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It's the Batteries, Stupid!

Discussion in 'Battery Discussion' started by vfx, May 15, 2008.

  1. vfx

    vfx Well-Known Member

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    #1 vfx, May 15, 2008
    Last edited by a moderator: May 15, 2008
  2. malcolm

    malcolm Active Member

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    "dependence on imported batteries"

    Are there any potential hardline battery exporting nations??? And anyway, what's stopping the US building up it's own manufacturing base. Again?
     
  3. stopcrazypp

    stopcrazypp Well-Known Member

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    That's true, but I think what one of the commenters mentioned is true too, that the battery pack is more like an engine, a part that isn't replaced for the car's lifecycle. Electricity is the fuel. Foreign made batteries are as much a threat to national security as foreign made consumer goods; these things we could always build at home if the situation calls for it, but for resources like oil we really have no choice. Yes it's probably bad for the job market in the US, but it doesn't directly related to security, esp since the countries they listed as primary battery producing nations are Japan and Germany, both strong allies to us.
     
  4. TEG

    TEG TMC Moderator

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    #4 TEG, May 17, 2008
    Last edited: May 17, 2008
  5. WarpedOne

    WarpedOne Supreme Premier

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    #5 WarpedOne, May 17, 2008
    Last edited: May 17, 2008
    Don't forget lithium batteries are recyclable. Thats a major improvement on oil that you can only burn once.
     
  6. Chris H.

    Chris H. Member

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    Lithium is the 33rd most common element in the Earth's crust. There are significant deposits of lithium bearing minerals in South Dakota, North Carolina, and California...
     
    • Funny x 1
  7. david_42

    david_42 Member

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    Another alternative is a fresh approach to lead-acid batteries http://www.fireflyenergy.com/

    Their technology is using carbon fiber mats to replace the support grids for the electrodes. This allows higher power densities for a given battery size, as well as improved charging times, higher energy densities and longer battery life.
     
  8. graham

    graham Active Member

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    Nice little primer on battery technology and who is using what today:

    Market for Electric Vehicle Batteries Is Heating Up - Seeking Alpha
     
  9. TEG

    TEG TMC Moderator

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    I just took this photo comparing 18650 cells (from a flashlight) to more common AA, C and D sizes.

    2996406708_c2137d60eb_o.jpg

    Is that like a bad joke that the Li-Ions are called "UltraFire" with a logo of a burning fire?!
     
  10. doug

    doug Administrator / Head Moderator

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    #10 doug, Nov 2, 2008
    Last edited: Nov 2, 2008
    Thanks, for that. I figure people often make that comparison primarily because the aspect ratio is so similar to that of AAs.
    :eek:

    Someone else worried about lithium:
    Swapping Peak Oil for Peak Lithium? - Future of Lithium Auto Batteries | Hybrid Cars
     
  11. Takumi

    Takumi Member

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    Does anyone know where we can find a timeline of the dominant battery chemistries are?

    Or at least give a rough estimate?
     
  12. TEG

    TEG TMC Moderator

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    #13 TEG, Dec 17, 2008
    Last edited: Dec 17, 2008
    Bill Arnett (Tesla Customer) posted this photos of a real Tesla 18650 next to consumer cells:
    [​IMG]

    Based on the pattern on the positive terminal of the battery, I am guessing Sanyo...
    [​IMG]
    [​IMG]
     
  13. doug

    doug Administrator / Head Moderator

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    #14 doug, Dec 17, 2008
    Last edited: Dec 17, 2008
    What do the Matsushita cells look like?

    The guy from Asahi Shimbun asked me for my best guess as which supplier Tesla uses, and I pulled Matsushita out of my err... hat. I said likely Sanyo or Matsu, but ultimately came down on the side of Panny for no particular reason.




    .
     
  14. dpeilow

    dpeilow Moderator

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  15. dpeilow

    dpeilow Moderator

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    #16 dpeilow, Dec 17, 2008
    Last edited: Dec 18, 2008
  16. doug

    doug Administrator / Head Moderator

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    The photo evidence makes a good case for Sanyo, it seems.
     
  17. malcolm

    malcolm Active Member

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    Thanks David

    Panasonic seem to prefer the "It" symbol instead of C Rate, which



    Looks like it's the same value.

    They seem to recommend 0.7 It for charging http://industrial.panasonic.com/www-data/pdf/ACA4000/ACA4000PE4.pdf

    So for a 2900mAh cell that would be about 4.1 A for about 40 minutes (I think in practice you have to charge in pulses with cell balancing stuff in between)

    Can't find an acceptable discharge rate range.
     
  18. Tim

    Tim Member

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    Yeah, I couldn't find that either, but the discharge curves available in this old PPT http://download.intel.com/idf/us/docs/PS_EBLS003.pdf give pretty good performance, but only list 0.5C and 1C discharge rates. Something of a mystery battery, since other than that Asus, I haven't seen mention of it used anywhere else. Increasing battery capacity has got to be the easiest way to cut weight and increase performance available to Tesla. With prices so much lower than where they were two years ago, its almost a no brainer. And it would help neutralize those "fat elise" comments that the reviewers like throwing around.
     
  19. malcolm

    malcolm Active Member

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    Well I think the Roadster may be stuck with the "fat Elise" taunt. Reducing battery weight would mean re-designing the pack which would require redoing all the crash tests etc etc. When there's Model S and Bluestar (Model T?) to roll out then maybe Tesla will revisit the Roadster if they reach their 25th Anniversary.

    Here's hoping - on both counts.
     

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