That battery performance really surprising me. My T14 running debian averages ~5-6 hours of coding + browsing. Did you do anything fancy to get those sorts of results.
the t480 has two batteries! one internal and one removable. The laptop using the `tlp` package and a WM like i3wm - which I prefer for functional reasons - discharges at around 5 watts when idle, and running heavy stuff brings it up to 17W max.