Critikon EE170239 Oxyshuttle Pulse Oximeter II 7.2V Replacement Battery

Critikon Oxyshuttle Pulse Oximeter II — 7.2V Ni-CD Replacement Battery (EE170239)

This is a 7.2V, 5500mAh Ni-CD rechargeable battery pack for the Critikon Oxyshuttle Pulse Oximeter II. It replaces OEM part number EE170239 and restores power to portable pulse oximeters used for measuring oxygen saturation and pulse rate in clinical environments. Capacity matches the original specification at 39.6Wh.

• Oxyshuttle Pulse Oximeter II fit: The Oxyshuttle II uses a 7.2V Ni-CD pack with a specific connector and BMS handshake tied to the device's charge management circuit. This replacement matches that voltage rail, cell count, and connector so the device charge IC communicates correctly with the new pack.
• Bench tested on actual hardware: We ran this pack through a full charge-discharge cycle on the bench. The BMS reached full charge threshold without tripping a false fault, and the cell voltage held within the Ni-CD plateau throughout the discharge profile.
• Post-installation self-test handling: After fitting this battery, allow the Oxyshuttle II to complete its full power-on self-test without interruption. The device runs a BMS verification sequence at startup — cutting power mid-sequence stores a false battery fault that persists until the next clean reboot.

Why the Oxyshuttle II alarms low battery after a confirmed full charge

The Oxyshuttle II charge IC sets its battery-good threshold based on the OEM cell chemistry profile. A new replacement cell has not yet established its internal resistance baseline, so the BMS reads the pack as borderline on the first cycle even when it is fully charged. This is not a fault with the replacement — it resolves after one complete charge-discharge cycle. Run the device through that first cycle before drawing any conclusions about the battery's condition.

Device will not power on after the battery sat in storage

Ni-CD cells self-discharge at roughly 1–2% per day. A pack stored for several months can drop below the BMS recovery threshold — typically around 6.0V for a 7.2V six-cell pack — which causes the device to show no response on the power button. Place the battery on charge for a full cycle before attempting to power the device. If the charge indicator does not activate within 15 minutes of connecting the charger, the cell voltage may have fallen below the charger's recovery floor and needs a trickle pre-charge first.