When your laptop’s battery is 100% charged, should you leave it plugged in so any battery power doesn’t get used, or will that cause overcharging, overheating, etc.? Should the laptop be unplugged when the battery level is 100%?
I’m asking because my laptop’s screen tends to get dim when unplugged, so I don’t like to run it on battery.
Solution:
This page has a good answer: “it depends”
The answer is: YES and NO, it depends on the situation.
Having a battery fully charged and the laptop plugged in is not harmful, because as soon as the charge level reaches 100% the battery stops receiving charging energy and this energy is bypassed directly to the power supply system of the laptop.
However there’s a disadvantage in keeping the battery in its socket when the laptop is plugged in, but only if it’s currently suffering from excessive heating caused by the laptop hardware.
So:
In a normal usage, if the laptop doesn’t get to hot (CPU and Hard Disk around 40ºC) the battery should remain in the laptop socket;
In an intensive usage which leads to a large amount of heat produced (i.e. Games) the battery should be removed from the socket in order to prevent unwanted heating.
The heat, among the fact that it has 100% of charge, is the great enemy of the lithium battery and not the plug, as many might think so.