Spacelabs 90367 Patient Monitor Replacement Battery 12V 2450mAh

Spacelabs 90367 / Ultraview Series — 12V Ni-MH Replacement Battery (146-0055-00)

This is a 12V 2450mAh Ni-MH replacement battery for the Spacelabs 90367 patient monitor and compatible Ultraview series devices. It fits the 90367, 91369, Ultraview 1050, and Ultraview 2400 portable vital signs monitors used in hospital and clinical environments. Voltage and capacity match OEM spec at 12V and 2450mAh (29.4Wh).

• 90367, 91369, and Ultraview platform compatibility: These models share the same 12V battery rail, physical form factor, and BMS handshake protocol. A single replacement cell covers the full platform without connector or firmware conflicts.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on a Spacelabs-compatible test rig. The BMS completed recognition without fault codes, and the charge circuit accepted the cell without triggering a false low-battery alarm.
• Power-on self-test protocol: After installing this battery, allow the monitor to complete its full startup sequence without interruption. The 90367 runs a BMS verification check at boot — cutting power during this window writes a battery fault flag that persists until the next clean reboot cycle.

Why the 90367 reports low battery immediately after a confirmed full charge

The Spacelabs 90367 BMS stores a learned capacity profile from the previous cell. When a new Ni-MH cell is installed, the BMS compares the first discharge curve against that stored profile — if the curve doesn't match, it flags low battery regardless of actual charge state. This is not a fault in the replacement cell. Run one complete charge-discharge cycle on the device before clinical deployment, and the BMS will recalibrate its threshold to the new cell's actual chemistry and capacity curve.

Monitor will not power on after battery has been in storage

Ni-MH cells self-discharge during storage — if the cell drops below approximately 10.0V, the 90367's BMS enters deep-discharge protection and blocks power-on entirely. The fix is to apply a slow trickle charge externally or place the cell in the device and leave it connected to mains for at least two hours before attempting startup. Once the cell recovers above the BMS recovery threshold, the device will boot normally. Do not attempt repeated power-on presses before the cell has had time to recover — this does not bypass the protection circuit.