Short Answer. 36+ Months.
Applies to Conserv Smart Collections Sensor, Conserv Cloud
Monitoring battery life
Conserv is monitoring for sensors that may have a premature battery drainage. We'll get an alert if we see an issue with your battery and will reach out to get the best mailing address right away. Our goal is to make battery life something you don't have to think about.
For customers with an active monitoring subscription, we will replace your sensors every 36 months. Because the sensor battery life is 36+ months, our expectation is that you will never have to change your sensor batteries. Easy, right? 😀
If your sensor batteries die before your expected replacement, that means something unexpected is going on. Please reach out to us through our help form so that we can identify that problem and get your sensor up and running again.
Some of our customers prefer to have extra batteries on hand. If you wish to purchase them, you can find them here. These are the batteries we use:
AA Lithium Thionyl Chloride 3.6 V Battery Non-Rechargeable - Tadiran
Battery life design
We've designed our sensors to run for 36 months sending temperature, relative humidity, light, and movement data wirelessly every 15 minutes. The actual expected battery life is 48 months, and we've added 12 months as a buffer. However, there are certain things that can interfere with the full projected lifetime of a battery (such as: temperature, extensive readings from moving the sensor a lot, a prolonged period of time where the sensor attempted to connect with the gateway initially).
Our sensor contains two 3.6v lithium (LiSOC2, specifically) AA batteries, providing about 4800mAh of total battery capacity. Our sensor sips power, consuming less than 50uAh when it is asleep. That sleep period accounts for 99.9% of a sensor's life. Sleep, wake up, take some readings, send some messages, and then back to sleep.
The expensive part of a power budget for wireless monitoring is sending the data over the air. This is why sensors based on technologies like WiFi have to make compromises that might include shorter reading intervals, less frequent data transmission, extra batteries (some use 4x AA!) or shorter battery life. A wireless LoRaWAN radio transmission only lasts a few hundred milliseconds (at worst), and only consumes a few mA while the transmission is sending. For Conserv this means we expect to be able to send well over 150000 readings on a single set of batteries. Sending one message every 15 minutes, that's approximately 1500 days of battery life. We say "approximately" because there is always some variability in battery capacity, and things like vibration / motion triggers can move that number around a bit.
We chose this design because our customers have told us that dealing with dead batteries is a pain. The combination of high capacity batteries and extremely low current consumption means battery life is something you shouldn't need to worry about.
LiSOC2 Lithium, AA size
|Battery capacity||2x 2400mAh, total 4800mAh|
|Average sleep power consumption||50uA|
|Configuration mode power consumption||8mA|
|Average transmission power consumption||2.5mA|