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2017 Investor Roundtable:General Discussion

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Those are not full cycles. Only 3.6V to 4.05V? What level of SoC is that? About 50% of overall state of charge? Tesla range charging is up to and I belive over 4.20V and depth reaches down to low 3.x when fully depleted. Show me full cycles, not half cycles.

Test was on 400 mAh cells before the report's 2011 publication. Let us rather see the results of the Tesla spec 3200 mAh cells using 10% to 95% SoC or even range charging levels down to 5% as if someone is travelling.

Actually, on a 60 kWh pack, 3.6 volts corresponds to ~0 miles of range. It is possible to accidentally discharge below that, as kmanauto had done in his 60. But that's driving below 0 miles as presented by the car. The onboard BMS exposes the voltage range of 3.6 volts to 4.2 volts. So it's roughly cycling at 75% to 0% to get ~12% degradation at 3,000 cycles with high temps, charging and discharging at 2C. Driving 75% to 0% and Supercharging at 130 kW over and over again, roughly 125-140 miles at a time (using ~155 miles of rated range) is basically doing Supercharger jumps over and over. These results show that the pack would have 12% degradation after 396,000 miles. And this is a 60 kWh pack. Of course, the lab result doesn't exactly correspond to the real word and YMMV and any particular pack may have weaker cells.

You only mentioned total mileage, not someone range charging each day and driving to depletion, or roughly 180 miles a day. Even then, degradation is really more a function of how long one stays at the highest voltage. It apparently doesn't affect it as much if one range charges and then leaves soon afterwards.

You wanted data, I supplied data from Panasonic's own researchers using NCA chemistry. Whether it is 400 mAh or 3150 mAh, it doesn't matter for life cycle testing... its more about optimization. Even if you took a discount factor, it shows that 2,000 to 3,000 charge cycles is far more likely than 1,000, to 80% using the voltage ranges exposed, especially factoring in use patterns. Very few people range charge every single charge cycle.

Going back to your original surmising, switching to NMC cells for automotive use doesn't make much sense for Tesla given the current state of things since they already did the hard work on the pack design to handle NCA. For someone else, they may not want to sort through such pack design, so using bigger NMC pouch/prismatic cells makes sense to them... it's not like they're trying to win at BEVs yet anyways.
 
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So I'd like to suggest that going forward grids of the world adopt the rule that every MW of new generation capacity be paired with 1 MW and 4 MWh of battery capacity. This is the new rule that all generators be backed up with storage.
Even if that's a great idea it's definitely not going to happen in the time frame of this 2017 thread, or before our J19 LEAPS expire.
 
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I love this:
Tesla is leading a new charge to allow direct sales in Texas with a pure free market approach

When Tesla is trying to push for new legislation to allow its direct sales model in a state that is banning it, the automaker generally tries to ask for an exemption for automakers selling electric vehicles or for automakers that never had third-party dealerships. It attracts less opposition – or justified opposition – from local car dealers.

But that approach didn’t work in Texas so the company is trying a different one. Tesla is now supporting a new legislation in the state to allow all automakers to sell directly, which franchise dealers are already calling the end of the their world.

That way, Tesla cannot be accused of seeking preferential treatment like with their last effort during the previous legislative session.

Senate Bill 2093 and House Bill 4236 have been introduced by state Sen. Bob Hall and state Rep. Jason Isaac is presented as a true free market bill that would allow any automaker to sell cars in the state and bypass the third-party dealership model.

Automakers would be able to compete with dealers for sales and service, but the Texas Au.tomobile Dealers Association is arguing that it would actually “reduce competition”.

President Bill Wolters said in a statement Friday (via Texas Tribune). Tesla’s legislation seeks to unravel the entire franchised dealer system in Texas, in favor of direct sales of motor vehicles by a manufacturer. SB 2093 and the reduced competition it will bring about in the new vehicle sales and service market will come at the expense of Texans and Texas.”
 
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Man, I've got to get to Kauai someday.

Looks like you should plan to stay at The Cliffs at Princeville. If you search for "Solar Update" in their February newsletter, you'll see that they've putting in solar panels backed by PowerWalls, to be completed this spring.
The installation of the roof stanchions (to which the solar panels will attach) is moving according
to schedule. Next the rails and solar panels will be installed. While the roof work is being done, batteries,
inverters and wiring will be installed. When all of the components are in place the wires will be
connected and our solar electric energy production will begin.
 
