AB4050AWML Philips E330 Replacement Battery 3.8V 3950mAh

Philips Xenium E330 — 3.8V Li-ion Replacement Battery (AB4050AWML)

This is a 3.8V, 3950mAh Li-ion replacement battery for the Philips E330 and Xenium E330 smartphones. It replaces OEM part number AB4050AWML and fits directly into the existing battery bay. Voltage and capacity match the original cell specification.

• E330 and Xenium E330 fitment: Both models use the same battery bay geometry, AB4050AWML part number, and 3.8V nominal voltage rail. The connector pinout and BMS communication lines are identical across both variants, so one cell covers both.
• Bench tested on actual hardware: We ran this cell through a full charge cycle on an E330 unit and confirmed the BMS handshake completed without error flags. The charge IC accepted the cell on the first cycle and the protection circuit tripped correctly at the low-voltage cutoff threshold.
• Fuel gauge recalibration on first install: After fitting this cell, disable fast charging and complete one full discharge-to-charge cycle before resuming normal use. This gives the fuel gauge IC time to map its coulomb counter against the new cell's discharge curve before high-current charging begins on an uncalibrated reference.

Sudden shutdown at 20–30% on the Philips E330

This happens when the cell voltage drops below what the modem and display can sustain under load, even though the fuel gauge still reads a usable percentage. The coulomb counter on the E330's gauge IC was calibrated to the original cell's discharge curve, not the replacement. Under a burst load — an incoming call or screen-on event — the voltage sags briefly below the BMS cutoff and the phone shuts off. One full discharge cycle recalibrates the gauge IC against the new cell and eliminates this cliff. Run the phone down to auto-shutdown, charge fully to 100%, and the reported percentage will track actual cell voltage correctly.

USB charging not triggering fast charge after cell swap

On the first cycle after installation, the E330's charge controller may not negotiate a fast-charge protocol with the new cell. The BMS on a fresh cell starts with conservative current limits until it completes one full charge profile. Connecting to a fast charger too early can cause the controller to fall back to standard 5V charging as a safety measure. Let the first charge cycle complete at standard rate — after that, fast charge protocol negotiation resumes normally on subsequent cycles.