About this replacement
Asus Eee PC 901 / 1000 Series — 7.4V Li-ion Replacement Battery (AL23-901)
This is a 7.4V, 6600mAh (48.84Wh) Li-ion battery for the Asus Eee PC 901, 904, 904HD, and 1000 series netbooks. It replaces OEM part numbers AL23-901, AL24-1000, AP23-901, and 870AAQ159571. If your original cell holds no charge or the system won't run off battery at all, this is the direct cell swap.
- Eee PC 901 / 904 / 1000 platform fit: These models share the same 7.4V two-cell Li-ion architecture, identical connector pinout, and compatible BMS handshake protocol — which is why one cell covers all of them. Swapping between any of these models uses the same physical latch and charge circuit.
- Bench tested on actual hardware: We cycled this cell on an Eee PC 901 unit and confirmed the BMS communicates correctly with the BIOS — charge current ramps normally, the cell reports capacity data, and no error flags tripped at any point during the charge-discharge cycle.
- First-cycle calibration on the Eee PC: After installing, run one full discharge down to hibernate-cutoff, then charge uninterrupted to 100%. This resets the BIOS battery learn cycle and clears the inaccurate health warning that typically appears after every cell swap on these netbooks.
BIOS reporting battery health as poor after swapping cells on the Eee PC 901
The Eee PC BIOS reads health data from EEPROM registers built into the battery's BMS, not from live voltage alone. When a new cell arrives with factory-default EEPROM values, the BIOS compares them against calibration data from the old cell and flags a mismatch as poor health. This is not a defective cell — it's a calibration state. Run one full discharge-to-hibernate then a full uninterrupted charge, and the BIOS learn cycle overwrites the stale reference data with accurate figures from the new cell.
Eee PC shutting down at 20–30% battery shown on screen
The fuel gauge IC inside the battery calculates remaining charge based on a voltage-to-capacity curve calibrated to the previous cell's chemistry. After a cell swap, that curve is misaligned — the gauge reads 25% while the actual cell voltage has already hit the low-voltage cutoff. Under combined CPU and display load, voltage drops faster than the gauge tracks, and the BMS cuts power before the OS can write a hibernate file. Run two full discharge-to-charge cycles to force the fuel gauge IC to recalibrate against the new cell. After two cycles, the shutoff should align with the display — typically below 5% at around 6.8V under load.