About this replacement
Asus ZenBook NX500 Series — 11.4V Li-Polymer Replacement Battery (C32N1340)
This 11.4V lithium-polymer battery carries 8200mAh (93.48Wh) of capacity and fits the Asus ZenBook NX500, NX500J, NX500JK, and over 29 additional NX500-series configurations. It replaces OEM part numbers C32N1340 and 0B200-00940100. If your original cell has degraded past the point of holding a usable charge, this is the direct swap.
- NX500 series compatibility: Every NX500 variant listed here shares the same three-cell Li-Polymer architecture, the same 11.4V nominal rail, and the same 0B200-00940100 connector and BMS handshake. Asus kept that spec consistent across the NX500J and NX500JK lines, so one cell covers the whole family.
- Bench tested on actual hardware: We ran charge and discharge cycles against the NX500's BMS and confirmed the protection circuit communicates correctly — charge termination triggers at full capacity and the BMS does not flag an unrecognised cell error during initialisation.
- First-cycle calibration on the NX500: After fitting, run the laptop on battery until it hits hibernate cutoff, then charge uninterrupted to 100% without interruption. This completes one full learn cycle and resets the BIOS fuel gauge against the new cell's actual capacity — skipping it leaves the health indicator inaccurate for weeks.
Why the NX500 BIOS reports poor battery health immediately after a cell swap
The NX500's BIOS reads battery health from EEPROM data embedded in the original cell. When you fit a new cell, that EEPROM is blank or mismatched, so the BIOS flags the battery as degraded or unknown before any cycles have run. This is a firmware read issue, not a fault with the replacement cell. One complete discharge-to-hibernate followed by an uninterrupted charge to 100% lets the BIOS write new reference data. After that single learn cycle, the health status updates correctly.
NX500 shutting down at 20–30% charge remaining
This happens when the cell voltage drops sharply under combined CPU and display load — the fuel gauge shows 20–30% remaining, but the actual cell voltage has already fallen below the BMS cutoff threshold. The gauge was calibrated to the old cell's discharge curve and no longer maps accurately to the new chemistry. Run a full discharge-to-hibernate cycle followed by a complete uninterrupted charge to 100% to force the fuel gauge IC to re-map against the new cell. After two to three of these calibration cycles, the shutdown point should stabilise at or below 5% remaining.