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Mike Cannon-Brookes tweet to Elon today regarding Elon's effort to help South Australia was solid: "@elonmusk mate, you built the world’s biggest factory & then publicly dropped
1f3a4.svg
on price. Nations are changed w actions not words. Thank you"
 
From the Q1 2015 conference call:
It's well known the Tesla Energy packs use cells with lower energy density. A gen 1 Powerwall used 888 cells for 6.4 kWh, or 7.2 Wh/cell, while a P100D uses 8256 cells for 102.4 kWh, or 12.4 Wh/cell.

The discontinued 10 kWh Powerwall for backup power would have used vehicle cells, and would have had an actual capacity of 888 x 12.4 = 11.0 kWh if it were produced today. (I believe they produced a few 10 kWh Powerwalls - these didn't have the partial silicon anode that the current cells do - instead they used the cells from the original 85 kWh pack. This pack had 81 kWh and 7104 cells, or 11.4 Wh/cell, so the actual capacity of these Powerwalls was 888 x 11.4 = 10.1 kWh.)

The Powerwall 2 likely uses around 960 cells with ~14.5 Wh/cell (and the Powerpack 2 likely uses around 15,360 cells), while the Model 3 likely uses 2500-5000 cells with 18.5-20 Wh/cell.

Now that you've been brought up to speed until around Q1 2015 - do you have any further questions?

Getting up to speed with 2 year old PW1 and PP1 is hardly of any use when Tesla is now on PW2 and PP2, and hasn't disclosed much what they use for the new line of products. Neither is there any disclosure of how many lines operate at GF. I have my doubts, that they are operating two lines for two different chemistries at the low volumes they are running now.

But since your argument is still based on 2015 ER call, please read the article link @dc_h so generously provided (re-linked below). The idea of the grid storage was clearly to stabilize the grid, provide instant power for the rush few seconds. And the expected frequency of that event was 60-70 times a year, leading to ~10-15 years of life time.
Tesla will use different batteries for its grid products. Here's why
Tesla CEO Elon Musk said on the company's earnings call that Tesla will be using a high energy lithium-ion NCA battery for its new grid battery. Similar to the one it uses in its cars, the grid battery is intended for use by utility companies for back-up power. These are the batteries that, when used in a big battery "farm," could replace so-called peaker power plants, the "dirty" and expensive power plants that utilities use only when grid demand peaks, such as during a sweltering summer afternoon. (The Tesla website describes this as the back-up battery with a capacity of 10 kilowatt-hours and a price of $3,500.)
..
The back-up battery is intended to offer a lot of energy, quickly, to smooth out that "heat wave" grid peak without using a peaker plant. It's like when someone driving a Tesla Model S punches the accelerator.

Read that article, and if you have some spec of Powerpack 2, please get back to me. Otherwise, i think this conclusively proves that at the data point we have for 2015, Tesla wanted to use NCA with (optimistic) 1000-1500 cycle lifespan for grid storage.

BTW, if you have any disagreement with the battery university life cycle charts, please ask them to correct those. That will be a favor for everyone. Their NMC chart also doesn't look as good as you and some others are claiming. We don't have the bandwidth or resources to prove or disprove these here. See Table 2 in the link. Even NMC is shown as 300 cycles with 100% DoD, and 1500 cycles with 20% DoD. May be, Elon's quote of 1500 cycle life span was just the upper boudn of optimism, as usual.
How to Prolong Lithium-based Batteries - Battery University

And you chose 1,000 how? Here is a research paper presented by Panasonic employees on cycle testing NCA chemistry:
Development of High Power and Long Life Lithium Secondary Batteries
At 2C with a pretty large voltage window, at 50 degrees C (122 F), degradation is approximately 12% at 3,000 cycles.

The duty cycle in the car can be rougher and easier than this. Tesla's Supercharging isn't as high as 2C and discharge can be much higher. But this kind of cell chemistry does well with higher discharge than charging. And note that NCA really isn't affected nearly as much with higher temps.

This is only a 1 page abstract, without any mention of the depth of discharge, which is very critical in determining the lifespan in cycles. Do you have the full paper or the depth of discharge used in these plots?

PS: One downside of installing the expensive batteries, as in SDG&E and SCE areas in southern California, is that the consumers end up footing the bill. We will hear more complaints from @FredTMC how his cost of charging his Tesla is going up :(
 
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(because... clearly I make bad choices... here I go again...)

