NBN Battery Replacement for NBN™ for Sale NBN battery replacement for NBN™ Power Supply Units. If you chose to have a Power Supply Unit with Battery Backup included with your NBN™ installation, you will have an existing sealed lead acid Lc12v-7.2amh battery. The NBN battery replacement is cost-effective, for sale at a great price whilst providing a high quality, NBN approved product thus assuring a long service life of the replacement battery. When your NBN battery has lost its charge, your Power Supply Unit will show a red light next to the ‘REPLACE BATTERY’ symbol or you will hear an alarm beeping once every 15 minutes, indicating you need to replace your battery with a new one. With our NBN battery replacement service with 12 months warranty and shipping Australia wide you can feel secure in your replacement