About this replacement
XP Metal Detectors WS6 / WSAII / WS4 Series — 3.7V Li-Polymer Replacement Battery (D088WS-WTUBE)
This 3.7V, 250mAh Li-Polymer cell replaces the D088WS-WTUBE battery in XP Metal Detectors wireless audio headsets. It fits the WS6, WSAII, WS4, and WS audio headphone models. At 31.20 x 20.00 x 4.50mm, the cell matches the original footprint inside the compact headset housing.
- WS6 and WSAII headset compatibility: These models share the same 3.7V power rail, connector pinout, and BMS handshake protocol — which is why a single cell part number covers the full wireless headset range. Swapping to a different voltage or cell format breaks the charge-termination signal the base station relies on.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on the bench, monitoring BMS cutoff behaviour under combined audio driver and DECT radio draw. Voltage held stable through the operating window and the protection circuit triggered cleanly at the low-voltage threshold.
- First charge in the base station: Place the headset in the XP base station and let it complete a full charge cycle before using it in the field. The base station logs the new cell during this cycle — without it, the talk-time indicator reads incorrectly and the headset may cut out earlier than expected.
Base station not recognising the new pack after a cell swap
XP wireless headsets use a BMS handshake — the base station polls the cell's protection circuit before it begins a charge cycle. If the headset sits unused for weeks before installation, the cell may drop to storage voltage, which some base firmware reads as a fault rather than a depleted pack. The fix is to hold the headset in the cradle for at least 15 minutes before removing it; the trickle stage brings the cell above the recognition threshold. Once the charging LED shifts from fault to active, the cycle completes normally.
Headset cutting out mid-session on a fresh cell
This usually points to voltage sag under the combined load of the audio driver and DECT radio transmitter — not a faulty cell. In a housing this small, peak draw during active transmission can momentarily pull voltage below the BMS low-voltage cutoff, especially in the first few cycles before the cell has conditioned. Run three to five full charge-and-use cycles and the sag window narrows as the cell reaches stable capacity. If cut-outs persist past five cycles, check the headset connector for oxidation — a resistive contact amplifies sag at the same draw level.