I can help you with a tips about charging your battery. Never charge your mobile devices battery unless it is under 10%. Then fully charge it without any interruption. I am following this rule and I am benefited with this rule. Not only me, I told it to my friend who was suffering from a battery issue. But not he is satisfied with his battery life.

Oh boy! I needed this! My S6 runs out of battery so quick! (I think I might go back to those old Nokias LOL)

Enabling Battery Saving Mode:

1. From the home screen, tap "Apps" and go to "Settings"
2. Swipe to "System"
3. Tap "Battery"
4. Tap "Power saving mode" to enable the feature

Ultra Power Saving Mode:

1. Access the "Settings" menu
2. Swipe to "System"
3. Tap "Battery" > "Ultra Power saving mode"
4. Tap the "Ultra Power saving mode" switch and set it to "ON"
5. You can customize how Ultra Power saving mode works for various apps including "Phone", "Messages" and "Internet"
6. To add more options, tap "+"

Lower the Screen Brightness and Adjust the Timeout Duration:

1. Access the phone's "Settings" menu
2. Swipe to "Device"
3. Tap "Display"
4. Tap "Screen timeout" and adjust a lower value
5. From the "Display" menu, tap "Automatic brightness" to adjust / lower the settings

Disable Wi-Fi, Bluetooth, GPS and Hotspot:

NOTE: you can gain more battery life by disabling the phone's connectivity features when they are not in use. To do so:

1. Tap "Apps" from the home screen
2. Go to "Settings"
3. Swipe to "Connections"
4. Tap the connectivity option(s) you wish to disable

Change Sync Settings for Apps:

1. Go to the "Settings" menu
2. Swipe to "Personal"
3. Tap "Accounts"
4. Select the desired account
5. To change the sync settings for certain apps only:
   
   1. Select the desired account
   2. Clear the boxes associated with the apps / services you don't want to sync
   3. When ready, tap the "menu" icon > "Sync now"

Disable Background Data:

1. Open the "Settings" menu
2. Scroll to "Connections"
3. Tap "Data usage" > "More"
4. Tap "Restrict background data" and press "OK"

Minimize the Use of 3rd Party Apps:

NOTE: Some apps can affect your phone's battery performance even when they are not in use. If certain apps run processes in the background that affect the battery performance on the long run too much, you can disable or remove them:

1. Tap "Apps" > "Settings"
2. Scroll to "Device"
3. Tap "Applications" > "Application manager"
4. Swipe to the "Downloaded" menu
5. Select the desired application
6. Tap "Disable" / "Stop", or "Uninstall" to completely remove the app

Switch from 4G to 2G Connectivity:

1. From the phone's "Settings" menu, scroll to "Connections"
2. Tap "More connection settings"
3. Tap "Mobile networks" > "Network mode"
4. Select one of the following "LTE / WCDMA / GSM (auto connect) (LTE setting)", "GSM / WCDMA (auto connect)", "WCDMA only" or "GSM only (2G only setting)"

Check for Software Updates:

NOTE: Software updates sometime include fixes or improvements to battery life, so it's recommended to keep your phone up to date with the latest available software. To check for updates:

1. Tap "Apps" on the home screen
2. Access "Settings"
3. Scroll to "System"
4. Tap "About device"
5. If a software update is available follow the on-screen instructions to download and apply it on your phone