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High idle battery drain due to no deep doze

Star III
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.


Star III
Well, apparently we can forget bluetooth playback causing a high drain. I didn't need the phone this afternoon so I did an easy test: play the same 2 hour 30m album on wired headphones, then on my 5.0 bluetooth TWS.
Wired used 3.5% per hour, while bluetooth cause 3.8%, not significantly more.
I guess the jumps to 7-8% per hour I have in the mornings is simply due to the ocassional screen on time.
I will restart the phone to check fresh idle drain. In any case, I suspect it'll settle on about 0.5% per hour (mind you I don't turn anything off overnight, wifi stays connected), and while that's high for 4000mah, I wouldn't be surprised if it's just the SD888.

Star III
So I took a few snapshots this morning after leaving the phone from a fresh restart (only went into GSam to set that moment as the start reference and left the phone alone).
It turns out it does get into deep doze by itself, which is good news, but it doens't make a difference. It did 0.6% per hour over the 8:50 hours. It's definitely high for a 4000 mah battery (about twice as much as I expected when buying the phone, taking into account how clean ZenUI is, and what the Pixel 5 or Xperia phones can do with 4000 mah).
There are no apps running amok (just the usual few short maintenance wakelocks), it's just, I suppose, the combination of how Asus does Android plus the SD888.


Rising Star II
Frankly, 0,5% to 0,6% is quite good.
That's what i have with my Samsung note 9 (4000mAh), and my A42 5G (5000mAh) is at 0,5% too.
PS : my (recent) Zenfone 8 is at 0,4%.

Community Legend I


【Model Name】

ZenFone 8 (ZS590KS)

【Release Date】


Since the server pushes update notice to different serial numbers by batches, it may take some days for you to receive the FOTA notice. Thanks for your patience. You may tap “System updates” in [Settings] >[System] to check if there is new firmware available. Or, you can also try to manually update firmware by referring to the following link.

How to update firmware on my phone?

【Release Note】

  1. Optimized system stability
  2. Optimized fingerprint stability
  3. Improved system power consumption

[210607]ZenFone 8_WW_30.11.51.60
New ota with fingerprint,power consumption and system stability improvements

Star III
FYI here's a screenshot from when I drained to 1% (I don't do that often). As you can see there's a lot of stand by drain (18% + 15.4% mobile network standby). Very light use, no AOD or 2nd SIM, wifi off during night, 60Hz mode in evening/night, ... I'm at around 1%/hour idle drain.