Incorrect battery level after resume

[Damian Friedli]

After upgrading from the latest 14.04 LTS to the latest 16.04.2 LTS on my Lenovo Thinkpad X1 Carbon, the battery level is detected and displayed incorrect after charging the battery while the system is suspended.
Example: I work in my notebook while it is not connected to the power supply until the battery is down to lets say 4%. I'll close the lid (=> suspend), bring it to the place where I have the power supply and connect for charge. After my break, I'll disconnect the still suspended notebook, take it back to the place I used to work in it(for example outside; there is no power on that place, can be far from the place where I charge it) and open the lid to resume the system. Every time I'll get shocked and doubt if the battery was charged properly because it will still show the level from before, e.g. the 4%. In some cases when the battery level is detected as critically low, the system will directly suspend again, thinking the battery is going to get empty. If I want the battery level to be displayed correctly, I have to connect the charger while the system is not suspended which can be a pain in the a** when I am far away from the power supply.

Eventually I now found another workaround for this problem with creating a script in /usr/lib/pm-utils/sleep.d with somethink like

...
thaw|resume)
 service upower restart
 ;;
...

Anyway, I think something basic like detecting the correct battery level on a notebook on an Ubuntu LTS release should really work out of the box without that kind of workaround.

$ lsb_release -rd
Description: Ubuntu 16.04.2 LTS
Release: 16.04

$ uname -a
Linux c4rkb0n 4.8.0-46-generic #49~16.04.1-Ubuntu SMP Fri Mar 31 14:51:03 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux