When calibrating a battery

Discussion in 'MacBook Pro' started by SeVeN, May 5, 2007.

  1. SeVeN macrumors 6502a

    Joined:
    Aug 8, 2006
    Location:
    San Jose
    #1
    once the battery gets low enough to turn off, cant i just pull out the battery and let it sit for 5 hours? instead of keeping the whole computer shut down. that way i can just plug it in and use it




    "To calibrate the battery:

    1. Plug in the MagSafe power adapter and fully charge the MacBook or MacBook Pro battery until the light on the MagSafe connector changes to green and the Battery icon in the menu bar indicates that the battery is fully charged.
    2. Allow the battery to rest in the fully charged state for two hours or longer. You may use your computer during this time as long as the power adapter is plugged in.
    3. Disconnect the power adapter with the computer on and start using it with battery power. When the battery's charge gets low, you’ll see the low battery warning dialog on the screen.
    4. Continue to keep your computer turned on until it goes to sleep. Save your work and close all applications when the battery's charge gets low and before the computer goes to sleep.
    5. Turn off the computer or allow it to sleep for five hours or longer.
    6. Reconnect the power adapter and leave it connected until the battery is fully charged. You may use your computer during this time."
     
  2. EricNau Moderator emeritus

    EricNau

    Joined:
    Apr 27, 2005
    Location:
    San Francisco, CA
    #2
    After the computer falls asleep, it continues to draw power from the battery to power the RAM.

    By leaving the battery in the computer, you ensure that it is being discharged completely.

    Just plan for that 5 hours to be while you are sleeping. :)
     
  3. SeVeN thread starter macrumors 6502a

    Joined:
    Aug 8, 2006
    Location:
    San Jose
  4. branharrison6 macrumors member

    Joined:
    Mar 22, 2007
    #4
    Is the object of this to leave the macbook in its sleep until it just totally gives out and there isn't even a sleep light indicator?
     
  5. EricNau Moderator emeritus

    EricNau

    Joined:
    Apr 27, 2005
    Location:
    San Francisco, CA
    #5
    Yes, basically, but you should let it sleep for at least 5 hours regardless.
     
  6. View macrumors regular

    Joined:
    Apr 18, 2007
    #6
    I did let it sleep for like 7 hours but the indicator light was still "breathing".... So does that mean I didn't actually finish calibrating the battery then??
     
  7. uaaerospace macrumors 6502

    Joined:
    Feb 15, 2005
    Location:
    Alabama
    #7
    If it was still "breathing," then it won't be 100% calibrated. There is no hurt in what you did, just let it die completely the next time you calibrate the battery.
     
  8. majordude macrumors 68020

    majordude

    Joined:
    Apr 28, 2007
    Location:
    Hootersville
    #8
    As simple as this sounds... I'm confused! :rolleyes:

    In #4 above, let's say I have a DVD in the drive. (I've never let my Mac run the battery all the way down.) I assume at some point it will warn that I am low on batteries. Then, at some point, it will sleep to save a bit of the battery just in case I have an open document or something. Right?

    So I come back and wiggle the mouse or something and it gives me a few minutes to save things and shut it down for good. Right?

    So now I am at #5. I let it sit there sleeping or off (unplugged) overnight.

    Then i charge it and all's well. Right?
     
  9. TraceyS/FL macrumors 68040

    Joined:
    Jan 11, 2007
    Location:
    North Central Florida
    #9
    I have let mine die completely both times - but each time there was a heartbeat for it sleeping.

    The other night i was reading a web page and going to the next when it died on me....

    What else could I do to it??
     
  10. majordude macrumors 68020

    majordude

    Joined:
    Apr 28, 2007
    Location:
    Hootersville
    #10
    Official Information

    From http://docs.info.apple.com/article.html?artnum=86284...

    iBooks and PowerBook G4s other than the PowerBook G4 (15-inch Double-Layer SD)

    1. Plug the power adapter in and fully charge your computer's battery until the battery indicator lights turn off and the adapter plug light goes from amber to green, which indicates that the battery is fully charged.
    2. Disconnect the power adapter and use your iBook or PowerBook. When your battery gets low, you will see the low battery warning dialog on the screen. Continue to use your computer until it goes to sleep. At that point the battery has been sufficiently drained for calibration.
    3. Connect the power adapter and leave it connected until the battery is fully charged again.

    You have to fully charge and then discharge your battery only once to calibrate it. After that, you can connect and disconnect the power adapter when the battery is at any charge level.

    Tip: When the battery reaches "empty", the computer is forced into sleep mode. The battery actually keeps back a reserve beyond "empty", to maintain the computer in sleep for a period of time. Once the battery is truly exhausted, the computer is forced to shut down. At this point, any open files could be lost. Therefore, it is important that you find an electrical outlet and connect the adapter before the forced shutdown occurs.

    PowerBook G4 (15-inch Double-Layer SD), MacBook (all models), MacBook Pro (all models), and MacBook Pro (17-inch) (all models)


    The battery calibration for the PowerBook G4 (15-inch Double-Layer SD) and any model of MacBook or MacBook Pro has been updated because of a new battery released with this computer. With these computers, follow these steps to calibrate your battery:

    1. Plug in the power adapter and fully charge your PowerBook's battery until the light ring or LED on the power adapter plug changes to green and the onscreen meter in the menu bar indicates that the battery is fully charged.
    2. Allow the battery to rest in the fully charged state for at least two hours. You may use your computer during this time as long as the adapter is plugged in.
    3. Disconnect the power adapter with the computer still on and start running the computer off battery power. You may use your computer during this time. When your battery gets low, you will see the low battery warning dialog on the screen.
    4. Continue to keep your computer on until it goes to sleep. Save all your work and close all applications when the battery gets very low, before the computer goes to sleep.
    5. Turn off the computer or allow it to sleep for five hours or more.
    6. Connect the power adapter and leave it connected until the battery is fully charged again.

    Tip: When the battery reaches "empty", the computer is forced into sleep mode. The battery actually keeps back a reserve beyond "empty", to maintain the computer in sleep for a period of time. Once the battery is truly exhausted, the computer is forced to shut down. At this point, with the safe sleep function introduced in the PowerBook G4 (15-inch Double-Layer SD) computers, the computer's memory contents have been saved to the hard drive. When power is restored, the computer returns itself to its pre-sleep state using the safe sleep image on the hard drive.


    There you have it.
     
  11. majordude macrumors 68020

    majordude

    Joined:
    Apr 28, 2007
    Location:
    Hootersville
    #11
    Before and After

    Before and after calibration (with the latest OSX battery update):
     

    Attached Files:

Share This Page