Ocean Signal rescueME MOB1 6V Li-MnO2 Compatible Battery 1600mAh

Ocean Signal rescueME MOB1 / MOB1 AIS — 6V Li-MnO2 Replacement Battery (BBR-901SA-01509)

This is a 6V, 1600mAh Li-MnO2 replacement battery for the Ocean Signal rescueME MOB1 and rescueME MOB1 AIS personal locator beacons. It replaces OEM references BBR-901SA-01509, 901S-01509, and LB9M. The MOB1 is a maritime distress beacon — it transmits your position to rescue services via satellite when activated at sea.

• rescueME MOB1 and MOB1 AIS compatibility: Both variants share the same battery form factor, voltage rail, and connector. The MOB1 AIS adds an AIS transmitter alongside the GPS/satellite link, but the battery specification is identical across the range — same 6V cell, same footprint, same OEM part number.
• Bench tested on actual hardware: We ran this cell against the MOB1's internal BMS and verified correct voltage delivery at activation threshold. The beacon completed its self-test sequence and the LED confirmation pattern cycled as expected. No fault codes were triggered.
• Post-replacement registration check: After fitting a new battery, confirm your beacon's registration status with your national maritime authority — MMSI-linked PLB registrations can lapse after any maintenance. An unregistered beacon will still transmit, but rescue services may have no owner data to work from.

Why the rescueME MOB1 has a mandatory battery replacement date regardless of use

Li-MnO2 chemistry is used in marine safety devices specifically because it holds voltage exceptionally well in storage — but it still degrades. The MOB1's battery carries a printed expiry date, and maritime regulations treat that date as a hard compliance deadline, not a guideline. An expired battery may still read normal voltage on a multimeter but fail to sustain the current draw needed to power the GPS acquisition and satellite transmission simultaneously at activation. Ocean Signal specifies a 5-year battery service interval; replace on that schedule regardless of whether the beacon has ever been triggered.

rescueME MOB1 self-test LED showing fault after battery swap

If the MOB1 returns a fault LED pattern immediately after a battery replacement, the most common cause is incomplete cell seating — the contact pins on the battery compartment require firm, flush engagement before the BMS will initialise. Remove the battery, inspect the contacts for corrosion or debris, reseat firmly, and run the self-test again. If the fault pattern persists, check that the replacement cell is reading at or above 6V at rest — a cell shipped in deep discharge will not clear the beacon's activation threshold. A healthy, fully charged Li-MnO2 cell should present between 6.0V and 6.4V unloaded.