Is it bad for your macbook to drain out the battery to 0% and let it shut down on it's on?
Is it bad or good for your macbook pro to drain out the battery to 0% and allow it to shut itself down?
MacBook Pro (13-inch Late 2011), Mac OS X (10.7.5)
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If you do it once, nothing will happen, but you must avoid it, because it may damage the battery and decrase the battery life. The best is to charge your Mac when it's still turned on, and charge it until 100%. Then, disconnect it whenever you want, because the MagSafe charger stops charging the battery when it gets to 100%.
If you want more information about Macs and batteries, see > http://www.apple.com/batteries/notebooks.html