Fukuda EK-168G ECG Compatible Battery FL-1A 3.7V 1200mAh

Fukuda EK-168G / EK-268G / EK-468G — 3.7V Li-ion Replacement Battery (FL-1A)

This 3.7V 1200mAh Li-ion battery replaces the FL-1A pack in the Fukuda EK-168G, EK-268G, and EK-468G portable electrocardiographs. These are compact ECG machines used in clinics, field cardiac surveys, and mobile diagnostic workflows. Capacity is 4.44Wh at the cell level — matching the original pack specification.

• EK-168G / EK-268G / EK-468G platform fit: All three models share the same battery bay geometry, connector pinout, and BMS handshake protocol. The FL-1A form factor — 53.00 × 33.90 × 5.70mm — is consistent across the series, so one replacement covers all three machines.
• Bench tested on actual hardware: We ran this pack through full charge and discharge cycles, monitoring BMS communication with the ECG unit. The protection circuit responded correctly to charge termination and low-voltage cutoff. No false low-battery flags appeared during sustained acquisition runs.
• Post-install calibration on the EK series: After fitting a new pack, run a complete system calibration sequence through the EK's onboard menu before your first patient session. The ECG firmware maps battery state during calibration — skipping this step causes premature low-battery warnings to fire partway through your first recording session, even when the pack is near full charge.

BMS lockout on the FL-1A after the EK sat unused in a carry case

Li-ion cells self-discharge during storage. If the EK-168G sits unused for several months, the pack can drop below the BMS recovery threshold — typically around 2.5V per cell. At that point the protection circuit latches into sleep mode and the unit will not power on or accept a charge signal. A standard charger sees no load and stops the charge attempt within seconds. To recover, use a charger with a trickle or recovery mode that can push a low current — around 50–100mA — until cell voltage climbs above 3.0V, at which point the BMS re-initialises and normal charging resumes.

EK-168G shuts down mid-recording with no low-battery warning

This is a voltage sag issue, not a capacity issue. During an active ECG acquisition, the analogue front-end and display draw current simultaneously — if the cell's internal resistance has climbed with age, terminal voltage drops sharply under that combined load. The BMS reads this transient sag as an undervoltage condition and trips the output. The machine goes dark mid-trace, with no warning beforehand because the resting voltage looked fine. Fitting a fresh FL-1A cell with low internal resistance eliminates the sag — confirm the pack is fully charged to 4.2V before the session.