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Predictions for new battery

edited July 2015 in Model S
Have a look at this data before you make any predictions about larger battery packs:

14 Oct 2010
vimeo t=34:26

Elon Musk: "The need for recharge stations and battery pack swap stations drops with the square of the range because that defines the area you are able to cover. As the range gets bigger and bigger the need for recharge stations drops quite a bit. Arguably if you get to about 500 mile range, you don't need any charge stations apart from the hotel you are staying in because almost nobody drives more than 500 mile a day."

Teo: This shows that 500 mile range is Elon's long term plan. That is why superchargers are free for life because most of them wont be needed in the future. Elon will repeat this 500 mile number many times in following years.

Nov 2012
Youtube time=40m 40:00 to 40:45.
Elon Musk: ... lithium-ion batteries continue to improve. Roughly, on average, maybe 8% or 9% per year. Which, when compounded over several years, ends up being a meaningful improvement.

Feb 2014, Oslo
Youtube time=7m10s
Elon Musk: "There is potential for bigger battery packs in the future but it will probably be maybe next year or something like that."

Mar 2014:
Youtube time=30m06s From 30:06 to 32:20.
Tesla co-founder Marc Tarpenning gave a presentation about Tesla. He talks about battery improvements. If you switch to HD you can see a chart that shows 7.5% improvement per year.

May 2014
Youtube t=5m19s From 5:19 to 8:15.
JB Straubel talked about battery improvements.

Jun 2014
Youtube t=1h6m31s From 1:06:31 to 1:07:28.
At the Annual Shareholder Meeting Elon said the following:
Elon Musk (3 Jun 2014): "You should expect to see a steady increase in range, the available range in the cars over time."

July 2014
youtube t=25m23s25:23 to 27:37.
Tesla Conference Call:
25:23 Journalist: On the Gigafactory, is the chemistry going to be the same battery chemistry that you're currently using or is that part of the discussions that are going on with Panasonic?
25:34 Elon Musk: There are improvements to the chemistry, as well as improvements to the geometry of the cell. So we would expect to see an energy density improvement and of course a significant cost improvement. JB, do you want to add anything?
25:53 JB Straubel: Yeah, that's right. The cathode and anode materials themselves are next generation. We're seeing improvements in the maybe 10% to 15% range on the chemistry itself.
26:09 Elon Musk:Yeah, in terms of energy density.
26:09 JB Straubel: Energy density. And then we're also customizing the cell shape and size to further improve the cost efficiency of the cell and our packaging efficiency.
26:22 Elon Musk: Right. We've done a lot of modeling trying to figure out what's the optimal cell size. And it's really not much. It's not a lot different from where we are right now but we're sort of in the roughly 10% more diameter, maybe 10% more height. But then the cubic function effectively ends up being just from a geometry standpoint probably a third more energy for the cell or maybe 30%. And then the actual energy density per unit mass increases.
27:09 JB Straubel: Yeah. Fundamentally the chemistry of what's inside is what really defines the cost position. It's often debated what shape and size, but at this point we're developing basically what we feel is the optimum shape and size for the best cost efficiency for an automotive cell.
27:25 Elon Musk:Yeah.
27:28 Journalist: The chemical formula will be the same, it's just shaped differently or?
27:32 Elon Musk: No.
27:32 JB Straubel:No.
27:35 Journalist: Is it a different formula?
27:37 Elon Musk: Yeah.

Teo: JB said 10 to 15% improvement in energy density due to improved chemistry. At 10% improvement that would be 1.1*85= 93.5 kWh. At 15%, 1.15*85= 97.75 kWh. Therefore 95 kWh is the most likely size.

21 Jul 2014
Journalist: How far will a battery-powered car be able to go?
Elon Musk: "It will be possible to have a 500-mile range car. In fact we could do it quite soon, but it would increase the price. Over time you could expect to have that kind of range."

Oct 2014
At SoCal Energy Summit JB Straubel used the following image in his presentation.

