How to check battery status and information in Linux

Linux operating systems utilize the Advanced Configuration and Power Interface (ACPI) daemon to deliver essential battery information. This feature is available in most Linux distributions, ensuring users can easily access battery-related data. The battery information is stored within the /sys filesystem, a location that can be navigated from the command line, or you can use dedicated tools such as acpi and upower.

By accessing the /sys filesystem, or by using command-line tools such as upower or acpi, you can quickly and efficiently view your battery information in Linux.

1. Open a terminal application.
2. Explore the available battery information in the /sys filesystem.

   $ ls /sys/class/power_supply/BAT0/
   alarm           charge_full_design  device        present        technology          voltage_now
   capacity        charge_now          manufacturer  serial_number  type
   capacity_level  current_now         model_name    status         uevent
   charge_full     cycle_count         power         subsystem      voltage_min_design

3. Access specific battery data from relevant files.

   $ cat /sys/class/power_supply/BAT0/capacity
   100

4. Use the upower tool to view battery details.

   $ upower -i /org/freedesktop/UPower/devices/battery_BAT0
     native-path:          BAT0
     vendor:               Samsung SDI
     model:                DELL TXF9M6C
     serial:               34075
     power supply:         yes
     updated:              Fri 05 Jul 2019 11:27:48 AM +08 (91 seconds ago)
     has history:          yes
     has statistics:       yes
     battery
       present:             yes
       rechargeable:        yes
       state:               fully-charged
       warning-level:       none
       energy:              54.0968 Wh
       energy-empty:        0 Wh
       energy-full:         54.0968 Wh
       energy-full-design:  61.9932 Wh
       energy-rate:         0 W
       voltage:             8.504 V
       percentage:          100%
       capacity:            87.2625%
       technology:          lithium-polymer
       icon-name:          'battery-full-charged-symbolic'

5. Install the acpi userland application, if not already installed.

   $ sudo apt update && sudo apt install --assume-yes acpi #Ubuntu and Debian
6. Check battery charge status using acpi.

   $ acpi
   Battery 0: Full, 100%

7. Access detailed battery information with acpi.

   $ acpi --battery --details
   Battery 0: Full, 100%
   Battery 0: design capacity 8157 mAh, last full capacity 7118 mAh = 87%