Samsung NP-SF511 Replacement Battery 11.1V 5900mAh AA-PN3NC6F

Samsung NP-SF511 / QX410 Series — 11.1V Li-Polymer Replacement Battery (AA-PN3NC6F)

This is an 11.1V 5900mAh (65.49Wh) lithium-polymer replacement battery for the Samsung NP-SF511, QX310, QX410, and QX411 laptop series. It replaces OEM part numbers AA-PN3NC6F, AA-PN3VC6B, BA43-00270A, and BA92-07034A. The cell dimensions are 210.00 × 100.40 × 12.25mm — measure your original before fitting if you are unsure which variant is installed.

• NP-SF511 / QX series compatibility: These models share the same battery bay dimensions, connector pinout, and BMS handshake protocol, which is why a single cell services the entire platform. The 11.1V rail matches the voltage regulation circuitry common across this generation of Samsung ultraportables.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on an NP-SF511 unit. The BMS negotiated correctly, charge termination triggered at full capacity, and the protection circuit responded normally to simulated over-discharge events.
• Post-installation calibration on Samsung NP-SF511: After fitting, run one full discharge until the laptop hibernates on low-battery cutoff, then charge uninterrupted to 100%. This resets the BIOS battery learn cycle and clears the inaccurate health warning that appears after every cell swap on this platform.

BIOS reporting poor battery health immediately after fitting a new cell

Samsung's BIOS on the NP-SF511 and QX series reads EEPROM data embedded in the original battery to track wear history. When a new cell is installed, that EEPROM data either doesn't match or shows an unfamiliar signature, so the BIOS flags the battery as degraded or unknown — even though the cell is new. This is not a fault with the replacement. Running one full discharge-to-hibernate cycle followed by an uninterrupted charge to 100% prompts the BIOS to write fresh calibration data and clear the warning on the next boot.

Laptop shuts down abruptly while the OS still shows 20–30% charge remaining

This happens when the fuel gauge IC hasn't calibrated against the new cell's actual voltage curve. The IC was tuned to the old, degraded cell and miscalculates the remaining capacity on a fresher cell. Under full CPU and display load, the voltage drops faster than the gauge predicts, and the laptop hits the hardware low-voltage cutoff before the OS percentage reaches zero. To fix it, let the laptop discharge fully to automatic hibernate, then charge to 100% without interruption — repeat for two to three cycles until the OS percentage tracks accurately. After calibration, the shutdown should no longer occur above 5–8% remaining.