i wrote a simple plugin to display the percentage of battery on fbpanel (i am using openbox + debian)

put this code inside ~/.config/fbpanel/default

Plugin {
type=genmon
config {
Command = echo $(acpi -b | cut -d, -f2)
PollingTime = 2
TextSize = small
TextColor = red
}
}

this is how it look like
fbpanel battery status