What is the life span and replacement procedure for CellCom/FreeSpeak basestation and Pico batteries

The 3V battery is lithium ion so its not charged when the unit is powered
Both use 970mAH batteryMk1 standby current = 10uA so 97000 hours = 11 years ...this is the older unit, with the large daughterboard on the left side of the main PCBMk2 standby current = 15uA so 65000 hours = 7.4 years...this is the newer unit with just one main board.
The NVram stores -the map -which memory bank to run the main application from.-the IP address  So if changing the battery make sure to back up your map and note the IP address and passcode, if applicable of the basestation  pull out the AC mains cable and change the battery. Send you map back in via serial connection re-enter the passcode
Note: the main app and the V2.0 passcode are stored in flash.

Pico CPU card will retain data so long as the battery voltage remains above 1.5V.  2.5V


Solution update: Pico CPU low battery voltage changed to 2.5V on Feb 2021