Acer P300 Replacement Battery 3.7V 900mAh S11B03B

Acer neoTouch P300 — 3.7V Li-ion Replacement Battery (S11B03B)

This is a 3.7V, 900mAh Li-ion battery for the Acer P300 and neoTouch P300 smartphones. It replaces OEM part numbers S11B03B and BT.0010X.002. Swap it in when the original cell can no longer hold charge through a normal day of calls, messaging, and screen-on time.

• P300 and neoTouch P300 fit: Both models run the same 3.7V single-cell architecture with an identical connector and BMS handshake, so one cell covers both variants without modification.
• Bench tested on actual hardware: We cycled this cell on a P300 unit, confirmed the BMS accepted the new cell without error flags, and verified the charge IC ramped to full charge current without thermal cutoff.
• Fuel gauge recalibration after swap: On first use after installation, disable fast charging and run one full discharge-charge cycle. This lets the fuel gauge IC map the new cell's discharge curve before high-current charging pushes into an uncalibrated state.

Sudden shutdown at 20–30% on the P300 after a cell swap

A new cell has a slightly different voltage-versus-capacity curve than the degraded cell the fuel gauge IC was calibrated to. When the modem fires a burst transmission or the screen peaks in brightness, current draw spikes. If the fuel gauge IC still expects the old cell's curve, it can allow discharge past the point where the new cell can sustain the minimum voltage rail — the phone cuts out even though the reported percentage looks safe. One full discharge-charge cycle with the screen on and mobile data active forces the coulomb counter to re-anchor to the new cell. After that cycle, shutdowns at 20–30% typically stop.

P300 reporting wrong battery percentage after replacement

The fuel gauge IC on the P300 stores a learned discharge model from the previous cell. A fresh 900mAh cell has different internal resistance and a steeper end-of-discharge curve, so the IC's stored model no longer matches reality. The result is percentage readings that jump erratically or plateau at values like 50% before dropping fast. Drain the battery fully until the phone powers off, then charge uninterrupted to 100% — this gives the coulomb counter a full reference sweep and corrects the reported percentage within one to two cycles.