Keyboard low battery warning

I've been using wireless keyboards on my Mac computers for years. While the reminders that the keyboard batteries are low are a little annoying, having the keyboard die unexpectedly is more annoying. Batteries can't be replaced like in the older keyboards, so the only option is to plug in to charge (which is not always possible if using the laptop for teams meeting etc). I've hunted through the keyboard and Bluetooth settings, but can't find any way to switch on 'notify me when the keyboard batteries are getting low'.

Can anybody help, please?

*2020 M1 Macbook Pro, Ventura 13.2.1, Magic keyboard (touch ID, rechargeable via cable only).