24 Oct 2014
Elon Musk said "For a cell that doesn't have lots of other drawbacks we are at roughly 300 Wh/kg" 38m 05s: LINK. However, according the following article from 27 Feb 2012, "Model S batteries should weigh in at around 240 Wh/kg" Source: LINK.

Teo: 240 to 300 Wh/kg in 2.5 years is too much. Elon seems to be talking about lab level cells. These are not the 10-15% better Gigafactory cells. These are the cells after that. Here is a calculation:

12% improvement on current cells = 240*1.12= 269 Wh/kg (this is the initial Gigafactory cell)
Another 12% improvement = 269*1.12= 301 Wh/kg (this is next level Gigafactory cell)

Because JB talked specifically about next gen cells at the Gigafactory, his 10-15% energy density improvement statement carries more weight. Therefore I would expect the battery pack to be 95 kWh.

5 November 2014
youtube t=17m25s
Elon talks about Gigafactory cell improvements:

17:28: With respect to the cathode materials, there is a lot of technology improvements that we will be able to apply to the battery pack and the cathode, anode, separator, can production, the whole works. Some of these improvements are independent to others.

17:50: Whatever we build out for the Gigafactory has to work at least at the lab level, let's say this year because we are making monster investments in equipment and there is a certain amount of time, a year or two at least from working at the lab level to working at small scale production. Then at least a year or two after that you can go from small scale production to mass production.

Teo: To me this sounds like Elon is saying the new battery is ready now at lab level but they can't do mass production in 2015 because it needs more time.

7 Nov 2014
Tesla 10-Q Securities and Exchange Commission report had the following information: Source (Page 26)

Quote: Construction continued during the third quarter of 2014 at an accelerated pace with first cells expected to be produced in 2016 for use in Model S and Model X. We plan to use the battery packs manufactured at the Gigafactory for our vehicles, initially for Model S and Model X, and later for our Model 3 vehicle, and stationary storage applications.

This means we know that the Gigafactory will make next gen cells and we also know it will start production in 2016 and additionally we know that those cells will be used in Model S and X.

26 Dec 2014:
Elon tweeted the following:

11 Feb 2015 2014 Q4 Conference Call
youtube t=1h08m32s
1:08:32 Andrea James: If I read through on the range communication on the Roadster 3.0 and I just apply that sort of same range gain to the Model S, I guess I get a 350 mile to 400 mile range Model S by say 2017. Is that the right kind of, I mean, are the gains there translatable?
1:08:57 Elon Musk: It's difficult to put an exact time on it. Like 2017, probably not in 2017. At some point yes. I don't know if that will be ... it's not 2017 but it might be say 2019 or 2020 or something like that. We could make the Model S go 400 miles today, if we wanted to by just increasing the pack size.
1:09:25 Andrea James: Great. I mean at the same cost, same pack cost. Let's say $22,000 pack, will be 400 mile range the next couple of years, but seems that is a bit too aggressive.
1:09:40 Elon Musk: Next couple years is a bit too aggressive. If you go five years out, that might be the case. That's not a prediction, that's just speculation. But I'd say it's not two years but it might be five years.

17 Jul 2015:
Teo: 85 kWh pack was upgraded to 90 kWh. The 90 kWh pack has same number of cells as the 85 kWh pack but the new cells store more energy.

17 Jul 2015: Conference call
youtube time= 8:39
Elon Musk: "We are shifting the cell chemistry for the upgraded pack cell to partially use silicone in the anode. This is just sort of a baby step in the direction of using silicone in the anode. Still primarily synthetic graphite but over time we will be using increasing amounts of silicone in the anode. The physical size of the pack from the outside will look exactly the same."

