After downloading the most recent system update for my Galaxy S7, the battery life of my phone is destroyed. I previously got at least 24 hours from a full charge, even with heavy useage. Now I get 3-4 hours from a full charge. I have done nothing different to justify the battery draining, I have tried all the power saving suggestions by Samsung and other forums but nothing has helped. Has anyone else had this problem and is there a solution? I work oncall so I need a well charged phone, but I can literally watch the battery percentage draining each minute! I only bought the phone in January 2017.
Its possible one or more of your downloaded apps have not been fully optimised by the developer for the update yet.
If your battery stats isn't showing what's using the battery then you could put the phone in safe mode which turns off all your downloaded apps and leaves the stock ones alone which can help to determine if an app is causing this situation.
If battery improves then come out of safe mode and start deleting one app at a time until you see an improvement.
Also sometimes after an update if the phone is not performing as it should then it can help to remove left over files from the update.
The first method which does not need a back up performing first is to clear your system cache files. Turn the phone Off and then from a set series of button presses will take you into the System File Cache clear those files.
The second method which does delete your files is a Factory Reset. So perform a back up first.
If that does not help then a Samsung Service Centre or Samsung Experience Store will be able run a diagnostic on it.
To add the phones battery does not have an infinite amount of charge and discharge cycles. The batteries output will decrease over time.
In the Play Store the app phoneinfo will show you your current stats and battery heath %
Current Phone > Samsung Z Fold³ 5G.
Does your battery drain come from "cell standby"? I'm suffering in Oreo a serious battery drain of cell standby. The drain is only when you're using mobile data. I'm not the only one with this problem.
My wife's and my phones suffered from the same problem. Battery drain when phone was idle was really bad. Switching off " VoLTE" option under Settings -- Connections -- Mobile Networks helped a lot. Battery drain in idle is back to normal, but phone still consumes much more energy during use. For example, 40 min of web browsing and few minutes of YouTube on WiFi consumed 10%. This was not the case before recent updates. It seems they messed something up with radios. Hopefully this will get fixed soon.