Netgear AirCard 790 Replacement Battery W-7 3.7V 2400mAh

Netgear AirCard 790 / 790s Series — 3.7V Li-ion Replacement Battery (W-7)

This is a 3.7V, 2400mAh Li-ion battery for the Netgear AirCard 790, 790s, AC790S, and AirCard 779S 4G mobile hotspot range. It slots into the same bay as the original W-7 cell and restores wireless operation away from mains power. Use the capacity figure above — 2400mAh — as the reference spec.

• AirCard 790 series compatibility: The 790, 790s, AC790S, and 779S 4G all share the same W-7 battery footprint, connector pin-out, and BMS handshake protocol. Swapping between variants in this family does not require a different cell.
• Bench tested on actual hardware: We cycled this battery under a combined cellular modem plus multi-device Wi-Fi load. The BMS held voltage above the cutoff threshold at full connection count and flagged charge state accurately throughout each cycle.
• Ventilation during sessions: Keep the hotspot on a hard, open surface during extended use. When connected devices are far from the unit, the cellular radio runs at maximum transmit power — the resulting heat builds inside any enclosed space and stresses the cell faster than normal ambient conditions would.

Hotspot warm and throttling during long sessions on a new battery

The AirCard 790 runs two power-hungry radios simultaneously — the cellular modem and the Wi-Fi access point. Under sustained load with multiple clients connected, both radios draw peak current at the same time. The BMS interprets elevated cell temperature as an overload condition and steps down output to protect the cell. If the unit feels hot and connection speeds drop, move it to open air and reduce the number of active client devices until temperature normalises.

Hotspot not powering on after sitting unused for several weeks

Li-ion cells self-discharge at roughly 2–3% per month at room temperature. If the AirCard 790 was stored without a charge top-up, the cell can drop below the minimum boot voltage — typically around 3.0V — and the BMS will block startup to prevent damage. Connect the unit to the original Netgear charger and leave it for at least 30 minutes before attempting to power on. If the charge LED does not respond at all, the cell may need a slow pre-charge recovery cycle, which most OEM chargers initiate automatically from a trickle state.