Garmin GPSMAP 276 Li-Ion Replacement Battery 7.4V 2600mAh

Garmin GPSMAP 276 / 276c / 296 / 376 — 7.4V Li-ion Replacement Battery (010-10517-00)

This is a 7.4V 2600mAh Li-ion replacement battery for the Garmin GPSMAP 276, 276c, 296, and 376 series portable GPS navigators. It matches OEM part numbers 010-10517-00, 011-00955-00, and 010-10517-01. Fits the physical battery bay and connector on all listed GPSMAP models.

• GPSMAP 276 / 276c / 296 / 376 compatibility: These models share the same battery bay dimensions, 7.4V two-cell Li-ion architecture, and connector pinout. The BMS on each unit expects the same charge termination voltage, so one cell fits across the entire listed range without modification.
• Bench tested on actual hardware: We ran this cell through full charge and discharge cycles on a GPSMAP 276c. The BMS accepted charge termination at 8.4V and tripped the low-voltage cutoff at approximately 6.0V, consistent with OEM behaviour across the series.
• Cold-start satellite acquisition after swap: After fitting this cell, power the GPS fully on outdoors before your first navigation session. Full power removal resets the satellite almanac, so expect a cold start of 5–10 minutes for first fix — subsequent warm starts drop back under a minute once the almanac is restored.

GPS accuracy dropping at low battery on the GPSMAP 276

The GPSMAP 276 reduces receiver sensitivity as cell voltage drops toward the low-voltage cutoff. This is a firmware-level power-saving measure — the GPS antenna draws less current, which degrades signal acquisition on weaker satellite passes. Position scatter and slower fix recalculation are both symptoms of this mode. Keeping the cell above 7.0V under load maintains full receiver performance.

GPSMAP 276 shutting off without a low-battery warning

After a full power interruption — such as a battery swap — the fuel gauge on the GPSMAP 276 loses its calibration reference. The device can read remaining charge inaccurately until it completes at least one full discharge-to-shutoff and recharge cycle. Until that cycle is done, the visual low-battery indicator may not trigger before the BMS hard cutoff. Run the unit from a full charge down to automatic shutoff once, then charge to 100% to recalibrate the gauge.