A GNOME shell extension to show the remaining time until fully charged/discharged as well as battery charge in percent in the panel.
This is a fork of the excellent https://github.com/mzur/gnome-shell-batime.
If you want just the battery percentage, gnome shell already can do that by itself. Run this on a terminal:
gsettings set org.gnome.desktop.interface show-battery-percentage true
If you want just the battery time, use the original extension, Battery Time