How fast is the battery supposed to charge?

Discussion in 'MacBook Pro' started by GamerDad, Apr 2, 2011.

  1. GamerDad macrumors member

    Joined:
    Feb 24, 2011
    #1
    I have a 15" MBP and was down to 30% charge, plugged it in, and using the computer, and up to 60% in 30 minutes... Seems awfully fast to me, not that Im complaining. I did the routine suggested by Apple for battery calibration about 1 week ago, so I'm assuming it is accurate, also the rate of drop is about what I expect - overnight unplugged, with nothing running in the background on sleep it drops from 100% to 95 - 97%.

    I am not thinking there is a problem, just seems awfully fast for a battery charge, and was wondering if this is typical behaviour.
     
  2. SandboxGeneral Moderator

    SandboxGeneral

    Staff Member

    Joined:
    Sep 8, 2010
    Location:
    Orbiting a G-type Main Sequence Star
    #2
    It will charge up rather quickly when really low, then as it gets closer to full charge it slows down until it reaches 100%

    Check this link out: Apple Notebook Battery FAQ
     
  3. onthecouchagain macrumors 604

    onthecouchagain

    Joined:
    Mar 29, 2011
    #3
    I notice quite fast charges on my MBP as well. I think this is normal behavior.
     
  4. dusk007 macrumors 68040

    dusk007

    Joined:
    Dec 5, 2009
    #4
    The overall speed depends on the battery cells their voltage and how many Watt the power supply delivers. If you do hardly anything there is more power that can be put into the battery.
    Usually it is like half the charging time for 80% charge and the last 20% take the remaining half. If you install iStat or something. You will see that it sucks in about 70-80W at first and in the end goes down to around <30W. Considering the 15W the notebook needs to run it is a huge difference. If you run it full speed the power supply cannot even deliver as much the 15" never exceeds 90 something Watt and even takes a little juice from the battery for short spikes. In that case charging probably takes forever. The max voltage and capacity is higher though if your battery heats up.
    If you are in a hurry don't ever bother to charge it fully.
    There are even some super speed charging batteries that use the attribute of Lithium batteries to being able to suck in loads of power at the beginning. I assume they simply never charge to max capacity.
     
  5. GGJstudios macrumors Westmere

    GGJstudios

    Joined:
    May 16, 2008
    #5
    Usually it will consume approximately 1% of battery charge for every hour of sleep.
     

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