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ESS: 53kWh or 56kWh

Discussion in 'Roadster: Technical' started by TEG, Oct 31, 2007.

  1. TEG

    TEG TMC Moderator

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    Does anyone know why Tesla changed their Whitepaper to say the ESS changed capacity from approx 56kWh down to 53kWh?

    Was it for durability reasons?
    Did they change to different batteries, or change the range of charge (voltages ) they allow for the existing batteries?

    That single factor alone would account for the range being (slightly) less than 250 miles per charge rather than (slightly) more than 250 mile per charge...
     
  2. Kardax

    Kardax Member

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    See http://www.teslamotors.com/blog2/?p=48

    "We deliberately chose lithium ion cells with a slightly lower capacity than the largest cells available, because these smaller (and more mature) cells have better long-term durability and higher tolerance for abuse."

    My guess is the original 56k used the higher-capacity-less-durable cells, and 53k represents the ones they're using now.

    -Ryan / Kardax
     
  3. TEG

    TEG TMC Moderator

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    Thanks, Kardax. That blog you point out seemed to be where Martin was pointing out engineering changes that had to happen between EP and VP.

    So does that mean that EPs had 56kWh ESSs, but VPs and production models have 53kWh ESSs?

    The blog you point out was also the first hint that the original range targets weren't going to be met. By extrapolation one could suspect that the range targets were at risk because of the apparent battery change.

    Darryl Siry recently said in the Tesla blogs that "Battery Rumors {are} Untrue"

    It seems the focus there is to say that battery changes didn't cause delays, but could they have caused a domino effect to need to make other engineering changes to try to keep the range from falling too far given less ESS capacity and more weight?

    ---

    Part of the reason I blog so much is that I think it is healthy for Tesla to have ongoing outside activity (unlike a "stale blog" as some other EV makers), and I want to support them, yet these sorts of topics now are possibly things that Tesla would rather think of as "water under the bridge, lets move on" topics.

    So, I am conflicted to keep talking about this, but it appears that reporters have been writing speculative stories about it, so perhaps we need to try to discuss it.

    The other thing that keeps me going is the way Tesla hit the ground running with a very "open" approach with the blogs and information flow. Once they started that ball rolling it is hard to make it stop. Even the reporters seem antsy for the next big revelation, and grasping for straws when the well runs dry.
     
  4. Kardax

    Kardax Member

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    Tesla has really never given clear details about the reasons things change. Our only choice is to speculate :)

    All this drama and confusion during the Tesla Roadster's development is quite educational, in my opinion. It shows how much work and pain is involved transitioning from prototype to production. I can only believe the big automakers have all the same challenges, but they don't generate any press because they have dozens of other vehicles already in production. If Tesla survives long enough, they'll reach this stage too, perhaps post-WhiteStar when they're deciding where to go next.

    If nothing else, any time we see a new EV startup company claim they can be in production in 2 years--when they don't even have a prototype yet--we'll know better :)

    -Ryan / Kardax
     
  5. tonybelding

    tonybelding Active Member

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    I'm sure Tesla unveiled the Roadster to the public much earlier in its development than the big car makers would have, and much sooner than they would have liked. They were under pressure to show something and generate some buzz as an aid to raising capital from investors.

    Tesla have been far more open than any other car maker. Part of that is a deliberate PR strategy, but part of it is also making the best of their circumstances. With WhiteStar and other models that follow, they won't be under the same amount of pressure to unveil early.
     
  6. Kardax

    Kardax Member

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    I'm not so sure. By all indications, Tesla wants to do their IPO next year. To have success with that, they need to generate as much excitement as possible. If they have at least one WhiteStar prototype running around and a couple thousand pre-orders, they'd get 10 times the money that they would if they did it it with only the Roadster out there.

    Post-WhiteStar, as I mentioned above, is when I believe we'll see the big change in Tesla's PR.

    -Ryan / Kardax
     
  7. vfx

    vfx Well-Known Member

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  8. TEG

    TEG TMC Moderator

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    #8 TEG, Nov 1, 2007
    Last edited: Nov 2, 2007
    Yes, I think you guys are probably right. I always got the impression that the Roadster intro was a little "forced" and a bit earlier than they had wanted.

