Install Xprivacy and block internet access to apps that dont need it.
You'll need this before you can install: Xposed Framework
Id recommend to turn off all battery saving apps that are turning off the wifi and or 3g/4g. You might think this helps but disable apps from doing this and do it manually yourself from the notification drawer.
-try a restart and see if Android Os goes down.
-after restarting, clear memory from the task manager.
-try disabling some apps notifications
-IM apps, I've had to disable/uninstall a few because they do cause battery drain.
- Your reception doesnt look good, apart from switching to flight mode (which is no solution), I dont know anything to reduce whatever effect that has on your battery.
Once you've got xprivacy go to the usage data(press the menu soft key whilst In xprivacy) and find what it is running in the background. This will help give you a better idea what is potentially draining your battery. Just be careful editing permissions on system apps as you could break them. Keep an action memo or screenshot of what you change if your a little unsure so you can revert back if something stops working.
Could you post screenshots of a full charge 100-1 % or nearabouts to that(normal use)
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