Flakey battery on PB_G4-17

Question

My powerbook's battery is not functioning correctly. Unplugged, it will get halfway started up before running out of power. Started on AC, and unplugged, it will run about 2 minutes, then die instantly. All the while, the battery has 5 button lights that light, indicating a full charge. All the PMU resetting articles I can find ask for a dead battery to start recharging when the PMU Reset is finished. I can't seem to find any way to get this one discharged enough for that to work. Any suggestions?

Answer 1

I don't think you can salvage it. The battery in my 2003-vintage PpwerBook in the original, shows only 130 cycles, and a health of about 85 percent. However, it can only run the computer until it hits about 60 percent charge and then dies. A guy at an Apple Store looked at it and said that, when the "dies" point is roughly the same percentage each time, it typically indicates a bad cell.
He did offer this longshot procedure in a case like mine: after the computer shuts down, recharge while watching the percent meter and let the new charge reach about half of the shut-down percent--in my case, that would be 60/2 or 30 percent. Let the battery run down again, then charge to 10 percent more, 40 in my case. Do this until yu have charges well past the old "die" point.
He explained that, rather than die, a cell can "forget" its state and the above procedure can sometimes "wake up" the cell and get it back to the party. Didn't work on mine, unfortunately. The previous owner ran the PB on wall power nearly all the time which doesn't help battery performance.
Also make sure your ac adaptor is putting out 65W. The adaptor that came with mine is for a 15" PB and only puts out 45W. It cannot start the computer unless the flaky battery is installed.