Huawei Band 2 Pro Compatible Battery HBL6A 3.7V 1100mAh

Huawei C2600 / C2800 Series — 3.7V Li-ion Replacement Battery (HBL6A)

This 3.7V, 1100mAh Li-ion cell replaces the original battery in Huawei C2600, C2606, C2800, C2808, and related Band 2 Pro smartwatch variants. It matches the OEM voltage and physical footprint, including the 54.70 × 34.33 × 7.10mm form factor. Capacity is rated at 4.07Wh — drawn from the product specification, not extrapolated.

• C2600 / C2800 platform fit: These models share the same connector layout, BMS handshake protocol, and voltage rail. The HBL6A cell is recognized by the fuel gauge IC across all listed variants without modification.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on a C2600 unit. The BMS accepted the cell without fault flags, and the fuel gauge IC pulled accurate state-of-charge data after one full cycle.
• Fuel gauge recalibration after install: On first use, disable fast charging if the option is available and run one full discharge-to-charge cycle. This lets the fuel gauge IC map the new cell's discharge curve before it locks in percentage reporting — skipping this step often triggers erratic percentage jumps in the first few days.

Sudden shutdown at 20–30% on the C2600 after a cell swap

This happens because the fuel gauge IC is still calibrated to the old cell's discharge curve. The new cell hits a voltage cliff — a point where internal voltage drops sharply under sensor or display load — before the gauge reaches 0%. The device interprets this as a valid shutdown threshold even though the gauge still shows charge remaining. One full discharge cycle, taken down to the watch's automatic power-off point and then charged to 100%, resets the coulomb counter against the new cell chemistry.

Device not powering on after the replacement cell sat in storage

Li-ion cells stored below approximately 2.5V trigger a BMS lockout — the protection circuit opens and blocks current flow to prevent damage from deep discharge. Plugging directly into the charger may appear to do nothing for the first several minutes. Apply a slow charge at the lowest available current source; most BMS circuits will re-initialize once the cell climbs back above 2.8V and the charger should then show a normal charging state.