I’ve had my Steam Deck since last June, and noticed the battery would drop from “full” when plugged in to 95% as soon as I unplugged it. I tied the calibration method Valve recommends, but also realized when I check the Battery Health in desktop mode/settings, it’s at 88%…which does seem odd after just one year? Curious to hear how others’ devices are holding up.
Also I would not give too much about the displayed battery health, it can jump all over the place. My car also thinks that my battery is pretty much dead and disabled auto-start/stop. The battery is as fine as it can be, the charging circuit just does not keep track of the charge very well. As long as you don’t feel your runtime changing significantly I would not worry much about it.