About this replacement
Philips Xenium S369 — 3.8V Li-Polymer Replacement Battery (AB3000MWMT)
This is a 3.8V, 2900mAh Li-Polymer replacement battery for the Philips Xenium S369 smartphone. It matches the OEM part number AB3000MWMT and fits the original battery bay without modification. Swap it when the factory cell can no longer hold charge through a normal day of use.
- Xenium S369 fitment: The S369 uses a slim 3.35mm Li-Polymer cell with a specific connector orientation and BMS handshake tied to the phone's charge IC. This cell matches that connector pinout and voltage rail so the charge IC recognises it correctly on first insertion.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on the S369 platform. The BMS reported state-of-charge within normal range, and the charge IC accepted standard charging current without throwing an error flag.
- Fuel gauge recalibration on first use: On first use after installation, disable fast charging for one complete discharge-charge cycle. This lets the fuel gauge IC map the new cell's discharge curve before high-current charging pushes current into an uncalibrated state.
Sudden shutdown at 20–30% on the Xenium S369
This is a voltage cliff failure. As a Li-Polymer cell ages, its internal resistance rises. Under load from the modem radio or screen, the cell voltage drops sharply — faster than the fuel gauge IC can track. The phone hits the hardware undervoltage cutoff before the displayed percentage reaches zero. A fresh cell with lower internal resistance holds voltage under the same load, so the cutoff no longer triggers early.
Phone won't power on after sitting in storage with a flat battery
If the original cell self-discharged below approximately 2.5V per cell during storage, the BMS enters a lockout state to prevent charging a critically depleted cell at full current. The phone appears completely dead and won't respond to the charger. Connect to a 5V USB source and leave it for 15–20 minutes without pressing the power button — the charge IC trickle-charges the cell out of lockout before handing off to normal charge current. Once the percentage appears on screen, normal charging resumes.