EDANINS ECG-3B Compatible Battery 11.1V 1800mAh Li-Polymer

EDANINS ECG-3B / BPM-E305 — 11.1V Li-Polymer Replacement Battery

This 11.1V, 1800mAh lithium-polymer battery replaces the internal power cell in the EDANINS ECG-3B portable electrocardiograph and BPM-E305 blood pressure monitor. Both devices run on the same 11.1V three-cell Li-Polymer pack with matched connector and BMS handshake. Capacity is rated at 19.98Wh.

• ECG-3B and BPM-E305 compatibility: Both units share an identical 11.1V three-cell architecture, the same JST-style connector pitch, and the same BMS communication protocol. One cell fits both without adapter or modification.
• Bench tested on actual hardware: We cycled this cell through charge, standby, and discharge under the ECG-3B load profile. The BMS registered cell voltage correctly, accepted the charge IC handshake, and triggered no protection faults across the first three cycles.
• Power-on self-test after swap: After installing this battery, let the ECG-3B complete its full startup self-test without pressing any buttons or interrupting the boot sequence. The device runs BMS verification at power-on — cutting it short flags a false battery fault that sticks until the next clean reboot.

Why the ECG-3B reports a battery fault on a brand-new cell

The ECG-3B BMS stores a learned capacity profile from the previous cell. When a new cell is installed, the measured discharge curve does not yet match the stored model, so the device flags a mismatch fault. This clears after one complete charge-discharge cycle. Run the battery to the device's low-battery cutoff, then charge fully to 12.6V before clinical use.

Charge indicator stalling below 100% on first charge

On a new Li-Polymer cell, the charge IC applies a conservative current limit during the first top-up cycle. This makes the indicator appear to stall at 85–95% when the cell is still absorbing charge normally. The cell is not defective. Allow the charge cycle to run to termination without removing the device from the charger — the indicator will reach full on cycle two. Confirm full charge by checking that the ECG-3B shows 12.4V or above at the battery status screen.