About this replacement
COMEN CM600 Patient Monitor — 14.4V Li-ion Replacement Battery (JHT-99K-00)
This is a 14.4V, 3400mAh (48.96Wh) Li-ion replacement battery for the COMEN CM600 portable patient monitor. It matches the OEM part number JHT-99K-00 and fits both the CM600 and CM-600 variants. The battery slots into the same compartment as the original and connects to the same BMS handshake circuit.
- CM600 and CM-600 compatibility: Both model designations share the same 14.4V power rail, battery bay dimensions, and BMS communication protocol. The JHT-99K-00 part number covers both. No adapter or wiring change is needed.
- Bench tested on actual hardware: We ran this cell through a full charge-discharge cycle on the CM600 platform. The BMS completed its voltage verification handshake, charge current tapered correctly at top of charge, and the device exited standby without fault codes.
- Post-installation self-test protocol: After fitting this battery, let the CM600 complete its full power-on self-test without interrupting it. The device runs a BMS verification routine at startup. Cutting power during that sequence triggers a battery fault flag that stays latched until the next clean reboot cycle.
Why the CM600 shows a battery fault after a confirmed full charge
The CM600's BMS stores a learned capacity profile from the previous cell. A fresh replacement starts with no cycle history, so the BMS applies a conservative acceptance threshold on the first charge. The device may flag a fault even when the cell is genuinely at full charge. Run one complete charge-discharge cycle and the BMS recalibrates its threshold to the new cell's actual capacity. After that cycle, the fault clears and the charge indicator reads correctly.
CM600 won't power on after battery sat in storage
Li-ion cells self-discharge during storage. If the cell voltage drops below the CM600's BMS recovery threshold — typically around 10V on a 14.4V pack — the BMS locks out discharge entirely as a protection measure. Connect the battery to the charger and leave it for at least 30 minutes before attempting to power on. Most BMS circuits re-enable discharge once the cell climbs above the recovery threshold, usually 12.0V to 12.5V on this pack.