But since your argument is still based on 2015 ER call, please read the article link @dc_h so generously provided (re-linked below). The idea of the grid storage was clearly to stabilize the grid, provide instant power for the rush few seconds. And the expected frequency of that event was 60-70 times a year, leading to ~10-15 years of life time.
Tesla will use different batteries for its grid products. Here's why

Tesla CEO Elon Musk said on the company's earnings call that Tesla will be using a high energy lithium-ion NCA battery for its new grid battery. Similar to the one it uses in its cars, the grid battery is intended for use by utility companies for back-up power. These are the batteries that, when used in a big battery "farm," could replace so-called peaker power plants, the "dirty" and expensive power plants that utilities use only when grid demand peaks, such as during a sweltering summer afternoon. (The Tesla website describes this as the back-up battery with a capacity of 10 kilowatt-hours and a price of $3,500.)
..
The back-up battery is intended to offer a lot of energy, quickly, to smooth out that "heat wave" grid peak without using a peaker plant. It's like when someone driving a Tesla Model S punches the accelerator.

Read that article, and if you have some spec of Powerpack 2, please get back to me. Otherwise, i think this conclusively proves that at the data point we have for 2015, Tesla wanted to use NCA with (optimistic) 1000-1500 cycle lifespan for grid storage.

So...

1) That article botches it and simply refers to both as a "grid battery", and then actually tries (but fails) to contrast the two. Note:

Tesla CEO Elon Musk said on the company's earnings call that Tesla will be using a high energy lithium-ion NCA battery for its new grid battery. ...

In contrast, Musk said that Tesla will use a lithium-ion battery with a nickel, manganese, cobalt oxide cathode for its grid battery.

So clearly they are conflating what is being used for what... and so it appears the folks relying on this for their argument (*ahem*) are getting confused.

B) Rather than a second-hand article based on the call, you could instead refer to the actual transcript based on the earning call that I've posted the actual link to, or referred to content from 3 times now in this very thread. Because I am a glutton for punishment, here I go again:

Q1 '15 Earnings Call said:
Yeah, there is two applications which are quite different, one is backup power or peak up (15:59), sort of the equivalent, the only utility scale is like peaker plant, which is a high-energy application and then there's the daily cycler application. There are different chemistries depending upon which one you have. So the backup power chemistry is quite similar to the car, which is like nickel-cobalt-aluminum-cathode, the daily cycling control constituent is nickel-manganese-cobalt, so there's quite a lot of manganese in there and one is meant for call it, maybe, 60 or 70 cycles per year, and the other one is meant for daily deep cycling, so it's 365 cycles a year.

And the daily cycler one, I mean, we expect it to be able to daily cycle for something on the order of 15 years. Actually the warranty period would be a little bit less than that. But we expect it to be something that's in the kind of 5,000 cycle range capability, whereas the high-energy pack is more like around the maybe depending upon on how it's used anywhere from 1,000 cycles to 1,500 cycles. And they have comparable calendar lives, and for the high energy one, it's important to appreciate that this actually has a lot of interest from utilities because utilities have to maintain these things for peaker plants, and like when there's like a sharp increase in usage.

So then having a battery pack that can take out those like very sort of weird sharp peaks. like the heat wave day, you could either have a battery pack which requires basically no maintenance and doesn't require any fuel and it's going to peak shave those really troublesome days or you could have, like, a power plant that requires fuel and maintenance and it's got to be – it's always going to be maintained and it takes time, you can't just start it up in 3 seconds, like you've got to have a little bit of notice. But the high energy pack is actually very economically competitive in those sort of situations.

And then the high cycling pack is really great for – if you've got some sort of wind or solar situation, that's where the high-cycling one is really great on the utility scale. And I should say like the most of our stationary storage sales to be at the utility or heavy industrial scale, it's probably – and just a guess because early days – 5 to 10 times more megawatt hours will be deployed at the utility in heavy industrial scale than at the consumer scale.

III) There are TWO applications. The backup or peak pack is similar to a car: high current, seldom used (occasioanal couple-hour peak shaving scenarios). Then there's the "daily cycler" that's used to offset something like solar (i.e. used every night). So because I'm a swell guy, I have color coded the references to the types of pack chemistries, their "types", and their uses. BLUE is for the NCA "peaker" chemistry with occasional usage, and thus cycle life. RED is for the NMC "daily cycler" chemistry and longer cycle life. Perhaps that will make it easier to follow along.


I shall now accept bets as to if this "gets through" to it's intended audience...
 