17 Jul 2015: Blog Post
Elon Musk: "On average, we expect to increase pack capacity by roughly 5% per year."


  • edited November -1
    Elon Musk mentioned an improved chemistry for the 90kWh battery, specifically using a silicon anode. Did anyone see this coming? I don't think the current cells in Tesla's batteries have silicon anodes. Do we have information on how many mAh the cells will hold?
  • edited November -1
    There was talk in 2009 of Panasonic moving from a carbon to silicon anode to enable improvements beyond 4000mAh in 18650s.
  • edited November -1
    I updated the opening message. At the bottom you can see a transcript and link from 17 July 2015 conference call. Elon said:

    <i>Elon Musk: "We are shifting the cell chemistry for the upgraded pack cell to partially use silicone in the anode. This is just sort of a baby step in the direction of using silicone in the anode. Still primarily synthetic graphite but over time we will be using increasing amounts of silicone in the anode. The physical size of the pack from the outside will look exactly the same."</i>

    It looks like using silicone in the anode is a long path that will lead to continuous improvements. From earlier statements lab level testing takes 2 years. They must be already testing the next cells after 90 kWh. That's why Elon says 5% per year because he knows what cells will come after the 90 kWh pack cells.

    The problem with silicone is it affects battery life negatively and there is quicker degradation. They need to find ways to avoid that and do lots of testing. The impression I get is a scenario like this:

    1st gen cells: Roadster cells
    2nd gen cells: Model S 85 kWh cells: soon to be discontinued
    3rd gen cells: 95 kWh cells, already in production
    4th gen cells: 100 kWh cells, about to finish 2 year lab tests
    5th gen cells: 105 kWh cells, just started lab tests
  • edited November -1
    Here is another transcript from the conference call. After Elon said 5% a year another journalist asked this:

    17:30 Journalist: You mentioned that you are expecting a battery pack capacity increase by 5% per year on average. Does that come per year or are you looking at certain spikes like 3 years down the road adding 15%?

    17:49 Elon: I would imagine that it's roughly 5 to 10%. I wouldn't imagine a 15% increase but 5 to 10% every 1 to 2 years.

    <a href= time=17:28</a>

    So we should expect 5% increase in 2016 or 10% increase in 2017 but we should not expect 15% increase. Elon said not 15%. Hopefully this will calm down all the overly optimistic (hello RS) people who have been writing about 105,110,115 kWh packs. That's not going to happen.
  • edited November -1
    I meant to say 105,110,115 kWh is not the next step. Of course it will happen but for the next pack we should expect 95 in 2016 or 100 kWh in 2017.
  • edited November -1
    @ mclary

    I didn't know that there was a broadcast of this announcement on Friday, so I didn't listen to it. I wish that I had known that there was a live broadcast, then I surely would have listened to it.

    Anyway, please stop calling people an idiot.
  • edited November -1
    Silicon != Silicone

    Silicon: metallic element, used in batteries, integrated circuits, etc.

    Silicone: versatile elastomer, used in bathroom caulk, kitchen utensils, etc.

    Listening to Elon, he clearly says "silicon". He knows the difference. If the transcript says "silicone" it's in error.
  • edited November -1
    If you're quoting from the transcript, and it says "silicone", feel free to use [<i>sic</i>] to indicate that the error is not yours.
  • edited November -1
    Thanks for the link Bighorn. 2009, wow. It's fascinating to go back in time, read the announcements, and realize the long lead times it takes to get the battery mass-produced. I know we always hear about different chemistries but if slow and steady is the game then surely we should see an acceleration and critical mass of better chemistries in this decade. Exciting times for EVs indeed.

    @Benz, here's the audio link to the 5/17 press conference:
  • edited November -1
    I'd like to congratulate Teo on a nicely worked initial posted. Good work!

    I know he gets a lot of flak, and is prone to speculate somewhat, but that was a nicely compiled set of data. Interesting and thought provoking.
  • edited November -1

    Okay, I'm the idiot.
  • edited November -1
    I for one am glad I got the old battery. Silicon has been problematic from a cycle life standpoint. Yes it increases capacity but it also has decreased cycle life due to fracting anodes. That's the tradeoff. Perhaps they found a trick to getting there without compromising battery life but I for one am glad I'm not on that early boat right now.

