About this replacement
Verathon BladderScan 9400 / BVI 9400 — 11.1V Li-ion Replacement Battery (0400-0066)
This is an 11.1V 6800mAh Li-ion battery for the Verathon 9400 BladderScan and BVI 9400 portable ultrasound device. It replaces OEM part numbers 0400-0066, 0400-0121, and 0570-0066. The BladderScan uses this cell to power its ultrasonic transducer, display, and onboard processing during non-invasive bladder volume assessments.
- 9400 BladderScan and BVI 9400 fit: Both models share the same 11.1V three-cell Li-ion configuration, physical form factor, and BMS handshake protocol. A single replacement covers either unit without modification.
- Bench tested on actual hardware: We cycled this battery through the BladderScan's full power-on self-test sequence. The BMS negotiated correctly, accepted a full charge, and delivered stable voltage across the device's scan and display load.
- Power-on self-test after installation: After fitting this battery, let the device complete its full startup self-test without interruption. Medical-grade BMS firmware runs a verification pass at boot — cutting power mid-sequence logs a false battery fault that persists until the next clean reboot.
BladderScan charge indicator not reaching 100% on the first charge cycle
The BladderScan's charge IC applies a conservative current ceiling when it detects a new or previously unrecognised cell. On the first charge, it holds the termination threshold lower than the OEM cell's calibrated limit. The display may stop at 90–95% and show a full indicator despite the cell not being at true capacity. Running one complete charge-to-discharge cycle recalibrates the charge IC and allows subsequent charges to reach the correct 12.6V termination point.
Device shuts off unexpectedly during a scan after battery swap
During the first several cycles, new Li-ion cells have not yet reached full electrolyte wetting across all layers, which causes momentary voltage sag under the BladderScan's transducer firing load. The BMS reads this sag as a low-voltage event and triggers a protective shutdown before the cell is truly depleted. This is not a fault in the replacement — it resolves after approximately 10 full charge-discharge cycles as the cell reaches stable internal resistance. Until then, confirm the battery is charged to 12.6V before beginning a clinical session.