Spring ECG-902A Replacement Battery 14.4V 2600mAh Li-ion

Spring ECG-902A — 14.4V Li-ion Replacement Battery (ICR18650-4X)

This is a 14.4V, 2600mAh Li-ion battery pack for the Spring ECG-902A portable electrocardiogram monitor. It replaces the ICR18650-4X cell pack used to power the device during cardiac examinations and patient data recording. Restore full function to units where the original pack no longer holds charge or fails the device self-test.

• ECG-902A compatibility: The ECG-902A runs a 14.4V bus with a four-cell Li-ion configuration. This pack matches that voltage rail, connector pinout, and the BMS communication protocol the device expects at startup. No hardware modification needed.
• Bench tested on actual hardware: We cycled this pack through charge and discharge on the ECG-902A platform. The onboard BMS negotiated correctly, charge termination triggered at the expected threshold, and the device passed its power-on self-test without fault flags on the second full cycle.
• Post-swap startup sequence: After installing this pack, let the ECG-902A complete its full power-on self-test without interruption. The device runs a BMS verification routine at boot — cutting power during this sequence writes a battery fault to memory that persists until the next clean reboot, even if the pack itself is fine.

ECG-902A not completing boot sequence on a new battery

The ECG-902A runs a self-test at startup that queries the battery BMS for state-of-charge and cell health data. A fresh Li-ion pack hasn't yet completed a calibration cycle, so the BMS may return a state-of-charge estimate outside the device's expected window. This trips a boot fault and halts the startup sequence before the device reaches the home screen. Run one full charge from flat to termination, then power on — after that first cycle, the BMS estimate stabilises and the device boots cleanly.

Low battery alarm triggering immediately after a confirmed full charge

This happens because the ECG-902A's low-battery threshold is calibrated to OEM cell chemistry, and a new replacement pack needs one full charge-discharge cycle before the BMS learns its actual capacity baseline. On the first charge, the charge IC applies a conservative current limit, and the reported state-of-charge can read lower than the actual cell voltage supports. Discharge the pack fully through normal device use, then charge to termination. After that conditioning cycle, the alarm threshold and the pack's reported charge should align — check that resting voltage reads above 16.0V after a full charge before concluding there is a fault.