13687 Views 2 Replies Latest reply: Jan 31, 2008 4:11 AM by First Magus
See this link for general battery information including a description of charge cycles:
Regarding AppleCare and batteries:
Your one-year warranty includes replacement coverage for a defective battery. You can extend your replacement coverage for a defective battery to three years from the date of your notebook purchase with the AppleCare Protection Plan. However, the AppleCare Protection Plan for notebook computers does not cover batteries that have failed or are exhibiting diminished capacity except when the failure or diminished capacity is the result of a manufacturing defect.
Batteries are covered but probably not by your definition. They won't replace a battery dead by 'normal usage' or the likes.
Does anybody know whether Apple will replace defunct batteries under AppleCare?
Yes the cutoff for replacement is usually 300 cycles as Apple states their battery should retain 80% life at 300 cycles.
(what I would consider a defunct battery– my old iBook G3's battery, which holds only 50 minutes of charge.)
Usually an old battery will not retain a charge as good as a new one.
I looked in the System Profiler, and apparently I have already used up 6 charge cycles during the week that I've had my MacBook. What constitutes a complete charge cycle?
A complete charge cycle occurs anytime you run the battery flat an then fully charge it. In other word 100% discharge and charge.
(I'm assuming that less charge cycles are better, and to extend my battery's lifespan, I should keep my MacBook plugged in to power most of the time... Is this assumption correct?)
You would be surprised how many people have trouble understanding this. You are correct. Don't waste your battery for no reason. Below I am giving you the tips to help you get the best life and peroformance from your battery.
It is OK to leave your battery hooked to the charger most of the time. The only time I unhook mine from the charger is when I calibrate or for a few minutes to use in another room. Have you calibrated your battery yet? You should calibrate every two months or so to keep the battery fully functioning. If you use your MacBook infrequently, it’s best to re-calibrate the battery at least once a month.
It is best not to use your battery unless you need to. Some people have hurt their batteries by charging then discharging every time they use the MacBook. This will age a battery very fast and cause you to buy a battery sooner than you should have too. Don't discharge the battery just because you used it. Li-Ion batteries prefer small charges over big ones. Use it and then plug it in as soon as you can. The only time my Battery is ever fully discharged is when I'm doing a calibration.
The following links have good information about the MacBook and the care of it's battery.
Apple: Tips for maximizing your Notebook battery charge
Apple MacBook and MacBook Pro: Reduces processor speed when battery is removed while operating from an A/C adaptor
Apple portable computer's battery does not show a full charge in Mac OS X
Look here and here for some good tips about battery care.
Apple MacBook: How to remove or install the battery
Apple: Determining Battery Cycle Count
Apple: Use and cleaning of MagSafe power connector