I had this problem too. I prefer the Faenza-Dark variant but has a rubbish battery icon like in your screenshot. If you used the ppa to install the icons then you should have a Faenza-Ambiance/Radiance theme to choose which fixes it, but as I prefer the -Dark variant I had to make a custom version. What I did was copied Faenza-Dark to another folder like Faenza-Custom
sudo cp -r /usr/share/icons/Faenza-Dark /usr/share/icons/Faenza-Custom
Then edit it.
sudo nano /usr/share/icons/Faenza-Custom/index.theme delete everything in it and paste in this
Comment=Icon theme project with tilish style, by Tiheum
then use gnome-tweak-tool to choose the Faenza-Custom theme and it will have the fixed battery icon