About this replacement
Globalstar TR-150 / TR-151 — 3.7V Li-Polymer Replacement Battery (ATL903857)
This 3.7V 2000mAh Li-Polymer cell replaces the original ATL903857 battery in the Globalstar TR-150 and TR-151 satellite communicators, including Telenav-branded variants. These devices operate in remote areas with no cellular coverage, so a dead battery is not a minor inconvenience — it cuts off GPS tracking, two-way messaging, and emergency communication. Voltage and capacity match the OEM spec at 3.7V / 7.4Wh.
- TR-150 and TR-151 platform fit: Both models share the same battery bay dimensions, connector pinout, and BMS handshake protocol. The ATL903857 cell also cross-references to GT920 and BP02-000540, covering all known board revisions across the TR-150 and TR-151 production runs.
- Bench tested on actual hardware: We cycled this cell through charge, standby, and active satellite-messaging loads. The BMS held stable voltage across all three states with no false low-battery flags or unexpected cutoffs during message transmission bursts.
- Cold-start reset after swap: After fitting this cell, power the TR-150 fully on outdoors and let it acquire a satellite fix before heading into the field. GPS performs a cold start after any full power removal — first fix can take 5–10 minutes. Once acquired, subsequent warm starts are under a minute.
Active navigation draining the TR-150 faster than standby
The TR-150 runs its GPS receiver, satellite modem, and display simultaneously during active navigation. That combined draw is significantly higher than standby, where only the modem polls periodically. Screen brightness is the fastest lever — dropping it one or two steps cuts display load noticeably without affecting readability outdoors. Turning off tracking intervals you don't need also reduces modem transmit cycles and extends usable charge.
TR-150 shuts off without a low-battery warning
This happens when the fuel gauge calibration drifts after a full power removal — the device's voltage threshold indicator loses its reference point and shows more charge than the cell actually holds. The fix is a full recalibration cycle: charge the unit uninterrupted to 100%, then run it through a complete discharge under normal use. After one full cycle the indicator re-anchors to the cell's actual voltage curve, and the low-battery warning will fire before the unit hits the 3.0V cutoff floor.