How can I check the battery level of a connected bluetooth device? The device shows the battery level on Android so I'm assuming the device supports the GATT-based Battery Service. However, by entering "menu gatt" in bluetoothctl and then listing the GATT attributes of the device with "list-attributes [dev]", nothing shows up.
A similar question was posted to SO but the OP seems to have found a solution that doesn't work for me. When I run "info [dev]" in bluetoothctl I don't see the UUID for Battery Service.
I would prefer a solution that runs on the command line and is distro-agnostic.
Please let me know if this question should be posted on SuperUser instead.
This might be a bit late to the party but for me this Python project has worked fine:
https://github.com/TheWeirdDev/Bluetooth_Headset_Battery_Level
I only had to change the port in line 57 to 3 for my no-name X5 headset. If it hangs or errors with "connection refused" try a different port.
The Python program uses AT commands via RFCOMM and should work while Pulseaudio is using the A2DP sink (mine reconnects). Python 3 is needed as 2 doesn't have BT-Serial sockets. Windows will probably not work as it lacks bluez. It basically does the same thing as the Pulseaudio hack here: https://stackoverflow.com/a/56390625/920122
If you want to look at the commands as they are exchanged, try my debug fork: https://github.com/clst/Bluetooth_Headset_Battery_Level