Servox Speech 7.2V Replacement Battery 19632 230mAh

Servox Speech / Digital XL Speech — 7.2V Ni-MH Replacement Battery (19632)

This is a 7.2V, 230mAh Ni-MH replacement battery for the Servox Speech and Digital XL Speech electrolarynx devices. It fits the OEM part number 19632 and the D45N7 cell configuration. The electrolarynx is a speech restoration device used by laryngectomy patients, so keeping this battery functional is not optional — it is the voice.

• Speech and Digital XL Speech compatibility: Both models share the same 7.2V Ni-MH cell stack, connector pinout, and BMS handshake protocol. The same battery services either unit without modification.
• Bench tested on actual hardware: We cycled this cell through the Servox charge-discharge sequence and confirmed the BMS accepted the cell, completed the verification pass, and held voltage within spec across the full discharge curve.
• Electrolarynx power-on self-test: After installing this battery, allow the device to complete its full power-on self-test without interruption. The Servox BMS runs a chemistry verification at startup. Interrupting that sequence triggers a false battery fault that persists until the next clean reboot.

Low battery alarm on the Servox Speech immediately after a confirmed full charge

The Servox BMS compares incoming cell voltage against an OEM reference threshold calibrated for a seasoned Ni-MH cell. A new replacement cell often sits just below that threshold on the first cycle, even after a complete charge. The device reads it as low and triggers the alarm. This is not a fault with the battery — it is the BMS learning the new cell's resting voltage profile. Run one full charge-discharge cycle before clinical use and the alarm clears.

Servox Speech will not power on after the battery has been in storage

Ni-MH cells self-discharge at roughly 1–2% per day under storage conditions. A cell that has sat for several weeks can drop below the BMS recovery threshold — typically around 5.4V for a 7.2V pack — and the device refuses to boot. Place the battery on charge immediately and leave it for a full uninterrupted charge cycle before attempting to power on the device. If the charger does not initiate, the cell may need a trickle pre-charge; confirm charger output at the contacts and check for at least 0.5V across the battery terminals before proceeding.