I have seen a Linus Tech Tips video recently on YouTube about battery issues on galaxy devices which is not explainable... not even Samsung can provide any specific information about it. And i'm one of them affected by the same battery sucking ghost issue with my samsung phones since ast 3-4 years. Galaxy S7, Galaxy Note 8 and now Galaxy Note 9. The battery is below average on my "note 9". In idle mode in the night it ***** up around 20% of the battery which is not acceptable. In my test i turned off all the things (wifi, bluetooth, mobile data, AOD, phone was on total silent mode, mail notification is already muted by me long time ago). Still it ***** around 20% of battery.
We apologize for the battery issue facing in the device.Performance of battery depends on various factors; any third party application, software glitches may cause trouble. Kindly follow below mentioned steps to overcome the issue. 1) We recommend you to charge you handset with original wall charger that came with your handset sales pack. 2) Kindly clean the charging point of your charger and battery with a dry and soft cotton cloth to remove unwanted accumulation of dust/waste material. 3) You can also check the charging process while device is in switched off mode. 4) We also suggest you to charge your handset with alternate Samsung Approved charger to exclude the possibility that current charger is not the root cause of failure. 5) Check whether Bluetooth, WI-FI, GPS, Bluetooth, NFC / S Beam, Tethering and Portable Hotspot is turned off when not in use. 6) Check whether the brightness of the device is set to minimum. 7) Smart Features in Flagship phones like Motion UI, Smart Stay, Air Gestures, and Screen Mirroring / Smart view etc. will drain battery considerably. 😎 Check Power Saving Mode (If available) 9) Auto Sync of E-mails, App data etc. will drain battery. 10) Multiple Applications running in back ground will drain battery power. 11) Network Fluctuation also drains battery. 12) Minimizing the back-light time would save battery. 13) Follow the standard charging procedure (i.e. charge a fully discharge battery in Switch-off mode up to 150 minutes.) 14) Periodic Software Update through KIES, FOTA or Smart Tool is intended to improve the battery life as well. • (Setting>>About Device>>Software Update>>Update) update using 4G/3G/ WI-FI connectivity. 15) Check by Go to setting>Application Manager>Running>Stop downloaded application when not in use. 16) After doing the above procedure, kindly restart your device and check the performance. 17) Check the issue in the safe mode. If issue still persists, KIndly provide logs/video within 15 minutes of issue occurrence by registering this feedback via Samsung member application i.e. Samsung member BETA app> BETA feedback>Sendfeedback>Error report>Collect log files>attach. Be sure to hit ? when you find an answer that works for you. For Further assistance, you can get in touch with us via Live Chat option by following- http://livechat.support.samsung.com/Customer_new/IN. You can also connect us via Samsung Members web community by following mentioned url https://community.samsungmembers.com/en_IN#/
Same thing started to happen on my phone as well all of a sudden. I loose 25-30% battery in 7 hours overnight even when power saving mode is on. This wasn't the case a couple of weeks back. I haven't downloaded any new apps either. S10 is around the corner, so let's just queue in to buy the new flagship, since devices sold 3 months back are suddenly slow. Reminds me of Apple, in the worst sort of ways.