Asus M10 Replacement Battery SBP-23 3.7V 1200mAh

Asus M10 / M10E / A10 / T20 — 3.7V Li-ion Replacement Battery (SBP-23)

This is a 3.7V, 1200mAh Li-ion replacement cell for the Asus M10, M10E, A10, and T20 smartphones. It fits the original battery bay and connects via the same multi-pin connector. Use it when the stock cell no longer holds a charge or the phone shuts off unexpectedly.

• M10 / M10E / A10 / T20 fit group: These four models share the same PCB footprint, connector pinout, and BMS communication protocol — one cell covers the full set without modification.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on M10 hardware. The BMS accepted the cell on first connection, charge current ramped correctly, and the protection circuit tripped at the expected cutoff voltage under load.
• Fuel gauge recalibration on first use: After installation, run one full discharge down to auto-shutoff and then charge uninterrupted to 100% before enabling fast charge. This gives the fuel gauge IC one complete cycle to map the new cell's discharge curve — skipping it leads to erratic percentage readings in the first few days.

Sudden shutdown at 20–30% on the new cell

A fresh cell has a slightly different voltage curve than the worn cell the fuel gauge IC was calibrated to. Under a burst load — screen at full brightness, LTE data, or GPS active simultaneously — the phone's fuel gauge misreads available capacity and the system cuts power before the cell is actually empty. This is a calibration gap, not a faulty battery. One full discharge-to-shutoff followed by a full uninterrupted charge resets the coulomb counter. After that cycle, shutoffs below 15% drop significantly.

Phone will not power on after the battery sat discharged in storage

If the cell voltage dropped below approximately 2.5V during storage, the BMS enters lockout mode to prevent charging a deeply discharged lithium cell. The phone shows no sign of life even when plugged in. Connect the phone to the original Asus charger — not a USB hub or laptop port — and leave it for 20–30 minutes without pressing the power button. The charger delivers a trickle current that brings the cell above the BMS recovery threshold, typically around 2.9V, at which point normal charging resumes.