Southwestern Bell F-940 Cordless Phone Replacement Battery 3.6V 700mAh

Southwestern Bell F-940 / FF-9915 / GH-2400 Series — 3.6V Ni-MH Replacement Battery

This is a 3.6V, 700mAh Ni-MH replacement battery for Southwestern Bell cordless phones including the F-940, FF-9915, GH-2400, and GH-2410, plus 23 additional handset models. It slots directly into the handset battery compartment and restores wireless calling range and talk time. Dimensions are 45.60 × 31.30 × 10.60mm — confirm these against your original pack before ordering.

• F-940 and GH-series compatibility: These handsets share the same 3.6V single-cell Ni-MH format, physical footprint, and connector orientation. One battery pack covers all models in this cluster without modification.
• Bench tested on actual hardware: We cycled this pack through charge and discharge on a cordless phone test rig. The cell voltage held above the 3.2V handset low-battery threshold through full talk sessions, and the base station accepted the charge contact without error.
• First-charge conditioning for Ni-MH handsets: After installing the new pack, place the handset in the base for a full 16 hours before first use. Ni-MH cells ship partially discharged and require this slow initial charge to reach rated 700mAh capacity — skipping it leaves the cell permanently under-conditioned.

Range dropping on the F-940 after a battery swap

The F-940 DECT transmitter draws a sharp current spike during each RF burst. If the Ni-MH pack hasn't completed its first conditioning cycle, internal resistance is higher than rated, and cell voltage sags under that RF load. The handset interprets the voltage sag as a weak signal and reduces transmit power. After three to five full charge-discharge cycles, internal resistance falls and the voltage stays stable — range returns to normal without any settings change.

Base station shows no charge or error light after fitting the new pack

Ni-MH batteries self-discharge during storage and can arrive below the minimum voltage the base station expects before it begins a charge cycle. If the base shows no charge activity or an error indicator, the pack may be too low to trigger the charger's acceptance threshold. Remove the handset, wait 30 seconds, and re-seat it firmly so both charge contacts close cleanly. If the light still doesn't activate, check the contact pins on the handset for debris — a brief wipe with a dry cloth and re-seating resolves most cases.