About this replacement
Huawei Watch GT3 Pro 46mm — 3.87V Li-Polymer Replacement Battery (HB572728EFW)
This 3.87V, 510mAh Li-Polymer cell is a direct replacement for the battery inside the Huawei Watch GT3 Pro 46mm. It fits the 46mm chassis specifically — not the 43mm variant. Voltage and connector match the original HB572728EFW specification.
- GT3 Pro 46mm platform fit: The 46mm and 43mm GT3 Pro models use different cell sizes and connector orientations. This cell is sized and wired for the 46mm board only. Fitting it to the smaller chassis will not work — the connector will not seat correctly.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the GT3 Pro 46mm platform. The BMS accepted the new cell without flagging a fault, and the fuel gauge IC responded correctly after a full charge cycle post-swap.
- Post-swap charge protocol for GT3 Pro 46mm: Place the watch on its magnetic charger immediately after fitting this cell and charge to 100% before first use. The fuel gauge IC on this platform loses its reference point when the original cell is disconnected. Without a full charge cycle from near-zero, the gauge cannot recalibrate — the watch will show inaccurate state-of-charge readings.
Heart rate sensor current draw on a freshly fitted cell
The GT3 Pro 46mm uses a multi-LED optical heart rate sensor that runs continuous sampling when wrist detection is active. On a new cell, the internal impedance is slightly higher than a settled cell, and the BMS may deliver current less efficiently during the first several charge-discharge cycles. This can make battery drain appear faster than expected in the first week after a swap. The behaviour normalises as the cell completes its initial cycles — no settings change is needed.
Watch not pairing with phone after battery replacement
Removing the battery cuts power to the BLE module and clears its active session state. When the watch restarts with the new cell, the phone's Huawei Health app may no longer recognise the device automatically. Open Huawei Health, navigate to the device management screen, remove the GT3 Pro entry, then re-add the watch as a new device. Re-pairing takes under two minutes and restores all sync functions. Do not attempt to pair until the watch has completed its first full charge to 100%.