Brand New Ibook Battery Won't Charge

September 27, 2007 10:46 AM

My new off-brand battery for my ibook G4 won't charge past 49%. Help!

I just bought a new battery for my 14" ibook G4 from batteryheads.com. As per Apple's instructions, I installed the new battery and left it plugged in overnight, intending to fully charge it and then fully discharge it.

Well, it's been plugged in for almost 12 hours now, and it's still only charged to 49%, according to the computer. All four of green lights on the battery itself are lit, apparently indicating full charge. I have tried restarting the computer and resetting the PMU, but no change.

Should I let it discharge? Will this reduce the battery's power? Do I have a bad battery? Help! I have so much work that needs to get done on upcoming plane flights!

posted by ilyanassa to computers & internet (5 comments total)

You haven't completed the procedure, which is to fully discharge the battery after charging. It's at discharge time that battery calibration is performed.
posted by majick at 10:54 AM on September 27, 2007 [1 favorite]

Reset the PRAM?
posted by mphuie at 11:23 AM on September 27, 2007

majick has it. You need to run your computer off battery only until it warns you that it's running on reserve power -- and then even longer until it puts itself to sleep. At this point, plug it in until it's fully charged. Now your battery percentage indicator should read 100%.
posted by pmbuko at 11:44 AM on September 27, 2007 [1 favorite]

I had this happen to me, and I called the supplier. (I don't recall which supplier, though.) They sent me a replacement (and let me keep the one that only charged to 49%).
posted by Killick at 1:03 PM on September 27, 2007

An hour after posting this, it suddenly went to 100%. I am now discharging the battery. Thanks for your help!
posted by ilyanassa at 3:46 PM on September 27, 2007