About this replacement
Acer Aspire 5601AWLMi Series — 11.1V Li-ion Replacement Battery (3UR18650Y-2-QC236)
This is an 11.1V, 4400mAh (48.84Wh) Li-ion replacement battery for the Acer Aspire 5601AWLMi and related Aspire 7000 series notebooks. It slots into the original bay and connects via the same multi-pin connector used across this platform. Use the OEM part number 3UR18650Y-2-QC236 to confirm your unit is a match before ordering.
- Aspire 5601AWLMi and 7000 series fit: These models share the same 11.1V three-cell architecture, connector pinout, and BMS handshake protocol. Acer sourced one battery pack across all these SKUs at the factory level, so the same replacement cell works across the full range.
- Bench tested on actual hardware: We ran this cell through full charge and discharge cycles on the Aspire platform. The BMS negotiated correctly with the BIOS, charge current tapered normally at the top of the cycle, and no protection trips occurred during the load phase.
- BIOS learn cycle after swap: After fitting this cell, run the laptop down to hibernate cutoff on battery power, then charge uninterrupted to 100%. This resets the BIOS battery learn cycle and clears the inaccurate health warning that typically appears after any cell replacement on this platform.
Why the Aspire 7000 series BIOS flags a new cell as poor health immediately after swap
The Aspire BIOS reads health data from EEPROM stored on the battery pack, not from a live chemistry test. When a new cell arrives, that EEPROM contains factory-default values that do not match the BIOS's learned profile from the old pack. The firmware interprets this mismatch as a degraded or unknown battery. Running one full discharge-to-hibernate followed by an uninterrupted full charge forces the BIOS to overwrite its stored profile with data from the new cell, resolving the warning.
Laptop shuts down at 20–30% charge shown on the gauge
This is a voltage cliff failure — under combined CPU and display load, the cell voltage drops faster than the fuel gauge IC predicts, triggering a hard shutdown before the displayed percentage reaches zero. It happens when the fuel gauge IC has not yet calibrated against the new cell's actual discharge curve. The fix is two to three full calibration cycles: discharge to hibernate cutoff under normal use, then charge fully to 100% each time. After the third cycle, the gauge IC has enough data to map the real voltage curve and the shutdowns stop.