Netgear Around Town 4G LTE Compatible Battery 3.7V 2400mAh

Netgear Around Town 4G LTE (AC778AT-100NAS) — 3.7V Li-ion Replacement Battery

This 3.7V, 2400mAh Li-ion battery replaces the original cell in the Netgear Around Town 4G LTE mobile hotspot (AC778AT-100NAS). It fits the battery bay directly and connects to the same BMS interface the hotspot firmware expects. If your original battery no longer holds a charge or the device shuts down unexpectedly under load, this is the swap.

• AC778AT-100NAS compatibility: The Around Town 4G LTE pulls power from both its cellular modem and its WiFi radio simultaneously. The battery must meet the BMS handshake the hotspot firmware expects — wrong cells trigger a charge refusal. This cell matches the voltage rail and communication protocol.
• Bench tested on actual hardware: We ran this battery through charge cycles on the AC778AT-100NAS and monitored BMS response under combined modem and WiFi load. The protection circuit handled current spikes without tripping the cell into cutoff.
• Ventilation during extended sessions: Keep the hotspot flat on a hard surface with airflow underneath during long sessions. When connected devices are far away, the cellular radio runs at maximum output, generating sustained heat that accelerates cell wear. Avoid pockets or enclosed bags while the device is active.

Hotspot disconnecting users mid-session on a new battery

A freshly installed battery can still cause mid-session dropouts if the hotspot is connected to its maximum number of devices simultaneously. The combined draw from the cellular modem and multi-device WiFi load pulls the cell voltage below the BMS protection threshold briefly — the firmware reads this as a fault and resets the radio stack. Reducing active connections from the admin panel at 192.168.1.1 lowers the instantaneous current draw and keeps the cell above the cutoff floor. If dropouts persist, check that the cell is seated flush and the contact pins are clean.

Hotspot shows charging but voltage stays flat

If the battery indicator moves slowly or stalls during charge, the original USB cable or charger is usually the cause — the AC778AT-100NAS requires a stable 5V input and a weak supply causes the BMS to throttle charge current. Try a known-good charger rated at 1A or higher. If voltage stays below 3.5V after 30 minutes on a good charger, the contact pins inside the battery bay may need cleaning with a dry cloth. A full charge cycle from flat should bring the cell to 4.2V at the pack terminals.