    On the other hand, this chemistry is also much lighter for same or more energy density than the typical carbon based anode type.
  • edited November -1
    Teo, great work. Are you an investigative reporter by trade....?

    If a 500 mile range car may be possible and the ultimate goal of Elon/Tesla, I don't see that reducing the number of people using the chargers. Having a 500 mile range would just enable you to skip more of the chargers. Also by the time there is a 500 mile battery, there will be a lot more Tesla's on the road. So you may have no choice to skip a charger because it is full.
  • edited November -1
    Musk has said that anything beyond 350 miles is diminishing returns, so I think they would rather lower the price than increase the range to 500+.

    If they charge 2K for each Model 3 for supercharging support, that will raise a lot of money to build more superchargers and expand the existing ones.

    And it is possible that if there were enough Teslas on the road, a third party could make their own supercharger that you have to pay for but also get other amenities such as a place to hang out, food, restrooms, and most importantly, access to squeegees. I'd rather pay $25 to charge with no wait than having to wait for a free one. Give people the choice and see what happens.
  • edited November -1

    <i>Quote: Are you an investigative reporter by trade?</i>

    No. I'm just a Tesla fanatic. I have this habit of watching videos while I eat. When I became interested in Tesla I decided Tesla videos were a great choice. So I created a list of all Tesla videos longer than 20 minutes. Then over time I watched each of them many times. Therefore I can easily remember what was said in what video at what point. That's the story.
  • edited November -1
    This is very interesting but here is also some food for thought:

    At what point (range) will Tesla decide that there isn't a need to keep increasing? With the supercharger network growing the way it is and the very real need for EVs to become affordable as quickly as possible, are resources are better spent in things other than increasing range?

    No gas car really needs to be able to go 500 miles on one tank because there are gas stations everywhere. Perhaps it'll take a team of psychologists rather than engineers to figure this one out - what will the masses prefer, longer range or unlimited charging stations? That, of course, would be much easier if someone other than Tesla gets involved in the high speed charging game.
  • edited November -1
    Nice compilation.
  • edited November -1
    <i>No gas car really needs to be able to go 500 miles on one tank because there are gas stations everywhere.</i>

    There are gas stations even in fairly remote locations, such as along Route 50 in Nevada. I would not hold my breath waiting for Superchargers in such locations.

    I can see EVs shouldering more and more of the load, but to really replace ICEs the EVs need to be able to go anywhere, taking a relatively direct route. It seems to me that means either Superchargers in some pretty remote locations, or else a pretty big (range) battery.

    To use another example that someone else posted, even after the 2016 Supercharger build-out you will not be able to go anywhere near directly from Bend OR to Boise ID without a pretty big battery.
  • edited November -1
    @MountainVoyager - Agreed if we're talking Tesla's supercharger network. But what if others got into the high speed EV charging game?
    Think existing companies like GE, Walmart, Gas stations and a pay per kwh model of fast juice.

    These discussions are years, if not decades, too early but once upon a time there were not gas stations everywhere, so it's interesting just to ponder what could be the future state of EVs.
  • edited November -1
    <i>Agreed if we're talking Tesla's supercharger network. But what if others got into the high speed EV charging game?</i>

    What does it cost a rural convenience store to add a gas pump? It seems to me that the only way to get high-speed recharging as ubiquitous as gasoline is for the capital cost of the recharging to be no greater (for a fast DC charge -- slow charging does not count when traveling).

    Until that can happen big batteries are the only solution -- a situation I anticipate will endure for some years to come.
  • edited November -1
    Increased battery pack capacity at higher weight and cost doesn't add much value for the S beyond the 250-300 mile range. It takes about the same time to drive 150 miles and replace the energy used as does to drive 300 miles and replace the energy used because the road time is the same either way but the charging time at 300 miles per stop is more than twice the charging time at each 150 mile stop. This is because the charging rate is nonlinear and really slows down as you try to fully charge the pack from low miles to 300 miles worth as opposed to low miles to 150-200 miles worth.

