How do I properly care for my battery on my mac. If my macbook is fully charged does it hurt to leave it plugged in? Will this "over charge" the battery? Whats the lowest I should let the battery get before plugging it back in? the reason I ask is, I have a 2 week old Macbook and I already have 21 cycles and my battery capacity is 89%....... It would seem I am doing something wrong. My current method is to unplug it as soon as the charger gives me the green light. But I just realized this is causing it to go through a "cycle" everytime. So is that worse or better for it than leaving it plugged in even if its fully charged. Thanks.