why does my iMac not warn me when battery is getting low on keyboard or mouse?

If you visit the Bluetooth preferences and choose to show that symbol in your iMac's menu extra area, then by clicking on that, you can see the current battery level of Bluetooth-attached Apple devices.

I have never been alerted to low battery for these Bluetooth devices because I usually charge them when they drop under 40%.

I just ran the following on my M1 mini (macOS 11.7) with the two Bluetooth devices still attached as in my previous post above.

ioreg -r -l -k "BatteryPercent" | egrep -io '("LowBatteryNotificationPercentage"|"BatteryPercent") = \d+'



Got these results, so now we know how low the low battery notification has to sink:

kitcarson wrote:

warn me when mouse &keyboard are needing a charge

Mine does warn me (wireless keyboard and mouse sets, used on two MacBook Pros and two iMacs) but it warns when the charge level is VERY LOW, very little advance warning before they shut down. Using 12.6.

dialabrain wrote:

How low is "VERY LOW"? Apparently I've never let mine get that low.

Something below 5%, maybe even 3%. It is not enough time to do much of anything except connect a cable to charge it. With a laptop, one can simply use the trackpad or built in keyboard while those items are charging, but on an iMac one is out of luck unless one has a cabled mouse to use temporarily (the keyboard can be used while charging).

I'm not positive but I think the lowest any of mine were before I charged them was 53%

You would have to ask Apple and they aren't here.

How low is "VERY LOW"? Apparently I've never let mine get that low.

That is low. Even my remotes for the TV and DVR warn me long before that. Probably why I've never seen it.

Interesting. When I run that command I get nada. No results, no error.