I have a MacBook Pro (Retina, 15-inch, Early 2013) that I use with an external 4K display so I tend to leave the lid closed and plugged in almost all the time. Since it turns off external display when not plugged in when lid is closed. Someone told me this would ruin the battery slowly and that Li-ion batteries should be discharged to around 10% and then charged to keep them healthy and that this model trickle charges the battery which is bad for it. They suggested a docking station that would cut off the trickle charge.
Is this accurate information? How should I best use this model with an external monitor to not damage the battery?
Best Answer
This questions risks inviting a lot of opinion, so some may vote to close this down.
However, to try and keep this to the facts, I refer you firstly to what Apple has to say about their batteries.
In a nutshell, the key indisputable points are:
Also, the latest research confirms one of the most important determinants of what ruins a battery is time. (You could purchase a brand new MacBook Pro battery and leave it unused in its original packaging for five years and then find it's capacity is nowhere near what it should be when you start using it)
Finally, since you're using your MacBook Pro in clamshell mode, you may find this general info useful.