A:Answer It is never recommended to leave anything plugged in 24/7 once it has been charged to 100%. As soon as it has charged to 100%, do your best to unplug the unit. I have charged the Anker 522 to 100%, unplugged it, and then THREE (3) MONTHS LATER, I found it had 100% of its charge when I turned it on to power up a dead laptop.