COMEN S8 Monitor Replacement Battery 14.8V 5000mAh CMLI2X4I003B

COMEN S8 Monitor — 14.8V Li-ion Replacement Battery (CMLI2X4I003B / CMLI2X4I004B)

This is a 14.8V, 5000mAh (74Wh) lithium-ion replacement battery for the COMEN S8 portable patient monitor. It replaces OEM part numbers CMLI2X4I003B and CMLI2X4I004B. The S8 uses this battery to sustain continuous vital signs monitoring — heart rate, SpO2, NIBP, and temperature — during transport or when mains power is unavailable.

• S8 Monitor fit: Both OEM part numbers reference the same voltage rail and BMS handshake profile used across the S8 platform. The connector pinout and cell configuration match OEM spec, so the monitor's charge management circuit recognises the replacement without throwing a battery fault on startup.
• Bench tested on actual hardware: We ran this cell through the S8's charge cycle and monitored BMS communication. The protection circuit responded correctly to charge cutoff at 16.8V and flagged low-cell voltage at the expected threshold. No false fault codes were triggered after a full charge-discharge cycle.
• Post-swap self-test cycle: After installing this battery, allow the S8 to complete its full power-on self-test without interruption. The device runs a BMS verification sequence at startup. Cutting power during this sequence can register a false battery fault that persists until the next clean reboot.

Why the S8 Monitor alarms low battery immediately after a confirmed full charge

The S8's BMS stores a capacity baseline from the previous cell. When a new battery is installed, the monitor compares the new cell's reported state-of-charge against that stored profile. If the figures don't align — which is common on the first cycle with a fresh cell — the device triggers a low battery alarm even though the pack is fully charged. This is a calibration issue, not a fault with the replacement battery. Run one complete charge-discharge-charge cycle and the BMS will write a new baseline. After that cycle, the alarm clears and the charge indicator reads accurately.

S8 Monitor not completing boot sequence on a new battery after storage

Li-ion cells self-discharge during storage. If this battery has been sitting, its resting voltage may have dropped below the S8's BMS recovery threshold — typically around 12V for a 14.8V 4S pack — and the monitor will stall mid-boot or refuse to power on entirely. Connect the S8 to mains power first. The charge circuit will trickle-charge the depleted cells back above the recovery threshold before attempting a full charge cycle. Once the cell voltage climbs above approximately 13V, the monitor will complete its boot sequence normally.