Aricon ECG-3D Replacement Battery 11.1V 1800mAh XLD1306-03

Aricon ECG-3D / ECG-3B / SE-3B — 11.1V Li-Polymer Replacement Battery (XLD1306-03)

This 11.1V, 1800mAh Li-Polymer battery replaces the original power cell in the Aricon ECG-3D, ECG-3B, and SE-3B portable electrocardiogram monitors. It matches OEM part numbers XLD1306-03, XLD1305-03, BAT-141015200-041, BAT-190618270-152, and BAT-210506371-178. Capacity is 1800mAh (19.98Wh) — identical to the factory specification.

• ECG-3D, ECG-3B, and SE-3B compatibility: These three models share the same 11.1V three-cell Li-Polymer architecture, connector pinout, and BMS handshake protocol. The same physical cell and communication interface works across all three variants, which is why they share multiple OEM part numbers in Aricon's own documentation.
• Bench tested on actual hardware: We ran this cell through charge, standby, and load cycles on ECG-3D hardware. The BMS authenticated the cell without error flags, the charge IC brought it to full voltage without truncating the cycle, and the device passed its power-on self-test sequence on each boot.
• Post-swap startup procedure: After fitting the new battery, let the ECG-3D complete its full power-on self-test without interruption. The device runs a BMS verification pass at boot — cutting power mid-sequence forces a false battery fault that persists until the next clean reboot from a fully charged state.

ECG-3D not completing its boot sequence on a new battery

The ECG-3D boot sequence includes a battery chemistry verification step where the BMS compares cell impedance against stored OEM thresholds. A new Li-Polymer cell that has not yet completed its first full charge-discharge cycle presents slightly higher internal impedance than a conditioned cell. If the device stalls at boot or throws a battery fault on the first startup, run one complete charge cycle to 11.1V before powering on again. That single cycle is usually enough for the BMS to accept the cell and clear the fault flag.

Charge indicator not reaching 100% on first charge after swap

The ECG-3D charge IC applies a conservative current ceiling on cells it hasn't profiled yet, which means the first charge cycle may terminate early and show 90–95% on the display. This is a charge IC behaviour, not a faulty cell. Run the device down to the low-battery threshold under normal use, then recharge fully. After that conditioning cycle, the charge IC recalibrates its termination point and the display reads accurately at 100%.