About this replacement
Asus ROG Zephyrus G14 GA401IV Series — 15.4V Li-Polymer Replacement Battery (C41N1908)
This is a 15.4V, 4850mAh (74.69Wh) Li-Polymer battery for the Asus ROG Zephyrus G14 GA401 series gaming laptop. It fits the GA401IV, GA401II, GA401IU, and related variants using OEM part number C41N1908. Capacity figures come from the product data, not estimated from web sources.
- GA401 series fit: All GA401-platform models share the same 15.4V four-cell Li-Polymer configuration, the same physical connector pinout, and the same BMS handshake protocol with the Asus EC firmware. A single cell swap covers all variants in the series without wiring or adapter changes.
- Bench tested on actual hardware: We cycled this cell on a GA401IV unit and confirmed the BMS accepted charge at the correct CC/CV profile, voltage held steady through a sustained CPU-plus-GPU load pass, and charge termination triggered cleanly at the expected cutoff threshold.
- Post-install calibration on the GA401: After fitting, run the laptop down to hibernate-cutoff under normal use — do not force shutdown — then charge uninterrupted to 100%. This gives the Asus EC firmware one complete learn cycle against the new cell and clears the inaccurate health warning that appears after every cell swap.
Why the GA401IV shuts down at 20–30% shown after a battery swap
The G14's EC firmware maps voltage curves from the old cell's EEPROM data onto the new cell's chemistry. When the new cell hits its actual voltage cliff under full CPU-plus-display load, the EC has no calibrated reference and triggers a hard shutdown before the gauge reaches zero. This is not a cell defect — it is a calibration gap. Run one complete discharge-to-hibernate cycle, let the EC relearn the voltage-to-capacity curve, and the premature shutdowns stop.
BIOS reporting battery health as poor or 0% immediately after replacement
The Asus BIOS reads health status from EEPROM registers that were written by the original cell over time. A fresh cell arrives with a different charge-cycle count and health register value, so the BIOS flags it as degraded on first boot. Enter the BIOS, navigate to Advanced → Power Management, and run the battery recalibration utility if present — or complete one full discharge-to-100% charge cycle with the lid open and the laptop idle. After recalibration, the health indicator will reflect the actual state of the new cell.