Brand New MBP, calibrated battery, maximum: 6800mAh????

Discussion in 'MacBook Pro' started by MacDannny, Apr 28, 2010.

  1. MacDannny macrumors member

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    Jan 19, 2010
    #1
    is this for real? I have just calibrated my battery, and it says the maximum battery capacity is 6800mAh (results from coconut battery and sys profiler). ive got a 16 month old 17inch MBP next to me which still has 12500mAh.

    also, my battery has gone down 7% in 12 minutes!
     
  2. miles01110 macrumors Core

    miles01110

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    #2
    What does this:

    ...have to do with this:

    ??

    Capacity and charge remaining are different things.
     
  3. keantan macrumors regular

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    Penang, Malaysia
    #3
    I'm using istat menus 3, which shows the batt capacity as well. I'm getting 6900mAh from my newly arrived, but uncalibrated (calibrating it as we speak) macbook pro 15"

    Is that a normal size?
     
  4. MacDannny thread starter macrumors member

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    Jan 19, 2010
    #4
    yea, but one kind of indicates the other ;)

    i dont think so, because ive got last years 17inch 2.66ghz macbook pro and thats got a capacity of around double that!
     
  5. miles01110 macrumors Core

    miles01110

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    #5
    Not really...
     
  6. MacDannny thread starter macrumors member

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    Jan 19, 2010
    #6
    so a larger capacity battery wouldnt last longer? OK then... :rolleyes:
     
  7. miles01110 macrumors Core

    miles01110

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    #7
    The misunderstanding is due to your poorly-worded original post which I still can't figure out. Whether or not a larger capacity battery will last longer has nothing to do with why your charge decreased by 7% over 12 minutes. Further clouding the situation, you randomly give statistics for a different machine that also seems superfluous.

    What are you actually trying to ask?
     
  8. MacDannny thread starter macrumors member

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    Jan 19, 2010
    #8
    ok i see. well the indicator says it has 4 hours 30 remaining. 7% in 12 minutes is obviously fast consumption, yes?
     
  9. miles01110 macrumors Core

    miles01110

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    #9
    Depends on what your computer is doing. Open Activity Monitor (in /Applications/Utilities), select "All processes", and sort by the CPU column. Is something hogging CPU?
     
  10. MacDannny thread starter macrumors member

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    Jan 19, 2010
    #11
    thanks, just checked, it says the highest usage is from finder, at 2.5%. ive only got safari and itunes open.
     
  11. Wehrwolf macrumors 6502

    Wehrwolf

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    May 21, 2009
    #12
    The maximum battery capacity reported to you by CoconutBattery or System Profiler fluctuates so much, looking at that value on any given day is meaningless.

    You can seem that on my own machine, it too started out at around 6800mAh. Following calibration and regular use over the past week, it's actually gone up, and I fully expect it bounce up and down from hereon out.
     

    Attached Files:

  12. sulhaq macrumors regular

    sulhaq

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    Jul 29, 2006
    #13
    My 17'' i7 says Maximum Capacity @ 12934 mAh. You didn't indicate whether your new macbook is 15 or 17. If it is indeed 17 you may have a lemon.
     
  13. Moriarty macrumors 6502

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    Feb 3, 2008
    #14
    Physics nerd reporting in here :p.

    mAh = milli-amp-hour. A measure of the current the battery will be able to provide at it's operating voltage for one hour. ie, a 6800 mAh battery will provide 6.8 A of current at its particular voltage for a time of one hour.

    What you really should be concerned about is the capacity of the battery in WATT-hours, this measures the capacity irrespective of voltage. What could easily happen is that the newer computers have batteries that supply current at a higher voltage (and because P=(V^2)I, a battery of the same capacity but a lower current will require a higher voltage to compensate). The newer models of Macbook Pros use a different battery layout with flat rather than cylindrical cells, and I wouldn't be surprised if there are more cells than the older batteries. More cells = higher supplied voltage. Though that is just me hypothesising, Apple don't exactly make that sort of info public.

    Best thing to do is just leave your computer idle with display on 50% brightness, doing nothing but browsing light (ie no flash) websites. If you get the 8-9 hours or whatever that Apple claim, your battery is fine.
     
  14. joshwithachance macrumors 68000

    joshwithachance

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    Dec 11, 2009
    #15
    my uncharged, fresh out of the box MBP shows 5900mah as the max, is that bad?
     

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