Cmos battery status on X86 generic machines

[rosariopomillo]

Describe the feature

I'd like the ability to monitor cmos battery status on my 3 homeassistant systems.

Use cases

2 of my homessistant istallations are far away (150 and 1300 km). They and are really reliable systems. The only weak point is the cmos battery. In remote locations if mains fails for long times (30min or more), AND the cmos battery is low, bios restarts at legacy values, UEFI is not available, and homeassistant fails to boot.

Current workarounds

UPS solves only short time mains failure.

Anything else?

This is to replace cmos battery before it is totally dead.