Arduino backup power supply - Electrical Engineering Stack Exchange
Dc 12V 24V 36V 48V 10A Power Supply Battery Controller Emergency Automatic Switch Module Emergency Dc Backup Battery Ing Module: Amazon.com: Industrial & Scientific
Datalogging with power-loss protection & How to make a battery backup circuit if mains fails (using mosfet) - #17 by GigaNerdTheReckoning - General Electronics - Arduino Forum