BlueNEXT BN-901 GPS Navigator Replacement Battery 3.7V 1000mAh

BlueNEXT BN-901 / BN-901S — 3.7V Li-ion Replacement Battery

This is a 3.7V, 1000mAh (3.7Wh) Li-ion battery for the BlueNEXT BN-901 and BN-901S portable GPS navigators. It replaces the original cell when capacity fades or the unit no longer holds a charge through a navigation session. Physical dimensions are 52.96 × 33.64 × 5.15mm — confirm these against your original cell before fitting.

• BN-901 and BN-901S compatibility: Both models share the same battery bay dimensions and 3.7V single-cell architecture. The BMS on these units monitors cell voltage directly — no proprietary handshake or authentication chip is involved, so swapping cells does not trigger a lock-out.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on a GPS navigator platform at 3.7V nominal. The BMS responded correctly at low-voltage cutoff, and charge acceptance held across multiple cycles without thermal events.
• First outdoor power-on after fitting: After installing this cell, power the unit on outside and let it acquire a satellite fix before driving. A full power interruption forces a cold start — the GPS receiver rebuilds its almanac from scratch, which takes 5–10 minutes for first lock versus under a minute on a warm start.

GPS accuracy reduced when battery level drops below 20%

The BN-901 series reduces receiver sensitivity at low battery to protect the cell from deep discharge. This shows up as position drift or a widened accuracy circle on the map — not a signal problem, a power management decision by the firmware. Keeping the battery charged above the low-voltage threshold prevents the receiver from throttling back. If accuracy issues appear mid-route, plug in via the car charger and the receiver sensitivity recovers within a few seconds.

Unit shuts off without warning before the battery indicator hits empty

The on-screen battery gauge on the BN-901 is calibrated to the original cell's discharge curve. A new cell — or a degraded original — can have a slightly different voltage slope, which causes the firmware to underestimate remaining capacity. The unit hits the hardware cutoff voltage before the visual indicator reaches zero. Run two or three full charge-to-discharge cycles after fitting the new battery; the firmware recalibrates its voltage-to-percentage mapping and the gauge becomes accurate again.