That’s quite surprising, I’ve been really impressed at the battery life. Have a look in Settings -> Power Management -> App power consumption to see what’s using it up.
If you’ve got lots of power being used by (I think) “Media Server” it could be a problem with the SD card. Mine would initially hammer through the battery because I had corrupted files on the SD card it kept trying to read. Popping it into a PC and running Checkdisk on it fixed the issue.
GSAM battery monitor on the play store also good to get a detailed breakdown of what’s using the battery.