Battery Bar Graph UWP overwhelming and (currently) free
(All About Windows Phone)

With only minimal set-up, this new UWP utility shows a wealth of power and battery data on live tile, on lockscreen and on Glance screen (if your device has this). Impressive. The only caveat is that the data shown is overwhelming in terms of stats and with no way (currently) to customise its output. Ah well. Still worth a look, if only because it`s cool!