About this replacement
RCA 25111 / 25270 Series — 3.7V Li-Polymer Replacement Battery (T-T101)
This is a 3.7V, 280mAh lithium-polymer cell that replaces the OEM T-T101 battery in RCA DECT wireless headsets. It fits the 25111, 25270, 25211, and 25065 models. Swap it in when the original cell no longer holds a charge or the headset cuts off unexpectedly during calls.
- 25111 / 25270 / 25211 / 25065 compatibility: These four RCA headset models share the same 3.7V rail, T-T101 connector footprint, and BMS handshake protocol. One cell covers the group — no wiring changes or adapters needed.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on a DECT headset platform. The BMS accepted the pack without error flags, and the protection circuit responded correctly to both charge termination and low-voltage cutoff events.
- Base station first-cycle logging: On first use, seat the headset in the base and let it complete one full charge cycle before taking a call. DECT base stations log the new cell during that first cycle — until it completes, the talk-time estimate on the base display will read inaccurate.
Base station not recognising the new pack after swap
When a replacement cell arrives at storage voltage — typically around 3.6V — some RCA base stations flag a charging error or show no charge activity at all. The base expects the cell voltage to rise within a set window after contact; a cold storage cell can fall outside that window. Place the headset on the base, leave it undisturbed for 20–30 minutes, and the BMS will usually complete the handshake once the cell climbs past 3.65V. If the base still shows an error, remove the headset for 10 seconds and re-seat it to trigger a fresh recognition cycle.
Headset cuts out mid-call even with a recently charged battery
The 25111-series headset draws current from two loads simultaneously — the audio circuit and the DECT radio transmitter. Under that combined draw, a cell that is partially degraded or still in its first few conditioning cycles can sag below the BMS cutoff threshold and trip the protection circuit. This is not a fault in the replacement cell; it is a normal response to voltage sag. Run three to five full charge-and-discharge cycles through the base station, and the cell's internal resistance will drop, reducing sag under load. After conditioning, mid-call cutouts caused by sag should stop.