Fujitsu Amilo Li3710 Replacement Battery 11.1V 4400mAh

Fujitsu Amilo Li3710 / Li3910 / Pi3560 — 11.1V Li-ion Replacement Battery (SQU-809-F01)

This is an 11.1V, 4400mAh (48.84Wh) Li-ion replacement battery for the Fujitsu Amilo Li3710, Amilo Li3910, and Amilo Pi3560 laptops. It cross-references OEM part numbers SQU-809-F01, SQU-808-F01, SQU-808-F02, and 3UR18650-2-T0182, among others. If your original battery no longer holds a practical charge, this cell uses the same voltage rail and connector as the factory unit.

• Amilo Li3710, Li3910, and Pi3560 compatibility: All three models share the same 11.1V three-cell architecture, connector pinout, and BMS handshake protocol — so one cell covers the full platform without modification.
• Bench tested on actual hardware: We ran this cell through charge, full-discharge, and BMS communication checks. The protection circuit responded correctly to over-voltage and over-discharge thresholds, and the BIOS recognised the battery without error flags on first connection.
• First-cycle calibration after install: After fitting this battery, run one full discharge to the hibernate cutoff point, then charge uninterrupted to 100%. This forces the fuel gauge IC to re-learn the new cell's actual capacity and clears the inaccurate health warning that appears in the BIOS after every cell swap.

Why the Amilo Li3710 shuts down at 20–30% charge remaining

The Amilo Li3710 pulls significant current when the CPU and display are both under full load. An aged or uncalibrated cell hits a voltage cliff — the open-circuit voltage looks acceptable, but under load it drops below the BMS cutoff threshold instantly. The laptop interprets this as a dead cell and triggers an immediate shutdown, even though the fuel gauge still shows charge remaining. After the first calibration cycle on a new cell, this symptom disappears because the gauge IC now knows the true usable voltage range of the replacement chemistry.

BIOS reporting battery health as "poor" or "unknown" after fitting a new cell

The Amilo BIOS reads health data from EEPROM registers that were written by the original factory cell during its first cycles. A new cell ships with default or blank EEPROM values, which the BIOS flags as degraded or unrecognised. This is not a fault with the replacement — it is stale EEPROM data from the old cell being compared against a blank register. Run one full discharge-to-hibernate followed by an uninterrupted full charge; by the second cycle the BIOS battery learn routine overwrites the old register values and the health warning clears.