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Anthony A

macrumors member
Original poster
I have a 15 inch Mac Book Pro unibody. It's a couple weeks old. When it charges the battery it charges no problem and when finished the battery notification area of the menu bar says 100%. If I leave the lap top plugged in and use it while running off the adaptor the 100% gradually drops to 99 and than 98 and so on even though I am not running off the battery and the laptop is plugged in. It will continue to drop until I unplug the laptop and run off the battery for a while than plug it back in and it will than charge back up to 100%. Than it starts to drop again and the same thing all over. The machine runs great other than this. What is happening here?
 
IIRC it's because if a lithium ion battery isn't cycled it goes bad, so the power management on the MBP (and the MB) lets the battery run down a little bit.

:apple:
 
IIRC it's because if a lithium ion battery isn't cycled it goes bad, so the power management on the MBP (and the MB) lets the battery run down a little bit.

:apple:

Do you have a laptop and does your battery do this? I have never seen this happen on any of my Windows machines.

I read on the Apple web site about a calibration process for batteries which I have never done could that be the cause of this?
 
Maybe. Try calibrating it, if you experience the same problem then there might be something wrong with the battery or computer itself.
 
omg, google.com, i know im one of those people telling you to google, but theres got to be 1000 other threads of people asking if this is normal, you honestly need to lean to search first, but since i know you wont

YES its completely normal, and your windows machines never did this before because os x = win, and apple knows the hardware and can help the battery
 
Do you have a laptop and does your battery do this? I have never seen this happen on any of my Windows machines.

I read on the Apple web site about a calibration process for batteries which I have never done could that be the cause of this?

yes, my MacBook Pro and my old MacBook does/did this all the time. It's normal.
 
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