Long Term Downloads

So, Im going on a cruise tomorrow for a week and where I live the internet is really slow, so while me and everyone are away I was hoping I could download a whole lot of games that I purchased, would it be safe to have my macbook pro, (Retina, Late 2013, base model) download while being charged with the screen on screen saver downloading until I come back, or is there another way to download while having the laptop lid close, Im a bit skeptic because my friend had a macbook that he left plugged in for a week without using it and the battery went and now he can't use his mac,

Thank You