10 Replies Latest reply: Feb 21, 2012 7:58 AM by Shootist007
StevenThach Level 1 Level 1

Hi guys, i just got my first macbook pro 13inch a week ago and i have calibrated for the first week of using. But the battery always stays at 5hours or even drops to 3hours. Can you guys help me with this problem ? Thanks.

MacBook Pro, Mac OS X (10.7.3)
  • Shootist007 Level 6 Level 6

    It is not a problem.


    One tip your battery is Pre-Calibrated so do not try to do any more calibrations on it. Do NOT let it run down 20%+/- before you recharge it. Never EVER let it run down kto the point it shuts off by itself, IE to Zero.


    The time remaining will change by what you are doing on it. If you aren't doing much it will last longer. If you are doing a lot of stuff it won't last as long.

  • eww Level 9 Level 9

    You don't have a problem, and your battery doesn't need calibration. See this article:




    "Current Apple portable computer batteries are pre-calibrated and do not require the calibration procedure outlined in this article."


    The length of time your machine will run on a charge depends entirely on what you are doing with it and what settings you have selected on it. You can only hope to get close to Apple's published maximum run times if you are doing almost nothing and every energy-saving possibility is maximized. 5-6 hours is as much as anyone gets while actually doing anything useful, and 2-3 is normal when the machine is working very hard and the more powerful discrete GPU is in use.
    What you are seeing is normal.

  • StevenThach Level 1 Level 1

    I was just surfing the Internet and chatting with my friends by using wifi. I did not watch online movie or doing any other stuffs. There is also one problem is that the TIME that my battery last keeps on jumping to different hours such as with 50% it last for 3h hours but then it jumps to 4hours then 2hours and a half...


    Sorry if i made any grammar mistake, i am not really good at English.


    Thank You btw

  • eww Level 9 Level 9

    The estimated time remaining will vary up and down as your computer's activity changes. The projection of remaining time is dependent on what the computer is doing at a given moment. The computer has no way of knowing what you will be doing an hour from now; it estimates your remaining time by assuming your level of activity will remain exactly that same as when the estimate is made until the battery is depleted. This is hardly ever true. For this reason, the estimated time remaining is seldom anything you can rely on. A much more reliable indicator of the battery's charge level is the Percentage readout, and I suggest that you change your settings to show perentage rather than time.


    Every time you view a web page that has Flash content, even an advertisement that's of no interest to you, your computer's energy usage increases dramatically. Flash is a huge energy hog, and because so many web sites use it, it's hard to avoid.


    Again: you don't have a problem.

  • StevenThach Level 1 Level 1

    Ok. I get it now. Thank you for responding.

  • StevenThach Level 1 Level 1

    Another thing which i just noticed yesterday. When i plug in my MBP, it says charged, but with 98% battery. Is it normal or the MBP battery life is decreasing ?


    Thanks for helping



  • Shootist007 Level 6 Level 6

    All new MBPs will not start charging until the % drops below 89-92%. this stops Short Cycle Charging which can have a detrimental effect on the battery.

  • StevenThach Level 1 Level 1

    But a few days ago i checked the iStat Pro. It shows that the battery is 99% and charged, but yesterday it showed 98% and charged. This is normal condition, right ?

  • eww Level 9 Level 9

    Yes. The battery is draining slowly, as all batteries do when they aren't being charged, even if nothing is connected to them at all. Charging will start again when the level falls far enough, as Shootist has written above.

  • Shootist007 Level 6 Level 6

    Yes if I leave my MBP plugged in for a day or so initially it will read 100% then after that day or so it will drop to 99%.


    Run it on the battery until it drops to around 50% and then recharge.


    Honestly you really need to stop worrying about this stuff. If the battery fails in the first year Apple will replace it under warranty.


    Stop watching the dials and start using it.