Minelab Eureka Gold Replacement Battery 12V 1200mAh

Minelab Eureka Gold / Sovereign Series — 12V Ni-MH Replacement Battery (3011-0215)

This is a 12V 1200mAh Ni-MH replacement for OEM part number 3011-0215. It fits the Minelab Eureka Gold, Sovereign GT, Sovereign Elite, and Musketeer Advantage metal detectors. Voltage and pack format match the original specification exactly.

• Eureka Gold and Sovereign platform fit: These four detectors share the same 12V battery housing, connector, and charge management circuit. The same pack architecture carries across the Sovereign GT, Sovereign Elite, and Musketeer Advantage because Minelab standardised the voltage rail and physical format across this detector generation.
• Bench tested on actual hardware: We ran this pack through charge and discharge cycles on a Minelab-compatible test rig. The BMS held cutoff voltage cleanly and the pack accepted a full charge without thermal event or protection trip under normal detector load.
• Detector storage between seasons: If the detector has sat unused for several months, charge the pack fully before the first outing. Ni-MH cells self-discharge at roughly 1–2% per day at room temperature, and a partially discharged pack left in storage can drop below the level the detector's charge circuit will accept without a conditioning cycle first.

Why the Eureka Gold cuts out during a sweep when the battery indicator still shows charge

The Eureka Gold's detector circuit draws a short current spike each time the transmit coil fires. On an aged or partially discharged Ni-MH pack, internal resistance has risen enough that this spike pulls the terminal voltage below the detector's cutoff threshold — even if the indicator was reading mid-range a moment earlier. The pack isn't empty; it just can't sustain the instantaneous load. A freshly charged replacement pack with lower internal resistance handles the spike without dropping out.

Pack won't take a charge after sitting unused in the carry case for months

Ni-MH cells that have self-discharged deeply enough can drop below the voltage floor the standard Minelab charger uses to confirm a valid pack is connected. The charger reads the low voltage as an error condition and stops before delivering any current. To recover the pack, apply a slow trickle charge at around 60–100mA from a universal Ni-MH charger until terminal voltage climbs above 10V, then switch to the standard charger. If the pack doesn't respond after 30 minutes of trickle input, the cells have reached end of life and replacement is the correct next step.