About this replacement
Acer Aspire S3-951 Series — 11.1V Li-Polymer Replacement Battery (AP11D3F)
This 11.1V, 3280mAh lithium-polymer battery replaces the original cell in the Acer Aspire S3 and Aspire S3-951 ultrabook lineup. It fits the slim 8.00mm profile of the S3 chassis and matches the OEM connector and BMS handshake for the AP11D3F and AP11D4F part numbers. Capacity is 36.41Wh — identical to the factory specification.
- Aspire S3 and S3-951 compatibility: The S3 series shares a single battery bay across the 13.3-inch ultrabook variants. All use the same 11.1V three-cell lithium-polymer configuration, the same flat ribbon connector, and the same BMS communication protocol — which is why one cell covers the full S3-951 range including the 2464G24iss and 64 additional sub-models.
- Bench tested on actual hardware: We ran this cell on an S3-951 unit and confirmed the BMS handshake completed on first boot. The BIOS accepted the battery as a known cell, charge initiation began within 90 seconds, and the protection circuit responded correctly to a controlled over-discharge test.
- Post-install learn cycle on the Aspire S3: After fitting, let the battery discharge fully until the laptop hibernates, then charge uninterrupted to 100% without using the machine. This triggers the S3's BIOS battery learn cycle, resets the fuel gauge IC against the new cell's actual capacity, and clears the false health warning that appears after every cell swap.
Why the Aspire S3 BIOS reports poor battery health after a cell swap
The Aspire S3 stores battery health data in EEPROM on the BMS board, not in the cell itself. When a new cell is installed, the BIOS reads stale EEPROM values from the previous battery's charge history and flags the health as poor or unknown. This is not a fault with the replacement cell. One full discharge-to-hibernate followed by an uninterrupted charge to 100% rewrites the learn cycle data and resolves the warning.
Aspire S3 shutting down at 20–30% battery shown on screen
This happens when the fuel gauge IC has not yet calibrated against the new cell's actual voltage curve. The gauge reports 20–30% remaining, but the cell voltage has already dropped below the BMS cutoff threshold under combined CPU and display load. The laptop shuts down because the real cell voltage hits the floor before the percentage readout catches up. Run two full discharge-to-hibernate and full-recharge cycles — after the second cycle the fuel gauge IC recalibrates and the reported percentage will align with actual cell voltage down to approximately 3.0V per cell.