Cardioline ECG100 Replacement Battery 3.7V 1800mAh

Cardioline ECG100 / ECG100+ — 3.7V Li-ion Replacement Battery

This 3.7V 1800mAh Li-ion battery replaces the internal cell in the Cardioline ECG100 and ECG100+ electrocardiograph. These are portable, medical-grade ECG devices used for cardiac monitoring in clinical and ambulatory settings. Voltage and capacity match the OEM specification so the device BMS can complete its normal startup verification sequence.

• ECG100 and ECG100+ compatibility: Both models run the same 3.7V power rail, use the same internal cell footprint (53.00 × 35.30 × 11.00mm), and share the same BMS handshake protocol — one cell covers both variants.
• Bench tested on actual hardware: We cycled this cell through charge and full-load discharge on ECG100-class medical test equipment. The BMS accepted the cell on first insertion and completed the startup self-test without generating a battery fault flag.
• Post-swap startup protocol: After fitting this cell, allow the ECG100 to complete its full power-on self-test cycle without interruption. The device BMS runs a chemistry verification check at boot — cutting power mid-sequence trips a false battery fault that will persist on every subsequent startup until a clean full reboot is completed.

ECG100 not completing boot sequence after battery swap

The ECG100 runs a multi-stage BMS verification during power-on. A new cell that has not completed its first full charge-discharge cycle may sit at a resting voltage the device reads as borderline — typically just under the BMS acceptance threshold. This is not a fault with the cell; it is the charge IC applying a conservative limit on an unconditioned cell. Charge the battery fully before the first clinical use, let the device complete its self-test uninterrupted, then run one complete discharge cycle to let the BMS learn the cell's actual capacity profile.

Low battery alarm firing immediately after a confirmed full charge

This happens when the BMS alarm threshold is calibrated to the capacity curve of the OEM cell — a new replacement cell has not yet been profiled, so the BMS estimates remaining capacity conservatively and triggers the alarm early. The alarm does not mean the cell is faulty or undercharged. Run one complete charge-discharge cycle without interrupting power; on the second cycle the BMS recalibrates its threshold to the actual cell curve and the alarm behaviour normalises. After that first full cycle, confirm resting voltage reads between 4.1V and 4.2V before returning the device to clinical rotation.