How can I see the battery status of my Logitech wireless mouse?

Solution 1:

From the CLI, UPower can do this:

$ upower --dump
Device: /org/freedesktop/UPower/devices/mouse_0000o0000o0000x0000
  native-path:          /sys/devices/pci0000:00/0000:00:14.0/usb3/3-9/3-9.4/3-9.4:1.2/0000:0000:0000.0000/0000:0000:0000.0000
  vendor:               Logitech, Inc.
  model:                Anywhere MX
  serial:               00000000
  power supply:         no
  updated:              Sun 10 Jul 2016 04:47:36 AM EDT (84 seconds ago)
  has history:          yes
  has statistics:       no
  mouse
    present:             yes
    rechargeable:        yes
    state:               discharging
    warning-level:       none
    percentage:          95%
    icon-name:          'battery-full-symbolic'
[...]

From the GUI, mate-power-statistics (from the MATE Power Manager project) or gnome-power-statistics (from the GNOME Power Manager project) can do this.

Solution 2:

Using the Solaar program as described in this answer, you can obtain the battery status.

warning: technical gibberish below, feel free to skip if you are not interested in hacking this mouse

The M510 is a HID++ 1.0 device judging from the register dump at the Solaar repository. The HID++ 2.0 document that include Battery Unified Level Status as linked by gertvdijk are irrelevant here.

As noted on https://git.lekensteyn.nl/ltunify/tree/registers.txt, the "07" register shows the battery status. If you want to learn more about the technical side, you can read my article about reverse engineering the protocol.

Solution 3:

You can go to your power settings. There you will hopefully have the battery left of any device that runs on batteries.

In my distro (Mint) I can see the battery remaining of my laptop and my mouse by clicking in the power icon at the status bar (bottom-right).

I can also go to power management, and there is a "Batteries" tab, and there it is too.

I don't know if this is available in all distros, but it is so easy to check that there's no harm in giving it a try.