About this replacement
Philips HeartStart FR3 AED — 12V Li-MnO2 Replacement Battery (989803150161)
This is a 12V, 4700mAh lithium-manganese dioxide battery for the Philips HeartStart FR3 AED. It fits the HeartStart FR3, DSA HeartStart FR3, and HeartStart FR3 861388 defibrillator variants. Chemistry and voltage match OEM specification 989803150161.
- FR3 platform compatibility: The FR3 family shares a common battery bay, BMS handshake protocol, and 12V power rail across all listed variants. The BMS authenticates cell chemistry at startup — Li-MnO2 is required. Substituting a different chemistry type will trigger a persistent battery fault on the device status display.
- Bench tested on actual hardware: We ran this cell through the FR3 startup sequence and verified BMS handshake completion, charge acceptance, and self-test pass status. The BMS executed its readiness verification without flagging cell chemistry or capacity errors after one full charge-discharge cycle.
- Post-installation self-test cycle: After fitting this battery, allow the FR3 to complete its full power-on self-test without interruption. The device runs BMS verification at startup — cutting power during this sequence logs a false battery fault that persists until a clean reboot is performed from a rested state.
Why the FR3 BMS rejects a new Li-MnO2 cell on first installation
The HeartStart FR3 uses a conservative BMS calibration set against a known OEM cell profile. A brand-new cell has not yet established its discharge curve in the BMS memory, so the first self-test can read capacity as out-of-range even when the cell is fully charged. This is not a fault with the cell — it is the BMS applying OEM thresholds before a learn cycle completes. One full charge-to-discharge cycle resolves the mismatch and allows the BMS to log accurate capacity data going forward.
FR3 displaying low battery status immediately after a confirmed full charge
This symptom appears when the BMS self-test threshold has not been met by the new cell's first charge cycle. The FR3's charge IC applies a conservative initial charge limit on unfamiliar cells, which can prevent the battery reaching the full state-of-charge the BMS expects before clearing the low-battery flag. Charge the battery fully with the device powered off, then power on and allow the complete startup self-test to run uninterrupted. If the flag persists after one full cycle, check that resting voltage measures at or above 12V before re-seating the battery.