7on said:
lol, this is not so much the case anymore where draining it completely can in fact be more harmful to the battery. I leave my Pod plugged in all the time and still get 9 hours after 2 years.
Come to think about it you can't drain laptop batteries completely, since they go to sleep @ around 5%. And waiting for it to waste that 5% might as well take up a day and also will drain the internal backup battery. Try it, put your PB to sleep and pop out the battery - your pb should still be sleeping. I do not know if this battery is rechargeable either since I have heard reports of some people not being able to do this with their PowerBooks.
Read
Apple's Article on laptop batteries- They update it from time to time.
All batteries have a finite number of times that they can be charged. It is nearly impossible to truly completely discharge the batteries on Apple's laptops, as they are "smart" and have a real "memory". The processor inside the battery keeps track on heat, voltage and amperage in and out, load, etc... It keeps track of each full cycle, that is, if you charge and discharge your iBook 25% of the way 4 times, that's 1 full cycle.
Look here for information about your battery:
Finder-->About This Mac-->More Info button->Content->Hardware>Power.
Here you will see the full charging capacity (this will decrease slowly through time), current charge (this will change as you discharge the battery) and the cycle count.
To me, good battery practice is this. I am very mobile and can't/won't plug in when ever it is possible (an etiquette thing). I have two batteries- one that I charge discharge as needed, the second, I only completely cycle (discharge and then full uninterrupted charge.) Both batteries get a complete cycle once a month, needed or not.
Discharging your battery by running the computer until it is forced to sleep is good practice (read Apple's article) Doing this and then forgetting about the battery for a while and not charging it is bad practice. This will completely discharge the battery, beyond what its firmware can protect it from. This should significantly degrade the battery.
You might just think about shutting down the compuer, as the boot time on Mac's is so quick.