Automatic Notification for the Laptop Battery Level

While working from home one of the issue I faced that my laptop battery charger adapter is always remain plugged in almost all the time, due to which I have to replace my laptop battery. To deal with the problem I have now written a script to notify me about the laptop battery charging level if it goes above 85 % and below 20%.

#! /bin/bash                                                                                                                                          

while true
do

    battery_level=`acpi -b | grep -o '[0-9]*' | sed -n  2p`
    ac_power=`cat /sys/class/power_supply/AC/online`

    #If above command raise an error " No such file or directory" try the below command.
    #ac_power=`cat /sys/class/power_supply/ACAD/online`
    if [ $ac_power -gt 0 ]; then
        if [ $battery_level -ge 85 ]; then
            notify-send "Battery Full" "Level: ${battery_level}%"
        fi
    else
        if [ $battery_level -le 20 ]; then
            notify-send --urgency=CRITICAL "Battery Low" "Level: ${battery_level}%"
        fi
    fi
    sleep 120

done

The important commands which I want to break down to explain actually what they are doing.

>> acpi -b
Battery 0: Discharging, 54%, 02:03:37 remaining
>>acpi -b | grep -o '[0-9]*'
0
54
02
04
41
>>acpi -b | grep -o '[0-9]*' | sed -n  2p
54

To make this script run automatically you have to assign the execution permission and specifies the execution command in the ~/.profile and reboot the system.

>> sudo chmod +x /path/to/battery-notification.sh

you can find my notes on shell commands here

thanks shrini for pointing out issue for Ubuntu 20 in lineac_power=`cat /sys/class/power_supply/AC/online` :) Cheers!

#100DaysToOffload #automation #scripts