swift 3 sf314-43 Does leave battery plugged in when 80% harm the laptop or not?

Shariff

I already set the acer care centre to limit the charging until 80% for keeping battery life cycle. Does my battery harm if i leave the battery when it plugged in and reach 80%??. Some people said that the modern battery is safe that the battery will not charging anymore and the laptop will use the AC power. if this is true, why the battery is always at 80% whereas that battery is not in charging mode? someone explain to me please. I used acer swift 3 sf314-43

Leostat

The lappy just doesnt route power to the battery as much so it stays hovering at 80% it doesnt really "harm it" as all batteries natrually degrade over time, the 80% limit helps reduce the wear as it wears teh battery more topping it to the max capacity over time. But by the time you would notice the degrigation, it shouldnt matter too much anyway as it should be many years out!