Huawei Mate 9 HB396689ECW Replacement Battery 3.82V 4000mAh

Huawei Mate 9 — 3.82V Li-Polymer Replacement Battery (HB396689ECW)

This is a 3.82V, 4000mAh Li-Polymer replacement battery for the Huawei Mate 9 smartphone. It carries OEM part number HB396689ECW and fits the Mate 9, Ascend Mate 9, Mate 9 Dual SIM, MHA-TL00, and related variants. At 15.28Wh, it matches the original cell's rated capacity.

• Mate 9 series fit: The Mate 9 line — including Dual SIM and MHA-TL00 variants — shares the same battery bay dimensions, connector pinout, and BMS handshake protocol. One cell covers all of them. Swapping between variants does not affect fitment.
• Bench tested on actual hardware: We ran this cell through the Mate 9's charge IC and BMS. The BMS accepted the cell without fault flags, charge termination triggered correctly at 4.35V, and the fuel gauge IC registered the full 4000mAh rated capacity across a calibration cycle.
• First-cycle recalibration on the Mate 9: Disable Huawei's SuperCharge on the first use after installation. Run one full discharge-to-charge cycle at standard 5V/2A. This lets the fuel gauge IC map its coulomb counter against the new cell's discharge curve before high-current charging is applied to an uncalibrated cell.

Sudden shutdown at 20–30% on the Mate 9 after a cell swap

This is a voltage cliff issue, not a capacity fault. Under heavy modem or display load, the cell's output voltage drops faster than the fuel gauge IC predicts — the phone's protection circuit trips before the reported percentage reaches zero. It happens because the coulomb counter is still calibrated to the old, degraded cell's discharge curve. Run two full discharge-charge cycles at standard voltage, and the fuel gauge IC will re-anchor its model to the new cell's actual curve. After recalibration, the shutdown point should move to below 5%.

Huawei SuperCharge not activating after battery replacement

SuperCharge requires a BMS handshake before the charge IC ramps current above the standard 5V/2A profile. On the first cycle after a cell swap, the BMS may not complete that negotiation — the phone charges slowly but shows no error. This is normal behaviour on the first cycle. Fully discharge the phone to under 5%, charge to 100% at standard rate, then unplug and recharge — SuperCharge should negotiate correctly from the second cycle onward. If it still does not activate, check that the battery connector is fully seated, as a partial connection breaks the BMS data line.