if the pack is flexed. With this spacing, each cell takes up 380.1 mm^2, and you can stuff in 1169 cells. The closest logical architecture being 12s97p, or 1164 cells.

With 1164 cells, the improvement in chemistry should be 1 - (13.5/6.4) / ((1164/888) x 1.493) = 7.8%

Okay, so my guess is a chemistry improvement in the 7.8-41.3% area.
 
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I was posting early in the morning and I was in a rush, so the above post wasn't quite finished. I edited it a bit to correct some errors. I think I am pretty much in agreement with vgrinshpun, there really should be a substantial improvement in chemistry involved.

I think there must be an increase in the number of cells, and with this amount of cells, really the only way to do cooling is immersion cooling, where you fill the entire pack with a liquid that you circulate and actively cool. The question is, how many cells are we talking about? I think the possible range is 888-1284 cells.

With 888 cells, the improvement in chemistry should be 1 - (13.5/6.4) / ((888/888) x 1.493) = 41.3%.

With 1284 cells, the improvement in chemistry should be 1 - (13.5/6.4) / ((1284/888) x 1.493) = -2.3%

Maybe the highest cell-density scenario that has any realism is 1 mm spacing between the cells. This allows for at least some coolant flow between the cells, and the cells shouldn't touch if the pack is flexed. With this spacing, each cell takes up 380.1 mm^2, and you can stuff in 1169 cells. The closest logical architecture being 12s97p, or 1164 cells.

With 1164 cells, the improvement in chemistry should be 1 - (13.5/6.4) / ((1164/888) x 1.493) = 7.8%

Okay, so my guess is a chemistry improvement in the 7.8-41.3% area.
You can also look at the weight. Assuming each cell weighs 75 grams, 1164 cells would weigh 87.3 kg. The cell weight for a Powerpack would be 1394 kg. That's a pretty substantial chunk out of the 1622 kg official weight.

One additional thing that can be easily estimated is the amount of coolant. With 1164 cells, it would be 6 liters per pod, maybe 7 liters including reservoir. That would add at least 100 kg to a Powerpack.

So, cells and coolant would leave around 130 kg for everything else. I think that's implausible, to say the least. This indicates that the improvement in chemistry is likely substantially greater than 7.8%.
 
The new battery pack cooling is not immersion.
What do you base that on?

It is possible that they have gone with something else, but I think it's the simplest solution. It allows for a relatively simple design with high energy density that's easy to manufacture. You also have very good cooling properties, and with a non-flammable coolant it could be quite fire-resistant. It also fits without assuming huge improvements in chemistry. At my top end estimate of 41% improvement in chemistry, the NMC chemistry would be at only a slight disadvantage to the NCA chemistry. Yet even with that amount of improvement in chemistry, the cells are packed so tight that non-immersion cooling will be very difficult.
 
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Hey everyone, can we talk about this? It appears Tesla has been working on this for a while. It seems to be the main news for today other than election results later on.

techcrunch.com (again) with some interesting insides

Tesla acquires Grohmann engineering to boost production

We thought it was important that Tesla become, in part, a German company,” Musk said, regarding the investment in the country. “That’s what this was all about.”

Tesla CTO JB Straubel explained that Tesla has been working with Grohmann in a partnership for the past few months, and found that the teams complemented each other well and were achieving a lot in terms of automation improvements, and determined they could do even more as a combined company.
 
What do you base that on?

It is possible that they have gone with something else, but I think it's the simplest solution. It allows for a relatively simple design with high energy density that's easy to manufacture. You also have very good cooling properties, and with a non-flammable coolant it could be quite fire-resistant. It also fits without assuming huge improvements in chemistry. At my top end estimate of 41% improvement in chemistry, the NMC chemistry would be at only a slight disadvantage to the NCA chemistry. Yet even with that amount of improvement in chemistry, the cells are packed so tight that non-immersion cooling will be very difficult.

My research of publically available information, which I was planning to share for a while, but did not get to it. It is nearly certain that they've done "something else".
 
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My research of publically available information, which I was planning to share fro a while, but did not get to it. It is nearly certain that they've done "something else".
When you get around to it, we can discuss it further.

I'd like to know how much and how it's being financed.
I agree. Fair value is maybe something like 250 million USD?

I'm thinking it shouldn't have a huge impact on finances, and may also be counted into the planned Model 3 capex.
 
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It can.

If 40% improvement in chemistry is real, that means Tesla/Panasonic has a *huge* technological lead. It means that the competition isn't even in the same ballpark.

It also demonstrates that belief held by many that competition is about to close in while plausible in general terms (and that's how discussions on this topic are always framed), upon closer examination of specifics just does not add up. It is not to say that market valuation can't be based on incorrect perception that competition is about to crash the party, but it is totally different argument than saying that competition has realistic chance to catch up knowing what we know now and the history of more than a decade.
 
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techcrunch.com (again) with some interesting insides

Tesla acquires Grohmann engineering to boost production

We thought it was important that Tesla become, in part, a German company,” Musk said, regarding the investment in the country. “That’s what this was all about.”

Tesla CTO JB Straubel explained that Tesla has been working with Grohmann in a partnership for the past few months, and found that the teams complemented each other well and were achieving a lot in terms of automation improvements, and determined they could do even more as a combined company.

Seem like Tesla will become a company that helps others to build the machine that builds the machine ...
Tesla acquires a German automation company to accelerate vehicle production

Grohmann works with a number of other automotive manufacturers, as well as semiconductor and life-science companies, and the company will continue to work with outside clients, including those in the automotive industry.
 
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