Then, that's a function of device's power consumption, which is a function of many factors, which includes user behavior, too. It only makes to sense to talk about it with a particular usage in mind and not in general.
You can have Pinephone suspended for 7 days if you like, under certain circumstances. Or you can drain it 2.5h if you mean to compile Gentoo on it. And completely different SW optimizations would come into play depending on the scenario.
"Battery life" usually means how long will battery last, before you need to replace it.
Typical use for me is to touch my phone (not pp) once every 20 days to put it on the charger and don't toy with it or call at all, just receive an odd SMS or two for 2fa bank access.
If you'll play a game, it will matter whether the game consumes 30% or 290% of CPU time. It will matter if you use the phone mostly indoor, or outdoor, because backlight is a major power sink. It will matter if you need wifi or mobile internet, or whether your usecase is mostly uploading or downloading data, how much screen on time you'll want,...
It's nonsensical to ask for how long will phone run on a single charge without specifying what you'll be doing with it, because it can be anywhere between 7 days and 2-3 hours.
You can have Pinephone suspended for 7 days if you like, under certain circumstances. Or you can drain it 2.5h if you mean to compile Gentoo on it. And completely different SW optimizations would come into play depending on the scenario.
"Battery life" usually means how long will battery last, before you need to replace it.