We were recently asked the following question:
Your datasheet states that the battery life of the zymbit 4i is approx. 2.5years. Is this figure increased if the device is powered?
It’s an excellent question!
From our product data sheet:
ZYMKEY 4i includes a battery-backed real time clock to support off grid applications:
• 18-36 month operation, application dependent
• RTC clock service, available to client applications
• RTC/UTC anamoly [sic] alerts available with zymbit security services
• 20ppm accuracy (standard). Optional 5ppm accuracy (OEM feature, MOQ apply)
The battery life quoted is based on the life of the battery in an unpowered state (the Zymkey is not powered on via the Pi).
That being said, when the Pi is powered, the battery life can be extended nominally to ~10 years. As with all batteries the ultimate useful lifespan is limited but the quality of the battery and the internal leakage over time.
Hope this is helpful!
dg