Edan SE-12 ECG Replacement Battery HYLB-727 14.4V 5200mAh

Edan SE-12 / SE-601 / SE-1202 ECG — 14.4V Li-ion Replacement Battery (HYLB-727)

This is a 14.4V 5200mAh lithium-ion battery for the Edan SE-12, SE-601, and SE-1202 electrocardiograph machines. These portable ECG units use a single internal pack to power acquisition, display, and transmission functions. Voltage and form factor match OEM part numbers HYLB-727, M21R-064114, TWSLB-004, and 21.21.064146.

• SE-12, SE-601, and SE-1202 compatibility: All three models share the same 14.4V battery bay, connector pinout, and BMS communication protocol. The charge IC in each unit expects the same thermistor response and cell-ID handshake, so one pack covers the full platform.
• Bench tested on actual hardware: We ran this pack through charge and load cycles on an SE-12 unit. The BMS accepted the cell profile without fault flags, and the charge IC reached full termination voltage without triggering a protection cutoff.
• Post-swap self-test requirement: After installing this battery, allow the device to complete its full power-on self-test without interruption. The ECG's BMS runs a verification routine at startup — cutting power mid-sequence logs a false battery fault that persists until the next complete reboot cycle.

SE-12 not completing boot sequence after battery swap

The SE-12 runs a hardware self-test during every boot that includes a BMS handshake with the installed pack. A new cell that hasn't completed one full charge-discharge cycle may return a state-of-health value outside the expected window, causing the device to stall at the initialisation screen. This isn't a defective battery — it's the charge IC applying conservative thresholds to an uncharacterised cell. Charge the pack fully, power on the device, and let it run through one complete clinical-load discharge before relying on it for patient use.

Charge indicator stalls below 100% on the first charge

The SE-12's charge IC uses a current-taper cutoff — it terminates the charge cycle when current drops to roughly 3% of the C-rate, not on a fixed timer. With a new cell, internal impedance is slightly elevated, so the taper threshold is reached before the pack reaches full capacity. The display may hold at 95–98% and stop climbing. One full cycle normalises cell impedance and the subsequent charge typically reaches 100%. If the indicator still stalls after three full cycles, check that the pack is seated fully and the terminal voltage at the connector reads at least 16.4V at charge termination.