Six months at least on about 50 mah battery without going below 12v. Boron LTE wake every 15 minutes to publish heartbeat and alert if certain conditions are met.
At this point I’m trying to get a lot more energy efficient. I’m draining a 1.2 ah test battery in about 12 hours (solar panel brings it back up during the day) publishing every 15 minutes and sleeping in between: On wakeup turn cell chip on, connect to cloud(s), publish, disconnect from cloud, turn cell chip off, then System.sleep(sleepWakePin, CHANGE, 900).
Things I still need to try:
Reduce publishes to absolute minimum #
Try sleep_mode_deep (lose ability to store variables for unknown gains)
Instrument actual consumption and check against specs / community observations (any help here would be nice in terms of simplest way to sample consumption over time)
Try keeping cellular connection up instead of connecting and disconnecting (system mode semi-automatic (cell connection but no cloud) and sleep with SLEEP_NETWORK_STANDBY). Unlikely to show gains with LTE, but what the heck.
Edit: Changed 1.2 ah battery drain in 24 hours to 12. Solar panel brings it back up, and it drains over night (under 12v).