There's plenty of people reporting a higher than expected battery drain on the Zenfone 8, and while we just have to assume the cost of using an 888 snapdragon, there seems to be an issue with the system itself, causing a high idle battery drain. The phone just never gets into deep doze, no matter how much times it spends turned off. This causes maybe twice the battery drain what it should use while doing nothing. I'm confident in this being an issue with ZenUI itself, since no amount of wakelocks from apps would cause a literal 0 seconds of deep doze, plus I see no wakelocks or strange behaviour from any apps in either the system battery information or GSam Battery Monitor (an app that's always worked well for me in this regard). I'm uploading to snapshots from GSam, one from the Zenfone that I just took after leaving the phone alone for 2 and a half hours, and one from my old s10e for comparison. As you can see, the Zenfone just doens't ever enter deep doze, leading, as of this moment, to a 0.7% per hour battery drain while doing nothing, a drain that's easily twice as high as it should be with a 4000 mah battery (for reference the s10e drains about 0.4-0.5% per hour with an older 3000 mah battery) If we could get a way of fixing this, it'd go a long way to stretch the battery use of the phone.
I already explained I use GSam battery monitor for that, and there are no significant wakelocks at all (over the years I've tuned down my idle drain significantly). It has to be a ZenUI thing. In any case I think I'll just rely on Naptime to force doze faster than stock, seems like a good solution if it doens't cause problems.
Well, just to keep track of this, on the first night with deep doze the drain got down to 0.5% per hour. For a 4000 mah, it's honestly just too much. Let's take into account that's as low as my s10e got, as I said before, with an old 3000 mah battery (and the bloated OneUI, while we're at it, not that it should affect deep doze much). Also, in any case, even though I have the CPU and GPU set at minimum performance in the battery settings (cause I don't need the power), and 90hz on the displaym, with screen on, while only reading, battery drops quite fast. All of this is to say that, although I'm really quite liking the rest of the phone, and particularly ZenUI, the battery performance is quite bad for supposedly 4000 mah (4000 that are lasting shorter than phones I've seen with 3000. Hell, my old Pixel 3a did better)