My thinkpad has a mode for keeping a healthy battery that stops charging at 90%, then trickle charges to keep it there (it also allows for fine tuning of this behavior)
I use it on my Samsung given that I don't really need +5 hours without plugging anyway.
As an aside: the mechanism works in slightly different way (at least on all of my 4 thinkpads of different generations). There are two thresholds, maximum battery capacity when charging can start and capacity when charging stops, the aforementioned application even seems to have some kind of logic to set these thresholds according to battery aging.
Also, trying to keep Li-ion cells charged to constant state of charge is not good for their lifespan. What is commonly known as trickle-charging (charging by infrequent, short but large pulses of current) is actively discouraged by most cell manufacturers, sometimes even citing safety reasons.