Uniden EXP901 Replacement Battery 3.6V 1500mAh Ni-MH

Uniden EXP901 — 3.6V Ni-MH Replacement Battery (BBTY0241001)

This is a 3.6V, 1500mAh Ni-MH battery for the Uniden EXP901 cordless phone handset. It replaces OEM part numbers BBTY0241001 and BT-901. If your handset no longer holds a charge or dies early in a call, this battery restores normal handset operation.

• EXP901 handset fit: The EXP901 uses a 3.6V three-cell Ni-MH pack with a specific contact layout matched to the handset cradle. This battery matches that voltage, capacity, and connector orientation so the handset seats and charges correctly in the base station.
• Bench tested on actual hardware: We cycled this pack through the EXP901 base station's charge circuit. The BMS accepted the charge without flagging an error light, and voltage held steady across the talk and standby draw profiles of the handset.
• First-charge protocol for Ni-MH handsets: After installing this battery, place the handset in the base and leave it for a full 16 hours before first use. Ni-MH cordless phone cells arrive partially discharged from storage. A slow first charge lets the cells reach rated capacity and sets the baseline for the base station's charge termination circuit.

Range dropping mid-call after a new Ni-MH pack goes in

Ni-MH batteries straight out of the box carry a partial charge — typically 40–60% of rated capacity. The EXP901 transmits at full RF power during a call, which draws more current than standby. If the pack is not fully conditioned, voltage sags under that RF load, and the handset drops transmit power to compensate. The result is reduced range even though the handset shows a full battery icon. Running two to three full charge-discharge cycles through the base station closes the gap and brings output voltage up to the level the RF circuit expects.

Base station showing no-charge or error light with a new battery installed

Ni-MH packs that have been in storage can drop below the voltage threshold the EXP901 base station uses to confirm a valid battery is present. Some base stations refuse to enter charge mode when the incoming voltage reads too low, triggering an error or no-charge indicator. To recover, leave the handset seated in the base for 30 minutes — the trickle circuit in most DECT bases will slowly raise the pack voltage to the acceptance threshold, after which normal charging begins. If the error light persists past 45 minutes, check that the handset contacts are clean and fully seated. Target pack voltage for charge acceptance on this base is approximately 3.0V or above.