They gave me a battery with my equipment and now I have to replace with my own money because NOW then told me it is optional. Can't wait to return to Comcast when I contract expires!!!!!!!!!!!!!!!!!!
I'm guessing you 're talking about the ONT battery for FiOS. I hope you're not talking about a remote control battery.
The ONT's battery is used to keep voice service up during a power outage.
If you don't care about voice during an outage, or if you don't have voice, you don't need the battery.
Even when Verizon provided the battery for free with install, they never provided free replacements.
Comcast charges for batteries, too.
You can find FiOS ONT batteries online for much less than Verizon's price.