MacBook battery VS iPad battery

Discussion in 'MacBook Pro' started by sotosoul, Mar 3, 2015.

  1. sotosoul, Mar 3, 2015
    Last edited: Mar 3, 2015

    sotosoul macrumors newbie

    Mar 28, 2012
    Hello, people.
    The latest update of coconutBattery can provide information on the batteries of your iOS devices. Doing so, I noticed that the reported capacity of my 4th gen. iPad is higher than the capacity of my late 2013 MBPr 15"!
    iPad: 11560 mAh
    MBPr 15: 8440 mAh I missing something here? Is the iPad's battery really bigger than the MacBook's?

    EDIT: After a brief research, I found out that the units measuring the capacity of batteries are Wh (Watt-hours)
    So, the capacities are 95 Wh (15") and 42,5 Wh (iPad). Almost twice as big.
  2. ha1o2surfer, Mar 3, 2015
    Last edited: Mar 3, 2015

    ha1o2surfer macrumors 6502

    Sep 24, 2013
    that Wh rating is key because the Macbooks Battery is 11.1v (I think) and the iPad is 3.7v I believe. HUGE difference. So yes, you answered your own question sort of. ;)

    If the Macbook supported a battery voltage of 3.7v (which is doesn't just using the Macbook as an example) then it would have to draw almost 4 times as much amperage (at any given load) then if the macbook was using a battery that was supplying 11.1 volts. Here's an easier way to say it..

    Device @ 5 volts draws 2 Amps (10 watts)
    Device @ 2.5 volts draws 4 amps (10 watts)

    So the iPad battery wouldn't last very long.... lol

    Real Numbers:

    Macbook Battery = Macbook Drawing 20 Watts @ 11.1 Volts (1.8 Amps)= Battery life of 3.5 Hours
    iPad Battery = Macbook Drawing 20 watts @ 3.7 Volts (5 amps) = Battery Life of 1.5 Hours

    Amps = Power (volts) / Watts.

    So lets try an iPhone battery lol

    Amps (x) = 3.7volts / 20 watts = (x)5 amps.
    ok so the iPhone battery is 2915 mAh or 11.1wH.

    5000mA / 2915mA = .5. so.. 30 minutes of battery life :)

    Hopefully that fills in the gap!
  3. TheMacNinja macrumors newbie


    Mar 3, 2015
    Albany, NY
    As previous poster alluded to, the "Mah" does not denote the physical size of the battery.

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