About this replacement
BlueParrott S450 / S450-XT — 3.7V Li-Polymer Replacement Battery (PL363450)
This is a 3.7V 700mAh Li-Polymer replacement battery for the BlueParrott S450 and S450-XT wireless headsets. It uses OEM part number PL363450 and matches the original cell format at 51.00 x 33.80 x 4.00mm. Fit it when the original battery no longer holds charge through a full shift.
- S450 and S450-XT compatibility: Both headset variants run the same 3.7V power rail, use the same connector, and accept the same BMS handshake — one cell covers both. No hardware difference between the two when it comes to the battery bay.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the S450 platform. The BMS completed its handshake with the base station without error, and the protection circuit triggered correctly at the low-voltage cutoff threshold.
- First cycle in the base station: Place the headset in the charging cradle and let it complete a full uninterrupted charge before making any calls. The base station logs the new cell during this cycle — without it, the talk-time indicator will read inaccurately for several sessions.
Why the S450 cuts out mid-call even with a charged battery
The S450 draws current from two systems simultaneously — the audio processor and the Bluetooth radio. During a call, that combined draw spikes briefly above what a degraded or unconditioned cell can sustain. Voltage sags below the BMS cutoff threshold, and the headset drops. A new cell will handle the combined draw, but if the first full charge cycle wasn't completed in the base station, the BMS may still log a low-capacity state and cut out prematurely. Complete that first full cycle before use.
Base station shows full charge but headset dies after a few minutes
A replacement cell arrives at storage voltage — typically around 3.6V — not at a calibrated full charge. The base station can misread this as a charged pack before the BMS has completed its first proper cycle. The headset then cuts off quickly because the cell hasn't been fully initialised. Seat the headset in the cradle and charge it uninterrupted to 4.2V before the first use — after that cycle, the base station and headset firmware align on the actual cell state.