so I've long had an issue with my laptop battery, and e.g. in Windows had to figure out how to configure it from the command line to really never emergency shutdown when plugged in, which inexplicably you can't do from the UI

on Linux I knew it didn't last long, although mercifully I didn't have that issue specifically

Today (after buying a replacement battery at no small expense, but not having fitted it yet) I tried an experiment to try to set a baseline to see if the new battery would really be better, so I started up my laptop not plugged in. As usual, the battery charge reported immediately like 3%, and shortly thereafter 0%, where it stayed for two hours of normal usage before the emergency shutdown kicked in.

Obviously two hours is not a great battery life either, but I was expecting like five minutes and probably wouldn't have bothered buying a replacement if I knew it was capable of that. Oh well.