18650 battery powered Arduino DS18B20 temperature sensor would lost on average 2 years without to re-charge or replace the battery. It is best to use 3.3v Arduino Pro Mini with lower clock speed to conserve battery. To optimize battery life further you can remove power LED and status led connected to Arduino pin 13. Check out PiHome Shop for all you need for your Smart Heating 18650 battery powered temperature sensors are feed power to Arduino mini through raw pin…