Huawei Honor Note 8 HB3872A5ECW Replacement Battery 3.82V 4500mAh

Huawei Honor Note 8 — 3.82V Li-Polymer Replacement Battery (HB3872A5ECW)

The HB3872A5ECW is a 3.82V, 4500mAh Li-Polymer cell that fits the Huawei Honor Note 8, Honor Note 8 Premium, Honor Note 8 Standard Edition, and EDI-AL10 variants. It replaces the original cell when the phone shuts down unexpectedly, no longer holds a charge, or swells. Capacity is 17.19Wh, matching the original specification.

• EDI-AL10 and Note 8 variant coverage: All listed variants — Standard Edition, Premium, and EDI-AL10 — share the same battery bay dimensions (103.40 × 71.10 × 3.50 mm), connector pinout, and BMS handshake protocol. One cell fits the full range without modification.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the EDI-AL10 platform. The BMS accepted charge current normally, protection circuits triggered correctly at low-voltage cutoff, and the fuel gauge IC tracked state-of-charge without error flags after a full calibration cycle.
• First-cycle fast charge handling: On first use after installation, disable Huawei's SuperCharge protocol for one complete discharge-charge cycle. This gives the fuel gauge IC time to map the new cell's discharge curve before high-current charging pushes current into an uncalibrated cell — preventing premature percentage drops mid-session.

Sudden shutdown at 20–30% on the Note 8 after a cell swap

The Honor Note 8's large 6.6-inch display and modem draw significant current spikes. A new cell's internal impedance differs slightly from the aged cell the fuel gauge IC was calibrated against. Under load, the voltage drops faster than the coulomb counter predicts, triggering a low-voltage protection cutoff before the displayed percentage reaches zero. One full discharge-to-3.50V and slow recharge cycle recalibrates the IC and eliminates the false cutoff.

SuperCharge not activating on the first charge after replacement

Huawei's SuperCharge handshake requires the charge IC to confirm cell voltage is within a valid acceptance window before switching to high-current mode. On a new cell coming out of storage, resting voltage may sit below the threshold the charger expects. Plug in via the stock cable, allow a standard 5V trickle charge to bring the cell above 3.65V, then unplug and reconnect — the SuperCharge handshake will complete on the second connection.