About this replacement
Golf Buddy WT3 GPS Watch — 3.7V Li-Polymer Replacement Battery (AEE622530P6H)
This 3.7V, 550mAh Li-Polymer cell replaces part number AEE622530P6H in the Golf Buddy WT3 GPS Watch. The WT3 is a wrist-worn golf GPS device that displays real-time yardage and course data during a round. Voltage, connector type, and physical dimensions (33.70 × 26.22 × 6.10mm) match the original cell exactly.
- WT3 GPS Watch platform fit: The WT3 runs a dedicated golf GPS processor alongside a continuous course-tracking radio. Both draw from this single cell via a shared power rail — voltage tolerance and connector polarity must match the OEM spec precisely, which this cell does.
- Bench tested on actual hardware: We cycled this cell through the WT3's BMS handshake, confirmed charge acceptance from the magnetic dock, and verified the fuel gauge IC registered capacity correctly after a full charge cycle from near-zero.
- Post-swap charge protocol for the WT3: After fitting this cell, place the watch immediately on its magnetic charger and run it to 100% before first use. The WT3's fuel gauge IC loses its capacity reference when the original cell is removed — it cannot recalibrate without one complete charge cycle from near-zero on the new cell.
GPS radio current spikes and what they do to a small Li-Polymer cell
The WT3's GPS receiver pulls short, sharp current bursts each time it acquires or refreshes a satellite fix — this is normal GPS behaviour, but it stresses small-capacity cells more than steady draws do. A degraded original cell often struggles to hold voltage during these spikes, which the BMS reads as a low-voltage event and uses to trigger a shutdown. A fresh 550mAh cell at full charge handles these transient loads without the voltage sag that trips the cutoff. If the watch was shutting down mid-round on the old battery, this is the most likely cause.
Watch shows correct charge percentage then drops to 0% suddenly during a round
This is a fuel gauge IC drift fault, not a dead cell. The WT3's gas gauge tracks remaining capacity using accumulated charge and discharge data — when a worn cell's internal resistance rises, the gauge's model drifts away from reality. The watch then reads 80% until a GPS spike causes a voltage dip the gauge wasn't predicting, and it snaps to 0% and shuts down. Fitting a new cell fixes the resistance mismatch, but the gauge still needs one full charge-to-100% cycle before its readings stabilise — charge fully before taking the watch onto the course.