Is there anything you need to do / configure, as I am not getting that sort of battery out of my X1 Carbon running Mint. (I realize I usually leave bluetooth on, and the screen at mid to high brightness and have about 20-30 tabs open in firefox but I would still be lucky to get 5 hours out of it.)
On my machine mentioned upthread, I have a third party SSD installed which apparently fools the firmware into disabling SATA link power management. Powertop will tell you about most goofs like that.
Beyond that, run a current kernel (my measurements are on Fedora's 4.8.12 kernel). Also recognize that recent Intel SoCs have gotten a lot better at idle power draw. The "X1 Carbon" brand started with (I think) Ivy Bridge boards which obviously aren't going to perform like this.
Tiny almost weightless (feels lighter than current-gen Macbook Air) laptop, and it runs between 10 to 11 hours on the battery when doing normal work (programming, mail, web, spreadsheets etc..) on wifi with pleasant screen brightness ...
Linux power management is fine today on modern hardware... (Powertop reports 5.2-5.5 watts)