iBook battery weirdness

On the second day after taking possession of my brand new iBook, I calibrated the battery following Apple manual instructions. It settled on 99%, never going to 100%, and the light on the ac cord would turn green, and that was it.... it would never go to 100%, always 99%. No big deal, I figured that's just the way it is. OK, so now it's a couple of weeks later, and just today things are rather different. I was using the iBook on battery, and it went down to something like 50%, amd I then put it to sleep. Later I plugged it in, and it charged up pretty fast... seemingly much faster than usual up to 96%, and then it took like a really long time to charge up to 99%, and here is where it got weird. Usually, when it hit 99%, the ac cord would go green. This time, it stayed amber for at least 40 minutes at 99%. Finally, it went green, and I looked to see the percentage and it was 100% - for the first time! Why would it take 40 minutes to go from 99% to 100%? Then it got stranger... it went back to amber - on 100% charge! It stayed amber for about 10 minutes, and then went green again, still at 100%. Since then, I've had it on ac full time plugged in, and every time I put it to sleep (or rather, I walk away and it goes to sleep), the ac cord light turns amber, I wake it up, and it's showing 100%, then a few minutes later, the cord goes green. And so on. What's going on? I hope my battery is not dying Any ideas? Happens to anyone else?

mad jew said:

Firstly, for future reference the first thing you do with a new laptop is calibrate the battery. Being picky, you probably should have done this on the first day, not the second.

Nevertheless, have you been calibrating it monthly? It'll generally charge to 100% and then cease charging until the capacity falls to 95% whereby it starts charging again. However, 100% is rarely seen and most users see 99% more commonly. This is simply because of the way the individual calibrations are made such that 100% is 100.0 whereas 99% is 99.1-99.9 or so.

As for the strange charging rate, I'd calibrate the battery again and if that doesn't help, then I'd reset the PMU.

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I couldn't have been calibrating it monthly, as I've only had it for less than two weeks. I'll try to reset the PMU. Thanks!