    Increased battery pack capacity is important for a bigger, heavier vehicle like the MX to get parity with the MS, especially if you want to tow something.

    So, having SCs on every major route about 150 miles apart is probably good enough for the transit time. Destination charging is also important because once you get where you are going, you don't want to have to drive back to the last SC when you need more juice. Lack of destination charging might be a rationale in some cases for a bigger battery pack until destination charging opportunities become more common.

    Recently, we took a trip to Hilton Head, SC and spent 5 days there. There was only one destination charging opportunity that we could find on the entire island at a Hyatt hotel for guests only. Not enough. Maybe we should have tried a Nissan dealer...
  • edited November -1
    I for one would love 500 miles, stopping every 2.2-2.5 hrs on a very long road trip isn't ideal for my family and I'd imagine many others. I hope a TRUE 350 will come sooner than later. Love they keep innovating, hope it doesn't slow down.
  • edited November -1
    I predict that by the time tesla has a 125 battery out Teo will still be a Virgin.
  • edited November -1
    Just a few points that <b>He Whom is Typically Ignored</b> always fails to acknowledge...

    I do not much care about the concept of a <I>'500 mile battery'</I> because I feel that is a misnomer. I care about overall, available capacity. You could get a range of 500 miles in a Tesla Model S 85 today by limiting maximum speed to 65 MPH, and limiting the rate of energy draw below 45 MPH to 150 Wh per mile maximum.

    That would result in a wimpmobile, not a performance car, and no one would buy it. Well, maybe some people would buy it, but they would be idiots. We would be back in the nonperformance dark ages of 0-60 MPH in 12-17 seconds. What a thrill.

    I believe that Tesla Motors intends to always offer performance cars with ever increasing range with each generation of vehicles. So, I look forward to their minimum EPA rated range going from 200 <I>'real world'</I> miles, to 300, to 400 and beyond. All without building any wimpmobiles filled with artificial compromises to range, performance, reliability, durability, or desirability.

    I do not expect this to stop, because the goal is to prove that EVs are better in every way. So, yes... As manufacturing capacities increase at multiple Gigafactories... And energy density improves with new techniques and technologies... And pricing improves due to economies of scale... I foresee that at some point even an affordable electric car will have tremendous capacity that allows in excess of 1,000 miles range at 300 Wh per mile.

    I first saw JB Straubel's chart regarding the doubling of capacity in a video from September 2013. It was a conference at his <i>alma mater</I>, Stanford University. My very optimistic hopes for improvement in capacity are based on his statements during that presentation. In particular, he noted a nearly 40% improvement in energy density per 18650 cell between the introduction of the Tesla Roadster and the Model S.

    I have simply proposed that he may achieve a similar improvement in the time between the introduction of Model S and the release of Model ≡. Thus, the number of battery cells needed to fill an array for a given capacity in 2012 would be less than what was needed in 2007... And the amount for that same capacity would be less in 2017 than it was in 2012.

    Therefore, a 60 kWh battery pack for Model ≡ in 2017 would be considerably less expensive than was offered for Model S 60. Because:
    • If there were ~5,000 battery cells in the 60 kWh battery pack before...
    • Then you might only need ~3000 of the 18650s in a 60 kWh battery pack in 2017.
    • And, switching to a larger format battery cell from the Gigafactory, that holds ~30% more capacity than the 18650 would make for a reduction to only ~2,100 battery cells used in a Model ≡ 60...
    • Thus, the reduction of weight would allow a greater range, and reduction of cost per cell due to economies of scale would make them more affordable.

    Similarly, a Model S could use the same cells, have a ~120-to-135 kWh battery pack that weighed less than the original 60 kWh version, and gain range, performance, and cargo capacity as a result.
  • edited November -1
    @vlad22 - Good thing I wasn't drinking any beverages while reading your post!!!
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