I have done the following test:
- Cell charged at 100% at 11.30pm. Went to bed. Next day at 7.30am = Cell had 89% of battery. Wifi and mobile data connected, etc.. the usual.
- Cell charged at 100% at 11.30pm. Enable Airplane mode on and went to bed. Next day at 7.40am = Cell had 99% of battery.
Seems like something related to connection, (I have a dual sim note 9). But this doesnt work for me! I want a phone that behaves normal with the battery drain as it should be and not having to switch to airplane more during the day! I have a dual sim card because I need to be on the phone a lot during the day!
Right now I have 85% of battery life with only 34 minutes of "screen active use"... That means that by 1 hour of active screen use is draining minimum 20%. If I dont touch the phone it can easily go down 7% per hour. I am getting a max of 4.50 min of screen active use per day (standing the phone down to 10% of battery). And that's not normal in this phone, I know it should be around and above 7 hours of screen active use.
I have calibrated the phone baterry, I have restored to factory settings. I have done the wipe cache partition process. I have the "night mode" always on (black screen settings). I deactivated automatic apps update from the playstore, I do them manually. Still all of them up to date at this moment. I have the lowest screen setting switched on (I think is HD+ or so).... I make sure apps are closed. I have deactivated gmail automatic sync.. Only samsung email service every 2 hours or so... I have bluetooh and NFC off... And still draining battery like hell.. And by doing ALL that is that I likely get +4 hours of active screen use at the end of the day... Imagine I wouldnt take into account those steps! And still this seems crazy to me, with my previous phone I didnt have to do all this to have a decent battery life accross the day, plus I switched to this phone expecting "improvement" on this matter and I am getting the opposite.
It is a bug in the modem, for some reason if you let the wifi on , with the data on, the batery drain , just disable the wifi when leave your house and you will see a big difference in the batery endurance
I have a s9 plus and have been using it the same way ever since I got it.
After I installed the one ui update I noticed my battery drain went way up in standby its not about a mistake in a device or something about weak connections its simply the standby.
Before the update my battery ran 4 hours and 45 minutes screen while 13 hours removed from the full charge.
After the update my phone runs 3 hours and 30 minutes at 13 hours after a full charge.
The only way I can get close to my old battery life is by using it straight then it makes it to 4 hours and 30 minutes so its obvious the standby on the one ui is the problem.
I hope samsung finds a way to fix this otherwise they lost a 8 year long user.