=====upower=====    
  * <code>upower -e</code>
  * <code>upower -i /org/freedesktop/UPower/devices/battery_BAT0| grep -E "state|to\ full|percentage"</code>
  * <code>upower -i /org/freedesktop/UPower/devices/battery_BAT1| grep -E "percentage"|sed 's/    percentage:          \(..\)%/\1/g'</code>