Modem Backup Batteries for Arris and Technicolor Gateways

A backup battery slides into the battery bay of a telephony modem or gateway and keeps it powered when the electricity goes out. This collection includes replacement backup batteries for Arris and Technicolor gateways, including the Arris BPB-series packs used across the TM and TG telephony lines, each matched to specific gateway models.

If your home phone service runs through your modem, this small pack is what keeps that line available in a blackout. And if it has been a few years since your gateway was installed, odds are the original battery no longer holds a charge, or your provider never included one at all, since many providers now direct voice customers to supply their own.

Why Add a Backup Battery to Your Internet Setup

• Phone service stays up: Provider voice service is delivered through your gateway, so when the gateway loses power, the phone line goes dead. A charged backup battery keeps calls working during an outage, including 911, as long as your provider's network is up.
• Rides through power flickers: A momentary blip forces a modem to reboot and re-sync with the network, which can take several minutes. A battery carries the gateway straight through, so your connection never drops.
• Internet during short outages: A battery-backed gateway with built-in WiFi keeps laptops and phones online while the power is out, handy for finishing a work call or checking an outage map.
• Protects connected systems: Especially important if a medical alert system or alarm panel depends on your phone line staying live.

One tip that trips people up: cordless phone base stations need wall power, so keep one corded phone in the house if outage calling matters to you.

Match the Battery to Your Gateway

Backup batteries are model-specific. The fastest way to identify yours is to open the battery door on your gateway and read the part number printed on the existing pack, then match it to the compatibility list on the product page. If the bay is empty, search by your gateway's model number instead. Installation takes seconds: the pack clicks into the battery bay with no tools.

Why Buy Modem Batteries from ModemGuides

Every battery we sell is tested before it ships and covered by our 90-day full-coverage warranty, and our US-based support team can confirm compatibility with your exact gateway model by chat or email before you order. If you are replacing the whole unit instead, our modem router combos and cable modems include telephony models with battery bays, including Xfinity-compatible gateways for Xfinity Voice service.

Frequently Asked Questions

Do I need a backup battery for my modem?

If your home phone service comes through your gateway, yes: without a battery, the phone line dies the moment the power does. If you only use the gateway for internet, a battery is a convenience rather than a necessity, though it still smooths over flickers and short outages.

How long does a modem backup battery last during an outage?

Runtime depends on the gateway and the battery's capacity, but most packs provide several hours of standby time, enough to cover a typical outage. Active talk time draws the battery down faster than standby.

How often should backup batteries be replaced?

Like any rechargeable pack, gateway batteries lose capacity over time and typically need replacement after a few years. Most telephony gateways flash a battery status light when the pack no longer holds a charge.

Will a backup battery keep my WiFi on during an outage?

Only if the WiFi comes from the battery-backed gateway itself. A separate router plugged into the wall goes down with the power, so pair it with a small UPS if whole-network uptime matters to you.

Which battery fits my Arris or Technicolor modem?

Check the part number printed on your current battery, or your gateway's model number, against the compatibility list on each product page.

Not sure which pack your setup needs? Our US-based support team can help before you order.