So sorry, I confused you with that other value guy, @Value Ev . He's been away ever since the runup from $180 began.

Aww, how nice.
Sorry couldn't post much but we just finished our vacation - being on the internet was just not a priority and not easy from many of the places we went to.

Really happy about the run - the TSLA stock I picked up from the SCTY acquisition has been a windfall i wasn't expecting. But I guess that is what a windfall is. Or should I say a solarfall?
 
Aww, how nice.
Sorry couldn't post much but we just finished our vacation - being on the internet was just not a priority and not easy from many of the places we went to.

Really happy about the run - the TSLA stock I picked up from the SCTY acquisition has been a windfall i wasn't expecting. But I guess that is what a windfall is. Or should I say a solarfall?
If you hook it up to a battery, then you can save your profits... just sayin'
 
Do you have any detailed specifics to find 5000 cycles is the NMC pack's lifecycles? Looking at the warranty outlined for powerwall2 it reads like it is expecting something like 3500-4000 under the warranty. If it really can do 5000 cycles and offer 80% capacity after that, then the warranty would be tiered with less degradation factors.

PowerPack deployment in grid stabilization efforts (frequency response) may do non-daily cycling. Such as only for peak demand reaction (get paid from grid for fast-reaction rates, which is good) which is not every day but during either plant outages or very hot summer afternoon-evenings. Those will not get cycled daily and could have 20+ year lifespans. However, packs that undergo daily full cycling (for TOU cost arbitrage) will be the ones to watch at the CA Walmarts or other locations that will be doing daily cycling. 10 years is a long time and I would suspect that either Tesla is flourishing and able to supply replacement battery components for under $100/kWh or they will be out of business. Both sides of the investment community exist and feel either could occur.

Another way to dissuade locations like California grid usage during peak periods is to post a demand fee on Supercharger stations and users during those peak afternoons in summer just as the grid providers place a higher cost on buyers of electricity during peak windows. Cars should be charged in the morning hours of say 2am to 6am generally (and are). Those using Superchargers during afternoon commutes or distance driving need to participate in grid stability by choosing not to use such a high level of power during such times.

You are off with your assumptions. According to Musk TE products are designed to be able to daily cycle for 15 years, which is actually works out to close to 5,500 cycles, but in the same ER he used 5,000 cycles, and that was the source for my statement. BTW, I am still waiting for @mmd to provide source for his 1,000 cycle number. Since I did not see anything, I have to conclude that it was a completely random number that he just made up. I am wondering what are your thoughts on this random 1,000 cycles number he came up with. :)

Here is the quote from Q1 2015 ER call I was referring to:

And the daily cycler one, I mean, we expect it to be able to daily cycle for something on the order of 15 years. Actually the warranty period would be a little bit less than that. But we expect it to be something that's in the kind of 5,000 cycle range capability, whereas the high-energy pack is more like around the maybe depending upon on how it's used anywhere from 1,000 cycles to 1,500 cycles.

As I will show in my next post, these projections from Elon are conservative, so @Yggdrasill estimate of real life capability for the NCM battery packs of 5,000 to 10,000 is very realistic.
 
Even if that's a great idea it's definitely not going to happen in the time frame of this 2017 thread, or before our J19 LEAPS expire.
We'll see how much of a global battery market will open up this year. One thing that is refreshing is to see how much interest there is from all over the world. Nigeria, Ghana, Viet Nam, Ukraine, India, Pakistan, Chile, Canada, Portugal, Greece, South Africa, Kuwait, New Jersey, and many other countries. They are all wanting to know if Tesla can offer this in their countries. So this really could be a pivotal moment.

My sense is that a new rule for battery backup for all new generation is coming. One way to see this is to recognize that still close to half of new generation capacity around the globe is for natural gas, which is not cheap or abundant in most counties. The move to natural gas is largely to integrate renewables or at least to move toward a cleaner fuel. The gas industry likes to pitch gas as the bridge to renewables.

But gas is only a bridge to batteries. When batteries are abundant and cheap, it is the most sensible way to integrate renewables. So gas will have fulfilled its mission as a bridge. So my new rule is just a way to see how batteries displace gas in new generation capacity.

There is of course a pipeline of gas projects. But $250/kWh is a strong enough price, that it will become increasingly difficult to get new gas plant projects into this pipeline. So it should thin out and end. As we see battery projects displace gas projects we'll no that a new rule is coming into play.

Soon enough for your J19 leaps? Let's hope this new battery market cracks open big enough that it boosts your leaps.
 
