S21 cell standby draining battery

[mmtech]

I have been observing battery drain for some time and narrowed down to cell standby battery drain as Airplane mode doesn't drain battery. My phone is connected to cell tower that's it. No Internet, no background services, no wifi, stand by mode but still overnight battery drain is 10% in 8 hours. I just have dual physical sim and that was the reason buying Samsung instead of Apple. It looks like Samsung hardware is still not capable to handle cell reception which apple and old basic phones handled very well. Samsung still not improved after so many years and its a battery sucking machine.

Anyone else observed this issue and how to fix it ?

[strawberry cake]

@mmtech 

hello

you may swipe down the screen to open shortcut tray

then tap power saving mode 😉

[BandOfBrothers]

Using two sims in the phone is a known battery resource usage drain @mmtech 

If one or both of your signals are poor then the phone can drain battery trying to remain connected.

[mmtech]

As I said earlier, I already tried all these options but no luck.

[mmtech]

Why this issue is only in Samsung phones.Apple phones works with 2 sims without battery drain?

[GoanGeek]

Totally agree. I Believe OP answered his own question by stating Apple and old phones don't have the issue as they don't support dual sims 😉

[GoanGeek]

Apple is generally more aggressive with background stuff compared to Android in general.
Also it makes it easier for them as they control both software and hardware unlike Android manufacturers.

[mmtech]

Apple supports dual sim with one esim. And there are old feature phones which had dual sims and none of them had such fast battery drain.

[mmtech]

I am just taking here about connecting to network. I know background services drain more battery in Android than ios but this is about basic cell standby feature which should work in all phone properly.

[GoanGeek]

In all fairness . My single sim is around 4 - 5 % battery drain overnight on WiFi and with bedtime mode On.
So with your dual sim seems pretty OK to me.

Then again I mostly charge overnight as I love 100% battery in morning.

Why not try One sim and bedtime mode with each sim separately and maybe you will find which sim is the culprit.