About this replacement
Asus X450 / X450V Series — 14.4V Li-ion Replacement Battery (A41-X550)
This is a 14.4V, 4400mAh (63.36Wh) Li-ion battery for the Asus X450, X450V, X450VB, X450VC, and over 160 additional X-series models. It replaces OEM part numbers A41-X550 and A41-X550A. The connector, BMS handshake, and cell voltage match the original Asus specification.
- X450 series compatibility: All listed X450 variants share the same 14.4V four-cell architecture, identical dock connector, and the same BMS communication protocol — which is why one part number covers the full range.
- Bench tested on actual hardware: We cycled this battery through charge, idle, and CPU-plus-display load on X450 hardware. The BMS held within spec under sustained load, and the charge IC accepted full current from cold start to termination.
- Post-install discharge cycle on the X450: After fitting, run the laptop on battery until it hibernates at low cutoff — then charge uninterrupted to 100% without interruption. This forces the BIOS battery learn cycle to reset against the new cell, clearing the inaccurate health warning that appears after every cell swap.
BIOS reporting poor battery health immediately after fitting a new cell
The X450 BIOS stores charge history and cell wear data in EEPROM. When a new cell is installed, that stored data no longer matches the actual cell state, so the BIOS flags the battery as degraded or unknown — even though the cell is fresh. This is not a fault with the replacement battery. Running one complete discharge-to-hibernate followed by a full uninterrupted charge gives the BIOS enough data to recalibrate. After one or two full cycles, the health reading normalises.
Laptop shuts down abruptly at 20–30% charge shown on screen
This happens when the fuel gauge IC is still calibrated to the old cell's discharge curve. The percentage shown is based on a voltage map that no longer matches the new cell, so the laptop hits the low-voltage cutoff before the gauge reaches zero. It is not a battery defect — it is a mismatch between the IC's stored profile and the new chemistry. Force a full discharge to hibernate cutoff, then charge to 100% without interruption. After two full calibration cycles, the gauge aligns to the new cell and the early shutdowns stop. Confirm cell voltage at full charge reads at or above 16.4V at the terminals.