Battery Maintenance

Discussion in 'MacBook Pro' started by BioCore, Jan 1, 2009.

  1. BioCore macrumors regular

    Sep 9, 2007

    I was wondering if doing a full charge and then a discharge is a good thing when a new mac or new battery is bought? Also should it just be a simple charge and discharge or does it have to be a full calibration?

    Also what is the best method in maintaining a healthy battery? Should I cycle at least once a week and do a calibration every few months? Or should one cycle per month be fine? Also is it alright if the battery is fully charged and I have the plug-adaptor plugged in to my macbook pro while using it?

    Finally, is it true that over night the plug or when not in use and not charging the plug should be outside of the macbook pro? Thanks.
  2. iBookG4user macrumors 604


    Jun 27, 2006
    Seattle, WA
    Typically for a normal charge you should stop using the laptop at about 20% remaining or thereabout. I usually calibrate it once a month or so. As for leaving it plugged in for long periods of time, I do that all the time with my MacBook Pro and I haven't seen any adverse effects at all.

    Just make sure that you calibrate it once a month if you plan to use it on the plug all the time. And as for your last question, it's fine to leave the plug in the laptop when it is fully charged or not in use, your laptop is smart enough not to overcharge the battery.
  3. BioCore thread starter macrumors regular

    Sep 9, 2007
    Thanks for the insight. Also thanks for the link jonbravo77.
  4. jcan87 macrumors newbie

    Mar 17, 2010
    You mean that is recommend that always let my computer to 20% then fully charge? that is a normal calibration?

    And for Full calibration you mean completely discharge the battery from 100% to 0%, then leave the battery completely rest for 5 or more hours then charge again to 100%???
  5. Pax macrumors 6502a

    Dec 12, 2003
    I wouldn't get hung up on all this stuff.

    As a previous poster has said, there's no problem leaving it plugged in all the time. the charger is smart enough not to over-charge. After 3-4 hours the charger disconnects the battery and leaves the battery "floating", just like it would be if you unplugged the Mac.

    Read the calibration page carefully:-

    "The battery needs to be recalibrated from time to time to keep the onscreen battery time and percent display accurate and to keep the battery operating at maximum efficiency."

    Calibration is primarily about the accuracy of the on-screen display, and secondly about the "efficiency" which I take to mean ability of the charger to fill it up accurately.

    Calibration is not about extending battery longevity, health, cycles etc. If it was, you could be damn sure Apple would say so to protect themselves from prematurely dead battery lawsuits.

    I have never calibrated my Macbook battery, it's 3+ years old and on 450 cycles, and it is still in very good condition. IMHO calibration is a red herring unless you have real problems with your Mac's battery life, eg you are down to 2 hours or so.

    Just use your Mac. Don't worry about all this battery voodoo. IMHO the real answer is that batteries are like car tyres. Yes, in principle there are things you can do to make them last a tiny amount longer, but those things are so complicated and inconvenient (eg driving only at 50 mph) that it's not worth the hassle.
  6. m85476585 macrumors 65816

    Feb 26, 2008
    Breaking in a new battery is a delicate process that must be done carefully to maximize its life. Here is a detailed step-by-step procedure:

    1. Start using as normal and enjoy.

    If these steps are not followed exactly in this order, the user experience may suffer.

    In my experience, keeping it plugged in all the time will reduce the life of the battery eventually. Keeping it cool (put it to sleep at night) helps, and using it like normal on battery power regularly should help (don't discharge it to a specific point or anything, just use it). Calibrating only calibrates the time remaining indicator, which you probably don't care about if you aren't using the computer on battery. It really isn't necessary to calibrate all that often.

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