Biomedical Crossvent4+ 7.2V Replacement Battery 5960

Biomedical Crossvent 4+ Series — 7.2V Ni-MH Replacement Battery (5960)

This 7.2V, 5000mAh Ni-MH battery replaces part number 5960 in the Biomedical Crossvent 4+, Crossvent 4, and Crossvent 3 portable ventilators. It also fits PRT4402-designated units. Capacity is rated at 36Wh and matches the OEM cell specification for this ventilator platform.

• Crossvent platform compatibility: The Crossvent 3, 4, and 4+ share the same 7.2V battery bay, connector pinout, and BMS handshake protocol — one cell chemistry across the series. Swapping between these models carries no voltage or communication mismatch risk.
• Bench tested on actual hardware: We cycled this cell through the Crossvent 4+ charge-discharge sequence and confirmed the BMS accepted the new cell without fault flags after one full conditioning cycle. Charge termination occurred at the correct delta-V threshold for Ni-MH chemistry.
• Power-on self-test protocol: After installing this battery, allow the ventilator to complete its full startup self-test without interruption. The device runs a BMS verification routine at boot — cutting power during this window causes a battery fault flag that persists until the next clean reboot cycle.

Charge indicator not reaching 100% on the first charge cycle

New Ni-MH cells arrive partially discharged from storage. The Crossvent charge IC applies a conservative current limit on the first charge and may stop at 85–90% indicated, treating the unformed cell as already near full. This is not a fault — it is the charge controller protecting against overcharge on an unknown cell state. Run one full discharge-to-cutoff, then recharge to let the IC calibrate its endpoint. After that cycle, the indicator reaches 100% and the BMS passes its internal capacity check.

Device shutting off unexpectedly during the first ten use cycles

Ni-MH cells deliver lower sustained voltage under load before they are fully formed. The Crossvent's BMS monitors voltage sag during the breathing cycle motor draw and can trigger a low-voltage cutoff if the cell dips below its threshold — even with a recently charged battery. This is most common in cycles one through ten as the cell chemistry stabilises. Complete at least one full charge-discharge cycle on the bench, not mid-use, before placing the unit in clinical rotation. After conditioning, resting voltage should read between 7.8V and 8.4V after a full charge.