include battery status for beacon every x hours

I’m using also some BLE beacons with a CR2032 round cell, therefore it would be perfect to get some info of the battery status by a query which is made every x hours (e.g every four hours). If the BLE beacon is longer away than x hours, query it on first sight after x hours passed, otherwise wait until the timer is expired. Or if too complicated: just every x hours, as all beacons are usually at night in my home.