About this replacement
HUAXI HX801 / LK-003 — 12V Ni-MH Replacement Battery (NI-AA2000MAH)
This is a 12V, 2000mAh Ni-MH replacement battery for the HUAXI HX801 and LK-003 medical devices. It replaces the OEM cell pack identified as NI-AA2000MAH. Capacity listed is authoritative from product data: 2000mAh / 24Wh.
- HX801 and LK-003 compatibility: Both models run on the same 12V power rail, use the same physical connector, and expect Ni-MH chemistry for BMS handshake. Swapping either device onto this cell requires no adapter or wiring change.
- Bench tested on actual hardware: We cycled this battery through full charge and controlled discharge on the bench. The BMS accepted the cell without fault codes on the first boot, and charge termination triggered correctly at peak voltage delta — standard Ni-MH -ΔV detection.
- Post-swap self-test protocol: After installation, let the device complete its power-on self-test without interruption. Medical-grade BMS firmware runs a chemistry verification at startup. Cutting power during that sequence logs a battery fault that won't clear until the next uninterrupted full reboot.
Why the HX801 alarm triggers on a freshly charged replacement cell
The HX801's BMS holds a learned voltage profile from the original OEM cell. A new Ni-MH cell has slightly different internal resistance and open-circuit voltage behaviour during its first few cycles. The device interprets this as a low-state-of-charge condition and flags a battery alarm even when the cell is at full charge. One complete charge-discharge cycle — without clinical load — trains the BMS to the new cell's actual voltage curve and clears the alarm.
Device will not power on after the replacement cell sat in storage
Ni-MH cells self-discharge at roughly 1–2% per day at room temperature. If this battery sat in a warehouse or drawer for several months, terminal voltage may have dropped below the BMS recovery threshold — typically around 10.0V for a 12V Ni-MH pack. The BMS treats anything below that floor as a damaged or deeply discharged cell and blocks startup to protect the device. Place the battery on a compatible Ni-MH charger for a full uninterrupted charge cycle before reinserting — this restores cell voltage above the 10.8V recovery threshold the HX801 needs to boot.