About this replacement
Huawei Nova 8 SE — 3.87V Li-Polymer Replacement Battery (HB446589EFW)
This 3.87V, 4100mAh Li-Polymer battery replaces part number HB446589EFW in the Huawei Nova 8 SE and compatible models including the NZONE S7 Pro, SP200, and Nova 10Z. It matches the original cell dimensions at 86.70 × 61.80 × 4.10mm, so it seats correctly in the battery bay without modification. Capacity is rated at 15.87Wh — identical to factory spec.
- Nova 8 SE / NZONE S7 Pro / Nova 10Z platform fit: These models share the HB446589EFW footprint because they run on the same battery bay geometry and BMS connector pinout. The same 3.87V nominal rail powers the Kirin SoC, display panel, and modem across the platform without a firmware difference at the charge IC level.
- Bench tested on actual hardware: We ran this cell through a full charge and discharge cycle on a Nova 8 SE unit. The BMS accepted charge handshake on first insertion, the charge IC held the correct 4.48V termination voltage, and no over-temperature flags triggered at the battery contact.
- First-cycle fast charge protocol: On first use after installation, disable fast charging for one complete discharge-charge cycle. This lets the fuel gauge IC recalibrate against the new cell's discharge curve before high-current charging pushes current into an uncalibrated cell — preventing early coulomb counter drift.
Why the Nova 8 SE reports wrong battery percentage after a cell swap
The fuel gauge IC stores a learned discharge curve from the original cell. When a new cell goes in, the IC still references that old curve — so the percentage shown on screen no longer maps accurately to actual charge state. This shows up as the phone reading 40% but shutting off, or jumping from 60% to 20% without warning. One full discharge down to automatic shutdown followed by an uninterrupted charge to 100% forces the coulomb counter to re-anchor to the new cell's actual capacity. After that single calibration cycle, percentage reporting stabilises.
Sudden shutdown at 20–30% on the replacement cell
This is a voltage cliff, not a capacity fault. Under peak modem load or display brightness, the cell voltage sags below the BMS cutoff threshold — typically around 3.2V — even though the fuel gauge still shows charge remaining. The old cell curve stored in the IC tells the phone there's usable capacity left, but the hardware shuts down to protect the cell. Run one full calibration cycle first: drain to zero, charge to 100% without interruption, standard charge only. If the shutdowns continue after calibration, check that the battery connector is fully seated — a partially engaged connector increases resistance and worsens voltage sag under load.