@Nanhaze: You can get an idea of potential sources of your battery drainage by heading to Settings > Device Care > Battery > Battery Usage, and checking the list of apps at the bottom of the page. I also recommend, with the above in mind, attempting the following steps in an effort to improve your overall battery life.
- Shut down all background apps when not in use via the Recent Apps button, especially those flagged towards the top of the list in Battery Usage.
- Turn off Wi-Fi, Mobile Data and Bluetooth when not in use
- Enable Power Saving Mode: Settings > Device Care > Battery > Power Mode > Select Medium or Maximum Power Saving.
- Reduce your screen brightness.