About this replacement
Huawei Honor V9 / Honor 8 Pro — 3.82V Li-Polymer Replacement Battery (HB376994ECW)
This is a 3.82V, 4000mAh (15.28Wh) Li-Polymer battery for the Huawei Honor V9, Honor 8 Pro, and compatible variants including DUK-AL20 and DUK-TL30. It replaces the original HB376994ECW cell and restores power to the display, Kirin processor, and LTE modem. Install it when the original cell degrades, swells, or can no longer hold a consistent charge through a full day.
- Honor V9 and DUK-series compatibility: The DUK-AL20, DUK-TL30, and Honor 8 Pro share the same battery bay dimensions, connector pinout, and charge IC interface as the standard Honor V9. All run the same HB376994ECW cell spec — 92.40 × 68.70 × 3.50mm with matched BMS communication lines.
- Bench tested on actual hardware: We cycled this cell through full charge and discharge on an Honor V9 unit. The BMS accepted the cell handshake without rejection, charge IC stepped through trickle, CC, and CV phases cleanly, and protection cutoffs triggered at expected thresholds.
- Fuel gauge recalibration on first use: After installation, disable Huawei's SuperCharge for the first complete discharge-charge cycle. The fuel gauge IC calibrates its coulomb counter against the new cell's discharge curve. Running SuperCharge before that first full cycle pushes high current into an uncalibrated cell and produces inaccurate percentage readings for weeks.
Sudden shutdown at 20–30% on the Honor V9 after a cell swap
The Honor V9 shuts down before the percentage hits zero because the fuel gauge IC is still reading the old cell's voltage-to-capacity curve. The new cell's internal resistance profile is different, and under modem or display load, voltage sags past the hardware cutoff point even when the reported percentage looks safe. This is not a faulty battery — it is a calibration gap. Run two full discharge-charge cycles without SuperCharge enabled, and the coulomb counter will remap to the new cell's actual voltage floor.
SuperCharge not activating after battery replacement
Huawei's SuperCharge protocol requires a handshake between the charge IC and the battery BMS on the first connection. If the BMS has not yet been initialised — common when a replacement cell ships in partial-discharge storage state — the charge IC falls back to standard 5V charging and SuperCharge never engages. Connect the phone to a SuperCharge adapter and let it charge uninterrupted to 100% without rebooting mid-cycle. On most units, the protocol handshake completes by the second charge session and the fast charge indicator returns.