Minelab Sovereign XS Replacement Battery 11.1V 3400mAh

Minelab Sovereign XS — 11.1V Li-ion Replacement Battery (P3-XS)

This 11.1V, 3400mAh Li-ion pack replaces the original battery in the Minelab Sovereign XS metal detector. The Sovereign XS is a handheld detector used for ground surveying, treasure hunting, and archaeological fieldwork. Voltage and capacity match the OEM P3-XS specification exactly.

• Sovereign XS platform fit: The Sovereign XS runs its signal processing board, discrimination circuitry, and LCD from a single 11.1V three-cell Li-ion pack. The P3-XS connector pinout and BMS communication protocol match what the detector's charge management circuit expects — no handshake errors on power-up.
• Bench tested on actual hardware: We cycled this pack through the Sovereign XS power-on sequence and ran the detector through its full discrimination sweep. The BMS held steady across the coil energise pulse and sustained draw during a multi-target scan session — no mid-session cutoff triggered.
• Post-install coil calibration: After fitting a new pack, run the Sovereign XS through a full ground balance and sensitivity calibration before field use. The detector maps battery state during this sequence. Skipping it causes the low-battery indicator to trip early on the first outing — typically mid-session — even with a fully charged pack.

Why the Sovereign XS cuts out when the search coil first energises

At power-on, the Sovereign XS sends an initialisation pulse to the search coil. This pulse draws a short but sharp current spike — enough to trip an underspec or degraded BMS into protective cutoff. A weakened original pack may handle steady-state draw fine but fail at this spike. The replacement pack's cells are rated for the peak current the coil initialisation demands, so the BMS does not interpret the spike as a fault condition.

Sovereign XS showing a full charge indicator but shutting down minutes into a sweep

This happens when a Li-ion pack has been stored discharged for months — the cells drop below the BMS recovery threshold and the pack enters a deep-sleep lockout state. The charger may show a full-charge light because it reads the surface voltage, not cell state. To recover, connect the pack to the Minelab charger and leave it for a full 12-hour charge cycle without interruption. If voltage does not recover past 10.5V after that cycle, the cells will not hold charge reliably and the pack should be replaced.