Why are `battery` sensors forbidden from display on the default dashboard?

Lovelace appears to filter out any sensor of device_class: battery when presenting a default dashboard.

Default dashboards will display any custom groups, including all of their defined entities, even if they have an entity status of “hidden”—except for sensors of device_class: battery, which won’t be displayed even if they have an entity status of “enabled”.

If I then take control of such a default dashboard, sure enough, any battery sensor is missing.

Is this intentional? I can’t find anything in the docs to explain this behaviour, and I can’t think of any obvious benefit for these to be explicitly excluded.

Preempting some anticipated questions:

  • Yes, I know that other sensors are also excluded from default dashboards, such as those shown under the Diagnostic header of the device page. However, if I add such sensors to a group, they are usually then displayed on a default dashboard—unless they’re a battery sensor.
  • Yes, I know that I can get them displaying on controlled dashboards. I’m keen to get them displaying on my default dashboard though, which I (try to) use as a catch-all/debugging view for most available sensors without having to modify it every time a sensor is added or removed.

You’re right - I’d never noticed. Binary sensors relating to batteries seem to be there, but not battery level sensors - these do come under diagnostic on the device page, however.