About this replacement
HUAXI HX-903A — 11.1V Li-ion Replacement Battery
This is a 11.1V, 3000mAh (33.3Wh) lithium-ion replacement battery for the HUAXI HX-903A portable medical device. It restores power to depleted or failed original battery packs in clinical and patient care settings. Dimensions are 66.20 × 50.00 × 23.20mm — confirm these against your existing pack before installation.
- HX-903A fit: This cell matches the HX-903A's 11.1V three-cell configuration and connector footprint. The BMS expects a nominal 11.1V rail at startup — deviation outside that range triggers an immediate fault on boot.
- Bench tested on actual hardware: We cycled this battery through charge and discharge on medical-grade test equipment. The BMS responded correctly at all three protection thresholds: overcharge, over-discharge, and short-circuit cutoff.
- Post-installation self-test: After fitting this battery, let the HX-903A complete its full power-on self-test without interruption. Medical devices run BMS verification at startup — cutting power mid-sequence registers a false battery fault that persists until the next clean reboot.
HX-903A not completing boot sequence after battery swap
The HX-903A runs a BMS handshake during boot that checks cell voltage against stored calibration values. A new cell fresh from packaging may sit at a resting voltage slightly outside the device's expected window — typically below 11.1V nominal after storage. This can cause the boot sequence to stall or abort before the home screen loads. Charge the battery to full before the first installation, then power on the device and allow the self-test to finish uninterrupted.
Charge indicator not reaching 100% on first charge
On the first charge cycle, the HX-903A's charge IC applies a conservative current limit to a new cell it hasn't profiled yet. The indicator may plateau at 90–95% and stop climbing. This is the charge controller holding back, not a cell fault. Run one complete charge-discharge-recharge cycle and the controller recalibrates — the indicator will reach 100% on subsequent charges.