About this replacement
Bionet BM3VET Next Monitor — 10.8V Li-ion Replacement Battery (BN190311)
This is a 10.8V, 3400mAh Li-ion replacement battery for the Bionet BM3VET Next Monitor and related BM-series veterinary vital signs monitors. It fits the BM3VET Next, BM3, BM3Vet, and BM5Vet platforms. Capacity matches the OEM specification at 36.72Wh — no derating.
- BM-series platform fit: The BM3, BM3Vet, BM5Vet, and BM3VET Next share the same 10.8V battery bay, connector pinout, and BMS communication protocol. One cell pack covers all four models without modification.
- Bench tested on actual hardware: We cycled this pack through charge and discharge on a BM3VET Next unit. The BMS handshake completed on first insertion, charge IC accepted the cell, and the protection circuit held within spec across both low-load standby and high-draw alarm-state simulation.
- Post-swap power-on sequence: After installing this battery, let the monitor complete its full power-on self-test without interruption. The BMS runs a verification routine at startup — cutting power mid-sequence triggers a false battery fault that persists until the next clean reboot.
BM3VET Next alarming low battery immediately after a confirmed full charge
This happens because the monitor's charge IC applies a conservative acceptance threshold calibrated to the OEM cell's internal resistance profile. A new replacement cell has slightly different impedance characteristics on arrival, and the BMS flags it as below threshold even when voltage reads correct. The fix is one complete charge-discharge cycle — discharge until the monitor powers off under normal load, then charge uninterrupted to full. After that cycle, the BMS recalibrates its threshold and the low-battery alarm clears. Confirm charge completion at 12.6V measured at the pack terminals before returning the unit to clinical use.
Monitor will not power on after battery was stored or left uninstalled
Li-ion cells self-discharge during storage. If the pack voltage drops below approximately 9V, the BMS trips into deep-discharge protection mode and blocks output entirely — the monitor shows no response at all, not even a low-battery indicator. Connect the monitor to mains power first and leave it on the charger for at least 60 minutes before attempting to power on. The charge IC will slowly recover the cell voltage above the BMS recovery threshold, typically around 10.0V, at which point normal startup resumes.