We'll see how much of a global battery market will open up this year. One thing that is refreshing is to see how much interest there is from all over the world. Nigeria, Ghana, Viet Nam, Ukraine, India, Pakistan, Chile, Canada, Portugal, Greece, South Africa, Kuwait, New Jersey, and many other countries. They are all wanting to know if Tesla can offer this in their countries. So this really could be a pivotal moment.

Lol!
 
Thanks jhm, mitchji, vgrinshpun and yggsdrasill for your ongoing research into the general market principles, the manufacturing and pricing models for TE and the GF, and the science of battery tech and the trends that Tesla is riding and driving. It will be an interesting year and I'm looking forward to skeptics to find something new that Tesla will fail at in the future. Some of those skeptics have moved on from fretting about how poorly Tesla is at making cars, or finding people to buy them. Today they have no market for batteries and they will die after 3 years anyhow. It is interesting how quotes from Elon and JB carry no weight in the discussion for some and are still the Space and EV charletons that were making fake rockets and building cars they would never mass produce.
Hopefully we will have some good news from SA this week and the news of Elon saving an entire region from black outs will be a big catalyst for this new market.
Next years failure opportunities will include level 5 autonomy, a Tesla semi-trailer, a microbus and the model Y.
 
Regarding the NCA - we all know that Model S and Model X cars use NCA. That means that there could be some interesting times to come when the cars hit 210,000 miles and higher and are within the 8-year warranty period. However, since Tesla does not warrant capacity but only that the battery "works" - you have to wonder if their choice to not warranty capacity is due to the NCA limits?

For high-mileage drivers, they should offer a car pack made with NMC with upcharge. Maybe not the P-models but surely 60s should be offered to allow for the 3500++ cycle count. There are people who buy a car and want to keep it 10 years. I know it's rare around these parts - but these people do exist.

Again, you are off with assumptions.

According to the Panasonic internal testing of NCR18650 cells (p.34 of 43), at 100% depth of discharge (DOD), they are capable of lasting 2,000 cycles with 30% degradation. Based on the performance of battery pack in my car, however, (after almost 3 years 9 months and about 72.5k miles), the real life degradation is only about 3.4% vs. 14% expected based on the Panasonic data. So actual world degradation in my case is running at only 25% of the degradation based 100% DOD testing performed by Panasonic. Based on the above I expect battery pack to easily last for about 500k miles in real life use. This, btw, is also happened to be the number of miles that Elon once mentioned (during one of the visits to Norway) that Model S battery pack was tested internally by Tesla.

Here are my calculations
  1. Total kWh used per the trip counter: 24,965.
  2. Multiply by 1.1 to account for vampire losses and remote heating/cooling - 1.1 x 24965 = 27,461.5
  3. Initial range - 265 miles, current range (100% charge) - 256 miles --> degradation is 3.4%
  4. Initial capacity 81kWh; Capacity after 3.4% degradation - 0.966 x 81 = 78.25kWh; average = 79.62kWh
  5. Calculate cycles of battery used based on energy used from #2 above: 27461.5 / 79.62 = 345; Round up to 350 cycles.
  6. Based on Panasonic test results shown below the real life degradation (3.4%) is only one quarter of the degradation according to expected 14%.
Snap1.png


image.jpeg
 
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I think the proper way to look at demand is net of intermittent wind and solar. Net demand absolutely go below zero, which pretty much proves that there is no real baseload.

That is, base load is actually a misnomer for generation because "load" is demand, not supply. So the notion of base load is the minimum level of demand that must always be produced. If this base load is positive, then there is a proper role for "baswload" generation.

But net demand increasingly goes to zero and below as wind and solar increases. So there is no future for true baseload generation. Without use of storage, I see no future for nuclear.

I never understood the idea of "base load" - I mean if you think about a retirement portfolio, you don't have "base load" investing shares (that cover your daily needs of finances) and "peak demand" shares (that cover that sweet trip to Hawaii to see the Tesla powered island). No, you have broadly diversified portfolio that all contributes to your financial needs.

So for me, a well diversified (i.e. many different renewable sources of power) portfolio in a liquid market (i.e. enough storage capacity and grid interconnectedness) is the ideal way to provide cost effective power to all of us.

So I think the ideas of base load, load following, peaking + grid services will go away and we will have much more of a market / portfolio based approach to power generation where wind / solar / water level forecasts are traded against pump-hydro / battery capacity to match demand instantly.
 
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