SkyGolf SG1 GPS Navigator Replacement Battery 3.7V 1050mAh

SkyGolf SG1 / SG2 Series — 3.7V Li-ion Replacement Battery (GP50301HG026)

This 3.7V, 1050mAh lithium-ion cell replaces the factory battery in the SkyGolf SG1, SG2, SG2-USB, and SG0003 handheld golf GPS navigators. It matches the original GP50301HG026 specification and fits the same footprint at 51.19 × 36.04 × 5.54mm. Swap it in when the original cell no longer holds enough charge to complete a full round.

• SG1 / SG2 platform fit: The SG1 and SG2 series share the same battery bay dimensions, connector pinout, and BMS handshake protocol — that is why one cell covers the full range. The GP50301HG026 part number is consistent across those variants, and the BMS accepts this cell without requiring a firmware prompt or recalibration step.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on a GPS navigator test rig. The BMS held the charge cutoff at 4.2V and triggered the low-voltage protection at 3.0V without nuisance tripping during GPS receiver polling spikes.
• Cold-start satellite acquisition after fitting: After any full power removal, the SG1 loses its ephemeris data and must complete a cold start. Power the unit on outdoors in an open area and leave it stationary — first satellite fix typically takes 5–10 minutes. Subsequent power cycles warm-start in under a minute once the almanac is rebuilt.

GPS accuracy dropping at low battery on the SG1

When cell voltage falls below roughly 3.5V, some SkyGolf SG1 units reduce GPS receiver polling rate to conserve power. This shows up as course position that refreshes slowly or jumps between shots. The fix is not a software setting — it is a voltage issue. Keep the cell above 3.6V during a round by charging fully before you tee off.

SG1 shutting off without a low-battery warning

The SG1 fuel gauge reads the cell's state of charge against a calibrated discharge curve stored from the original battery. A new cell with a slightly different internal resistance can cause the gauge to read capacity optimistically, then hit the hardware cutoff voltage without triggering the on-screen warning. To recalibrate, run the unit from a full 4.2V charge down to auto-shutoff twice — the gauge re-maps the curve against the new cell's actual characteristics after two full cycles.