Hey arfrederick25....Welcome to Android Central Forums.....truly its very frustrating when your device dries up so quickly...I faced the same issue with a HTC phone..having it used for a while and then couldn't make a use of it wasn't making a lot of difference than not having it at all.....I had to keep a basic retro backup phone with the keypads...that was really of better use during those times...
Unfortunately the battery management and specifically the memory management stand really poor..
I am specifying some workarounds ….hope it would help you a bit…
-Factory Reset the Galaxy S6..
WARNING--AFTER BACKING UP ALL YOUR DATA FOR SURE…!!(As this might give us a clean and fresh head start) A hard rest is recommended..
HOW TO..?? (JUST IF YOU DON’T KNOW)
1-First, turn off the phone by using the Power button.
2-Now press and hold together: Volume Up + Home + Power button, until you see Samsung logo.
3-Then select from Recovery Mode menu "wipe data / factory reset" using Volume buttons to navigate and Power button to confirm.
4. Choose "Yes -- delete all user data" to confirm the whole operation.
5. After that select option "reboot system now".
Now some other ways to enhance battery life..!!
-Disable or uninstall any app you aren’t using regularly as it’s a good idea for general performance and increased battery life
-Facebook and Facebook Messenger are known memory hogs. If you can live without them, it will probably make a discernible difference…ifff…!!
-Use a different launcher. TouchWiz is okay.. but it can still be pretty demanding. The Google Now Launcher or the Nova Launcher might help.
-The 2,550mAh-rated battery in the Galaxy S6 is not the biggest battery out there .The phone is quick to charge, but quick to drain as well, and not making it through the day without re-juicing it. The fact that there’s no removable battery makes this worse.
-If you think an app is draining more battery life than it should be, try reinstalling it to see if that corrects the issue. If the problem persists, try uninstalling it to see if was really effecting your overall Galaxy S6 battery life.
-If you can’t figure out which app might be causing trouble, you’ll want to boot the Galaxy S6 into Safe Mode in an effort to single out potential troublemakers. Booting the device into Safe Mode disables third-party apps and allows you to isolate apps that could be causing the problems.
-Restart the Samsung Galaxy S6
-Disable Unnecessary Services both background and at start up…
-Turn off radio communications when not needed:
Disabling features when they aren’t in use tends to have a positive impact on overall battery life. Shutting off Wi-Fi connectivity , Bluetooth , NFC , GPS , and cellular data when you don’t need it.- Poor cellular coverage is often to blame for bad Android battery life. When your phone needs to search hard for a signal, it runs the battery down faster. Keep that in mind when you’re in spotty areas. You may need to turn on Airplane mode when there isn’t a strong 4G or LTE signal in the area.
-Start Using a Black Wallpaper as AMOLED screen would help you gradually in reproducing less colour and hence less battery sucking. Live Wallpapers and very colourful wallpapers must be avoided ..if battery is the concern.
-If you head into the device’s Settings and slide on over to System and then Battery, at the top you’ll notice two features. One is called Power saving mode. The other is called Ultra power saving mode as during some times when cell not needed in hand we can save some juice again.
- Google Play Services battery drain
Some users have reported that Google Play Services drains their Galaxy S6 battery quite a lot.
Go to Settings > Data Usage
Scroll down to see the list of apps
Press on Google Play Store
Switch Toggle to Restrict background data
Repeat step 3 and 4 for Google Play Services
Hard-restart your Galaxy S (not to be confused with hard-reset) by holding the volume-down and power buttons and release once the device turns itself off
Re-enable background data for Google Play Store and Google Play Services
-Fix Cell Standby drain by disabling VoLTE
-Disable Google Now and “OK Google” detection
If you’re not really using Google Now and voice commands, this quick fix will add a little – Disable location services:
We don’t necessarily need the location services unless we are using maps or any other app using the location. It’s easier to enable location when you are using any such apps. Consider turning it off otherwise to increase the battery life. Go to quick Settings and disable location services.
– Battery charge cycle:
It is recommended to let your device go through at least one charge cycle a month: i.e. charging the battery to 100% and then completely using it down. Power cycling this way helps in getting accurate battery usage data and is good for your battery maintenance too
-Fix Galaxy S6 battery by disabling notifications:
Receiving notifications for every single app is not only annoying but also eats up resources of both data, battery and the processing speed. Make efficient use of notifications and disable them for apps you don’t require notifications for.
--REGARDS