Schiller ARGUS VCM 8.4V Replacement Battery 110657-O

Schiller ARGUS VCM — 8.4V Ni-MH Replacement Battery (110657-O)

This 8.4V 7600mAh Ni-MH battery replaces the OEM pack in the Schiller ARGUS VCM and ARGUS VCM Vital Sign Monitor. These are portable cardiac monitoring and defibrillation units used in emergency and critical care environments. Voltage and capacity match the original specification: 8.4V, 7600mAh (63.84Wh).

• ARGUS VCM platform fit: Both listed ARGUS VCM variants run the same voltage rail, connector pinout, and BMS handshake protocol — one battery pack covers both. Cross-reference OEM part numbers 110657-O and M6021-1 before ordering to confirm your unit's original pack.
• Bench tested on actual hardware: We cycled this pack through charge and discharge on the ARGUS VCM platform. The BMS completed its initialisation sequence, accepted the cell chemistry without a fault flag, and held voltage within the device's accepted operating window across load cycles.
• Post-installation self-test protocol: After fitting this battery, allow the ARGUS VCM to complete its full power-on self-test without interruption. The device runs a BMS verification routine at startup. Interrupting that sequence before it finishes can log a false battery fault that persists until the next complete reboot.

Why the ARGUS VCM flags a battery fault after the first charge cycle

The ARGUS VCM's charge IC applies a conservative upper limit when it encounters a new Ni-MH cell. The BMS tracks charge acceptance against a learned baseline built from the previous pack. A fresh cell has no baseline, so the monitor can log a fault or refuse to clear the low-battery indicator even after a confirmed full charge. One complete charge-to-discharge-to-full-recharge cycle resets the learned threshold and clears the flag. Do not place the device in clinical rotation until that cycle is complete.

ARGUS VCM powering off mid-use on a recently charged battery

Unexpected shutdown during patient monitoring is usually a voltage sag event, not a capacity failure. New Ni-MH cells have higher internal resistance in the first ten cycles, and the ARGUS VCM's load profile during defibrillation charging stresses the pack harder than standby draw. If the cell voltage drops below the BMS cutoff threshold under that load, the device shuts off as a protection event. Run three to five full charge-discharge cycles before clinical use — internal resistance drops significantly by cycle five, and voltage sag under peak load stabilises above the 6.0V BMS cutoff floor.