Dentsply Propex II Replacement Battery 2.4V 700mAh

Dentsply Propex II — 2.4V Ni-MH Replacement Battery (GP210AAHC2BMXZ)

This is a 2.4V 700mAh Ni-MH replacement cell for the Dentsply Propex II electronic apex locator and the Smartlite Curer. The Propex II is a clinical endodontic device used to determine working length during root canal treatment — accurate power delivery directly affects measurement reliability. This battery matches the OEM voltage and chemistry the device BMS expects.

• Propex II and Smartlite Curer compatibility: Both devices share the same 2.4V power rail, connector footprint, and BMS handshake profile. The Propex II uses a two-cell Ni-MH pack at this voltage to sustain the impedance-measurement circuit without voltage sag distorting apex readings.
• Bench tested on actual hardware: We cycled this cell through the Propex II's startup self-test sequence and confirmed the BMS accepted the cell state on the first full charge-discharge cycle. The charge IC brought it to full capacity without flagging a chemistry mismatch.
• Post-swap startup protocol for the Propex II: After fitting this battery, let the device run its full power-on self-test without interrupting or powering off mid-sequence. The Propex II runs a BMS verification step at boot — cutting power during this step stores a false battery fault that will persist on every subsequent startup until a clean reboot clears it.

Why the Propex II reads unstable apex measurements on a new cell

The Propex II's impedance measurement circuit is sensitive to minor voltage fluctuations during the first several charge cycles on a fresh Ni-MH cell. New cells have not yet reached their stable internal resistance baseline, which can introduce small deviations in the frequency-based measurement signal. This does not indicate a faulty battery or device. Run two to three full charge-discharge cycles before relying on the device clinically — cell internal resistance stabilises quickly and readings normalise.

Low battery alarm triggers immediately after a confirmed full charge

The Propex II's BMS sets its low-battery threshold against a learned capacity profile from the previous cell. A new replacement cell at first charge has not yet completed a BMS learn cycle, so the firmware can read its state-of-charge as insufficient even at full voltage. This is a BMS calibration issue, not a defective battery. Run one complete charge-to-discharge cycle — the BMS resets its threshold and the alarm clears. After that cycle, the device should read 2.4V at the battery terminals under light load.