I was using fluxbox on my notebook, but it missed battery indicator.Is there any battery monitor on fluxbox?
wmbattery then add it to startup script.
You might consider using conky which is a great lightweight system monitor that can not only monitor your battery state but many, many other functions of your computer.
In Manjaro Fluxbox there is a simple battery indicator applet called
mate-power-manager, which is more complete and looks better.
I dislike the look of slids and don't want to install something as heavy as
xfce4-power-manager so I am using xbattbar. It's in the repos and adds a green bar on the top/bottom according to your battery status.
xfce4-power-manager works fine for me