I have a lot of #Mote2 sensors I use. Most are powered by a 3V coin cell (CR2032) and are able to survive for a long time (usually around 10 months) transmitting temperature/humidity data every 5 minutes.

But one in my shed really amazed me. I remember that I replaced it’s battery over a year ago, and it still kept on going. How, why? I can’t explain. It should’ve have lasted 456 days, and yet it did somehow…  Simply amazing…