This is the command for sending notifications from the battery monitor. notify-send "Battery low" --icon=battery-caution
lxpanel should depend on libnotify-bin and notification-daemon for executing this properly. So the temporary fix is, sudo apt-get install libnotify-bin notification-daemon add the following line to $HOME/.config/lxsession/LXDE/autostart @/usr/lib/notification-daemon/notification-daemon logout and get back in for the notification-daemon to start. The permanent fix should be to add the necessary dependencies and make the notification daemon start as a session service.