    The big old car companies know better. They keep things secret longer, and have "secret test tracks", and evolved controls to keep insiders quiet.

    Tesla had the problem of having a new product that was extremely exciting to some, and they didn't have a process in place to keep everything under wraps indefinitely. On the other hand, I didn't hear about it until I saw the sneak-peek in "Who Killed the Electric Car", and then the big press intro. I even had a friend or two involved with the project who managed not to say anything about it to me.

    You know, I had been looking with interest at the Wrightspeed X1 until Tesla showed up. Perhaps Tesla was under a little pressure to get the Roadster out so that Ian didn't steal too much of their thunder.

    Well, stay tuned... I think we might be in for some surprises coming up.
     
  9. Cobos

    Cobos S60 owner since 2013

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    What kind of surprises and how soon ? :) Do you know something we don't?

    To reply in kind I can tell that 7-11th of November is Norways largest car-show and Think will be there as well, so there might be someone that can slip something about their new batterydeal. I.e. as in what kind of performance can we expect with any of the new batteries?

    Cobos
     
  10. TEG

    TEG TMC Moderator

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    No, I don't know anything specific.

    Some hints that "something is up" have shown up in some press releases.

    Such as in the article "Tesla Motors may expand plans for assembly plant"

    Where they say:
    "We are in discussions ... about the possibility of more than just an assembly plant."
    ...
    "We are planning on building (cars) in Albuquerque," Eberhard told the newspaper. "It's possible we might want to do something different."
     
  11. vfx

    vfx Well-Known Member

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    I too had info that Tesla tipped their hand earlier than they wanted. You can see by Martin's slide show timeline that the EPs were barely finished when they had the debut in Santa Monica.
    Indeed the EP Roadster's transmission broke that night.

    My brain is fuzzy on what I knew about the "too early" announcement but I get the impression that the EV proponent wolves were sniffing around. I myself sent an Email to Martin about the car in March. (He answered.)

    Don't you think they would have liked to have a few thousand punishing miles -perhaps a VP or two at a debut?


    I also remember asking about secrecy at the party. The Tesla worker said they were driving the car around town with a wrap on it but no one was paying attention. Why would they in Northern California?
     
  12. Cobos

    Cobos S60 owner since 2013

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    Yeah I've seen those as well, just hoping you knew something else/more :)
    I've seen that the Car Show in Lillestrøm I mentioned above has an envorimental theme so there might be something interesting, at least about the 2 Norwegian EV producers? I don't have time myself but there will be a "reporter" from a Norwegian EV forum there so if he discovers something newsworthy I 'll report here as well :)
    I seem to recall there was some speculation that Tesla would bring some Whitestar news at a car show in the very near future, seem to recall it was November, anyone know/remember the specifics or is this just wishfull thinking?

    Cobos
     
  13. Kardax

    Kardax Member

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    I blame "Who Killed the Electric Car?" for forcing Tesla out of hiding. Besides the fact that a Tesla Roadster was in that movie for about 3 seconds, the awareness the film created for EVs presented an opportunity that Tesla couldn't pass up. The timing might not have been ideal, but it worked out for them financially.

    -Ryan / Kardax
     
  14. Kardax

    Kardax Member

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    I don't know where the rumor started, but with the recent Tesla Roadster delay, it seems highly unlikely that any WhiteStars will be seen anytime soon.

    Tesla's VP of Marketing, Darryl Siry, has a very public disdain for EV companies that announce things but never get anything done (ZAP! being an obvious example). I doubt we'll be hearing much about WhiteStar until Tesla Roadster deliveries have started.

    A positive effect is that the WhiteStar will be that much closer to completion when they finally get to show it.

    -Ryan / Kardax
     
  15. TEG

    TEG TMC Moderator

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    #15 TEG, Nov 2, 2007
    Last edited: Dec 12, 2011
    Yeah, reporters are "ragging" on Tesla for not feeding a steady flow of exciting news, but if Tesla has nothing exciting to report this month, then by all means I hope they wait and don't try to say something un-finalized too early.

    When Roadsters finally start getting delivered to customers, we can start asking "when is the 'Who Saved the Electric Car' movie going to premiere?"
    whosavedbanner.jpg

    (Edit: the name was changed to "Revenge of the Electric Car"...)
     

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