View Full Version : powerbook battery

Aug 18, 2005, 04:09 PM
so the census here seems to be that its perfectly fine to leave a powerbook plugged in all the time so long as yuo let the battery drain once a month? i thought you could overcharge li-ion batterys........

Aug 18, 2005, 11:21 PM
The battery will stop charging once it is full. When the pluged the powerbook gets power from the outlet rather than the battery. It will only charge the battery if it is not full.

Aug 19, 2005, 01:57 AM
The battery will naturally slowly drain even if plugged in. The PowerBook will charge the battery back up to 100% once it gets down to 94-95%. It will stop charging at 100%, allowing the battery to slowly drain again, repeat.

The consensus seems to be that the proper way to treat a Li-Ion battery is to fully discharge it and then charge it back up once in a while, however, if you pay close attention, these are the very same people whose batteries last only 60 minutes or less after a year of usage. You can trust them, or you can trust me, whose battery still gets a maximum 4 hours of life after 4 years of almost never being used (PowerBook always plugged into the wall, battery never ever fully discharged).

Aug 19, 2005, 02:25 AM
so yours is always plugged in with the battery and you get 4 hours on it?

Aug 19, 2005, 02:27 AM
Alex_Ant is just messing with you. The best thing to do is bend the tines of a salad fork and try to short-circuit all of the connectors of the battery.

Oop! Time to start another thread on battery life! ;-)

Aug 19, 2005, 02:28 AM
Lithium Ion Batteries like to be used on a steady basis, but they donßt really like complete discharges.

There lifespan is counted in cycles, usually around 300 to 500, depending on the strength of the used cells. One completed cycle is a full drain of the battery. If you drain it only half way through (50%) e.g., itīs half a cycle. When you keep it attached to the outlet, the slow drain of 5 % in a couple of days is 5% of one cycle only.

So if you always drain the battery right to its end, you are alyways using a complete cycle and therefore you shorten the battery life much more than you would be using it in your needs, like one hour here, replug, one hour there, replug.

Keep it plugged in, when you donīt need the mobility, and use it when you need it. Donīt discharge it completely for no reason. You donīt need to recondition LiIon batteries, they donīt like it very much.

Same goes fo the iPod, itīs using the same technology.

mad jew
Aug 19, 2005, 02:28 AM
Apple has made a very useful battery site (http://www.apple.com/batteries/notebooks.html) that you may be interested in. :)

Aug 19, 2005, 02:32 AM
My powerbook battery only holds an hour and a half charge now. :(

Mines usually plugged in but gets completely discharged about 3 times a month.

Aug 19, 2005, 08:41 PM
so yours is always plugged in with the battery and you get 4 hours on it?
When I rarely use it, yes. Of course, being plugged in all the time like I am defeats the whole purpose of having a battery, so you've gotta find the balance that you're happy with.

Aug 19, 2005, 09:16 PM
I use my battery quite frequently, as I go outside and enjoy the fresh air.. etc.

But when I'm doing some photoshopping I keep it plugged in, or I just want to be at my desk, I just keep it plugged in, no problem.

Aug 19, 2005, 10:28 PM
I lug my PB around wherever I go and most of the times I do have an AC socket around and so used to keep it plugged in....was being an ignorant fool without browsing the batt life pages on apple....but the many threads like this made me now use my comp with the battery either at home or when at work and plug it in the other place to charge......

Aug 19, 2005, 11:19 PM
I was wondering for the people who have powerbooks (preferably the latest rev)

How long does your battery last with full brightness? How long does the battery last on the lowest brightness?

Mine only seems to last about 2.5 hours with full brightness and 4.5 hours with the lowest brightness. Usage for me is simply surfing