I have a new iBook, the entry level 12" version. I have noticed peculiar behavior concerning the battery charge reading: If I have the iBook plugged into the wall and the battery is fully charged, it reads 100% as expected. If I unplug from the wall and plug into a UPS that is plugged to the wall and turned on (a 2 second maneuver), the battery reading shows 98% or 97% or 99% and it never reaches 100% while plugged in to the UPS (which in turn is plugged into the wall). Has anyone seen this behavior? What is causing it? Is it something to be concerned about? For the record, my iBook battery is not part of the battery recalls. Thanks, -Alberto

Well, to be honest, I have the same thing happen to my laptop regarless of whether it is plugged into the wall, a surge protector, or a UPS. It has to do with the battery calibration. As I write this, my battery is reading 99% and has been plugged in for the last 18 hours to a wall socket. The battery calibration is what causes older batteries to charge to 100% and when you unplug form the wall, they deplete to about 5% in little less than 5 minutes! The 98-100% is nothing to worry about. It is normal. I have noticed that if I completely deplete the battery to 0% and then recharge it, it tends to read 100% for a while... but eventually will start bouncing between 98% and 100%. I believe this also has to do with amount of work your processor is doing. More complex processes tend to use a bit more battery than just letting the computer sit there attached to a socket. Chances are that if you close all of your applications and walk away form the computer for a while, when you come back, the battery will read 100% even if plugged into a UPS. As I said before, this nothing to worry about. It's pretty normal based on the computer's usage. The time to worry is when you get an hour of less battery life when not plugged into anything under normal operating conditions... then you will need to get a new battery.