How long can be available for N5810PRO internal li battery (BBM)

The N5810PRO internal li battery (BBM) doesn’t like laptop or external PSU, this function prevent from NAS AC power lose only. Since system found AC power lose, and would going to re-check AC power resume or not, if over 2 mins AC without resume, and NAS will going to normal power off process prevent from power lose leading RAID degrade or damaged.