EnGenius UHF-BA Cordless Phone Compatible Battery 3.7V 1800mAh

EnGenius UHF Series — 3.7V Li-ion Replacement Battery (UHF-BA)

This is a 3.7V, 1800mAh Li-ion battery for the EnGenius UHF cordless handset. It replaces OEM part UHF-BA and restores power to UHF-series handsets used in business and field communications. Dimensions are 53.00 × 35.30 × 11.00mm — confirm fit before installing.

• UHF handset compatibility: The UHF-BA form factor is specific to EnGenius UHF-series handsets. The cell voltage, connector pinout, and BMS charge profile all match what the base station expects. Swapping a different cell type will cause charge rejection or inaccurate capacity reporting on the handset display.
• Bench tested on actual hardware: We cycled this battery through charge and discharge on UHF-compatible test rigs. The BMS held cutoff correctly at low-voltage threshold and accepted a full charge from a standard EnGenius base without triggering a fault light.
• First charge on the EnGenius base: After installing this battery, seat the handset in the base for a full uninterrupted charge before first use. Li-ion cells shipped in storage state need a complete charge cycle to let the BMS calibrate the capacity register — cutting the first charge short will cause the handset to show a lower battery reading than the cell actually holds.

Talk time shorter than rated after fitting the new battery

A new Li-ion cell ships at partial charge, and the BMS starts with no usage history to calibrate against. The handset's fuel gauge reads the cell state inaccurately until it has seen at least one full charge-to-discharge cycle. Run two or three complete cycles — full charge on the base, then use until the handset signals low battery — before judging talk time. After cycle three, the BMS calibration settles and the displayed battery level becomes accurate.

EnGenius base station showing no-charge or error light after battery swap

EnGenius bases check for a minimum handset voltage before starting a charge current. A battery that has sat in storage can drop below 3.0V, which the base reads as a fault condition rather than a depleted cell. Remove the handset, wait 30 seconds, and reseat it firmly — some bases retry the voltage check on reconnect. If the error persists, check that the handset contacts are clean and that the battery connector is fully seated; a partial connection drops apparent voltage further and keeps the base in fault state.