About this replacement
Asus VivoBook 14 X407UA-1C — 11.1V Li-ion Replacement Battery (A31N1719)
This is an 11.1V, 2600mAh (28.86Wh) Li-ion battery for the Asus VivoBook 14 X407UA-1C and X507UA series laptops. It replaces OEM part numbers A31N1719, 0B110-00520200, 0B110-00520500, and A31L04Q. Fit it when the original cell no longer holds charge or the OS reports a health warning after years of shallow cycling.
- X407UA and X507UA platform fit: Both series share the same 11.1V three-cell battery bay, connector pinout, and BMS handshake protocol — one cell serves the full model range without modification.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on a VivoBook 14 unit. The BMS negotiated correctly with the EC, charge termination triggered at the right threshold, and the fuel gauge IC began reading accurately after two full cycles.
- Post-install calibration cycle: After fitting this battery, discharge the laptop normally until it hibernates at the low-voltage cutoff — do not interrupt. Then charge uninterrupted to 100%. This single cycle resets the BIOS battery learn cycle and clears the inaccurate health warning that appears after every cell swap on this platform.
BIOS reporting battery health as poor immediately after fitting this cell
The VivoBook EC reads health data stored in the outgoing cell's EEPROM and compares it against the new cell on first boot. Because the new cell carries factory EEPROM data rather than your system's learned values, the EC flags it as degraded or unknown. This is not a fault with the replacement cell. Running one full discharge-to-hibernate followed by an uninterrupted charge to 100% rewrites the learned data and clears the warning. After two to three cycles, the health indicator returns to normal.
Laptop shutting down at 20–30% charge shown on the VivoBook display
This happens when the fuel gauge IC has not yet calibrated against the new cell's actual voltage curve. The IC still uses the old cell's discharge profile, so it miscalculates the remaining capacity and triggers a low-voltage shutdown well before the cell is actually empty. The fix is two full calibration cycles: discharge to automatic hibernate cutoff each time, then charge fully without interruption. After the second cycle, the fuel gauge tracks the new cell's curve and the early shutdowns stop. If the issue persists past three cycles, check that the BIOS is not set to a charge limit below 100% under Power settings.