I have been testing Zwave/Zigbee Temp Sensors over the last few weeks.
I'll put out my findings on all the rest but so far as a Battery temp Sensor the HUE MOTION SENSOR is by far away the BEST Temperature Sensor.
It is the best because it is incredibly reliable at sending sensor reporting and uses 2 AAA batteries which last 2 years. They are just SOLID.
I had assumed this reliability was ALL in the HUE Motion Sensor so did some testing on Hue Temp Sensors under Hue and Hue Temp Sensors under HE.
My findings were quite illuminating.
I have about 30 Hue Motion Sensors in the house evenly spread across two Hue v2 Hubs and 1 HE C7.
I have been graphing 5 Hue Motion Sensors running under HE and 4 from the two Hue Hubs.
Hue Motion Sensors under Hue Hubs report back to HE C7 (using cocohue App) 8 times per hour
The Hue Motion Sensors under HE C7 report a temperature on average 1 per hour, and that number is misleading, one sensor reported back 19 times in the 5 hour test, the rest once.
The HE settings for the Hue Motion Sensor are all Report on 0.5c change and all locations where the sensors are experienced Multi degree changes during the 5 hour period.
************* It may be that the zigbee mesh may not be that great - but all of these sensors are within 20 ft of the HE Hub. So to be sure I have ordered 4 Ikea Zigbee Repeaters and they will arrive next week and I will test again.
But at the moment the most reliable of the zwave/zigbee BATTERY Temp Sensors is the Hue Motion Sensor running under HUE connected to HE C7 with cocohue App.