After a long time of users asking, Valve has actually added an official Battery Charge Limit setting in the latest Steam Deck Beta update so you no longer need to use third-party tools.
Consider two decreasing lines, one with a slightly lower slope. Now imagine the steeper line starting higher on this graph, eventually the lines will cross and despite starting lower the shallower line will be higher.
80% is 80%, there’s no “80% that will last a lot longer”
I mean, 80% corresponding to X mAh battery capacity. It will stay at that value for much longer.
… do you know how batteries work? Or how they degrade?
Consider two decreasing lines, one with a slightly lower slope. Now imagine the steeper line starting higher on this graph, eventually the lines will cross and despite starting lower the shallower line will be higher.