About this replacement
Schiller Cardiograph CV3 / CV6 — 9.6V Ni-MH Replacement Battery (110071)
This 9.6V 2000mAh Ni-MH battery replaces part number 110071 in the Schiller Cardiograph CV3 and CV6 portable electrocardiograph units. These devices are used for clinical ECG recording and cardiac rhythm analysis in both facility and ambulatory settings. Voltage, connector, and BMS handshake match the OEM specification.
- CV3 and CV6 platform compatibility: Both models share the same 9.6V Ni-MH battery architecture, connector pinout, and BMS communication protocol — one cell fits both units without modification or adapter.
- Bench tested on actual hardware: We cycled this cell through full charge and discharge on a CV3 unit. The BMS completed its self-test handshake and accepted the cell on first insertion. Charge IC behaviour was consistent with OEM cell response.
- Post-swap self-test protocol: After fitting this battery, allow the CV3 or CV6 to complete its full power-on self-test without interruption. Cutting power during this sequence causes the BMS to log a battery fault that persists until the next clean reboot — even if the cell is fully charged.
Why the CV3 alarms low battery immediately after a confirmed full charge
The CV3's BMS uses a learned capacity threshold calibrated to the OEM cell's internal resistance profile. A new replacement cell has a slightly different resistance signature on the first cycle, which the BMS interprets as a low-state cell rather than a new one. This triggers a low battery alarm even when the cell is at full charge. Running one complete charge-discharge cycle allows the BMS to recalibrate its threshold to the new cell. After that cycle, the alarm clears and normal operation resumes.
CV3 will not power on after battery sat in storage
Ni-MH cells self-discharge during storage — a cell stored for several months can drop below 8.5V, which is below the CV3's BMS recovery threshold. At that voltage the BMS treats the pack as faulted and blocks power-on entirely. Place the battery on charge for a full uninterrupted cycle before reinserting it. If the charger fails to initiate on a deeply discharged cell, check that the cell resting voltage reads above 7.0V before attempting recovery.