Rule behavior changed after going from 2.3.0.124 to 2.3.1.137

You might also try Device Activity Check which can simply let you know when a device battery dies and it goes offline. I use this for all my battery devices. I gave up on battery level notifications, because many of my devices hang at 1% or 0% for WEEKS before they completely die, and as a result I was changing batteries much more often than I needed to change them.