My understanding is the battery backup is more for the phone (landline) for emergencies if the power goes out (and not so much for the tv/internet). However , our battery went bad a few weeks ago and it took out ALL our verizon services (tv/internet/phone) when it went . We had to call and have it replaced . Seems to be a semi-common issue after having FIOS for quite a few (4-6-8) years .
I must say Verizon did a nice job on our replacement as they took care of our outage (battery replacement) with-in a few hours of our service request .
