Powercfg Ich kann nicht sprechen Deutsch
It is however more severe, that powercfg doesn't speak correct XML.
If you look at the various screenshots of powercfg in this thread from posters with German language setup, you will see, that all the powercfg reports are in English anyway, even on Windows system setup for German (Besides the English language, you will also see English date formatting). Error messages on the command line are in German and obviously parts of some intermediate files also. So it looks really like a mess, that has never been tested well in the German language setup.
Haldi, I hope you can find the rigth place to adress this bug. Maybe a coder can fix the unmatched quotes in 15 minutes. Overall effort will still add to much more (understanding the problem, finding the right setup to reproduce it, finding the right persons to fix it, setting up the correct testing, QA, packaging things for patches, writing release notes, ...). Of course, it should be done!
Fixing the confusion with the decimal seperator (In a German setup, powercfg shows in its reports 42 mWh of battery capacity instead of 42000 mWh) might need even more time. I believe, this is the reason, that there are many empty cells in the report, where one would expect capacity values. It might be the reason, for sometimes strange battery-runtime estimations.