Charging stalls at 98%

FrankieTDouglas

macrumors 65832
Original poster
Mar 10, 2005
1,502
2,272
What's up?

I've noticed that in the past couple of days, a full charge on my 15" Powerbook reads as 98% in the upper right. When I bought it back in February, I noticed that half the time, a full charge read as 99% in the upper right. Now it's reading 98%. Is this typical or is there something I can do to set it where it says 100% when the charging is finished? FYI, I'm using 10.3.9.

Thanks.
 

zelmo

macrumors 603
Jul 3, 2004
5,490
1
Mac since 7.5
It's a good idea to occasionally recalibrate your battery. Run off of the battery until your computer is forced into sleep mode, then plug it back in. Your battery should show as charged up to 100% again.
 

jamdr

macrumors 6502a
Jul 20, 2003
659
0
Bay Area
Are you sure this is really happening? Powerbooks won't charge the battery if the charge is already at ~95% or greater. Thus, what happens if you leave it plugged in is you charge your battery to 100%, it slowly starts to lose charge until it hits about 95%, and then will start charging again. It is recommended, though, that you do not charge the battery in such short cycles. It is better to charge to 100%, let it fall to 0%, recharge, repeat, etc. So if you want to make sure your battery is functioning correctly, you should unplug it and use it until the battery is completely discharged (i.e. your computer shuts off and won't turn back on). Then, plug it back in and see if it goes to 100% (it should, but it won't stay there for long so watch it). If it doesn't, I'd say your battery is getting old and won't hold a full charge anymore.
 

andrewfee

macrumors 6502
Aug 29, 2004
467
2
Apple recommends you do a full discharge / charge cycle at least once a month to keep it properly calibrated.

I haven't found any battery drain when it's been plugged into the mains, however what I have found is that if it's 95% or higher, it won't charge when you plug it into the mains. If you let it run off the battery and get to 94% or less and then plug it in, it'll charge up to full capacity. (which I have never seen as being listed at being 100% it's always shown as 99% as far as I can remember)
 

IJ Reilly

macrumors P6
Jul 16, 2002
17,892
1,477
Palookaville
You can re-calibrate the battery, but I wouldn't bother until the full charge was showing at 95% or below if only because full discharges shorten battery life. On my PB, I rarely see a 100% charge. Normal seems to be 98-99%. No harm, no foul.
 

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