HB526489ECW Huawei Y6p Replacement Battery 3.85V 4650mAh

Huawei Y6p / MED-LX9 — 3.85V Li-Polymer Replacement Battery (HB526489ECW)

This is a 3.85V, 4650mAh (17.9Wh) lithium-polymer replacement battery for the Huawei Y6p smartphone, including variants MED-LX9, MED-L29, and MED-LX9N. It replaces OEM part HB526489ECW directly. Fit this cell when the original no longer holds a usable charge or has swollen and needs to come out.

• Y6p variant coverage: The MED-LX9, MED-L29, and MED-LX9N all share the same battery bay geometry, connector pinout, and BMS handshake protocol — one cell fits the full production run of this model family.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on a Y6p unit, verified the BMS accepted the charge IC handshake without fault flags, and confirmed the coulomb counter initialised correctly across the full voltage range.
• Fuel gauge recalibration on first use: After installation, disable fast charging and run one complete discharge down to auto-shutdown, then charge to 100% uninterrupted. This gives the fuel gauge IC a clean discharge curve to map against the new cell before high-current charging begins.

Sudden shutdown at 20–30% on the Huawei Y6p after a cell swap

This happens because the fuel gauge IC is still running a discharge curve calibrated to the old, degraded cell. When the new cell's open-circuit voltage drops into a range the IC misreads as critical, it triggers an emergency shutdown — even though actual remaining capacity is higher. The fix is one full uninterrupted discharge-to-shutdown followed by a complete charge cycle with fast charging disabled. After that cycle, the coulomb counter recalibrates and the percentage readings stabilise. If shutdowns continue past two full cycles, check that the battery connector is fully seated — a partial connection causes voltage drop under modem load.

USB fast charging not activating on the first cycle after replacement

On first plug-in after a cell swap, the Huawei charge IC runs a pre-charge trickle phase to verify the new cell's impedance before negotiating fast charge. If the charger handshake times out during this phase, the phone falls back to standard 5V charging for that session. This is normal behaviour on the first cycle — fast charge typically activates from the second full session onward once the IC has logged a baseline cell profile. Use the original Huawei charger for the first two cycles; third-party chargers can interrupt the proprietary protocol negotiation and extend the delay.