About this replacement
HP Envy X360 15T-ED000 — 11.55V Li-Polymer Replacement Battery (BN03XL)
This is an 11.55V, 4050mAh (46.78Wh) lithium-polymer replacement battery for the HP Envy X360 15T-ED000 convertible laptop. It also fits the Envy X360 13-ay0360ng, 13-ay0007ca, 15-ed0006TX, and 23 additional Envy X360 variants sharing the same BN03XL platform. OEM part numbers include BN03XL, HSTNN-DB9N, L76965-2C1, L77034-005, and L76985-271.
- Envy X360 BN03XL platform compatibility: These models share the same 11.55V three-cell Li-Polymer configuration, identical connector pinout, and BMS handshake protocol. Swapping between ED and EW chassis variants works because HP standardised the BN03XL across this generation of 13-inch and 15-inch Envy X360 convertibles.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on an Envy X360 15T chassis. The BMS negotiated correctly, the charge controller accepted the cell without fault codes, and the protection circuit engaged at the expected low-voltage cutoff threshold.
- Post-install calibration on the Envy X360: After fitting, run one full discharge to hibernate-cutoff, then charge uninterrupted to 100%. This resets the BIOS battery learn cycle and clears the inaccurate health warning the firmware triggers automatically after any cell swap.
BIOS reporting battery health as poor immediately after replacement
HP's BIOS reads health data from EEPROM registers written by the original cell's embedded controller. When a new cell arrives with factory-default EEPROM values, the firmware compares them against the stored charge history and flags the battery as degraded or unknown. This is a data mismatch, not a fault with the new cell. Run the full discharge-to-hibernate then uninterrupted charge cycle described above. After two to three complete cycles, the BIOS learn cycle overwrites the stale EEPROM data and the health status normalises.
Laptop shutting down at 20–30% remaining after the battery swap
This happens because the fuel gauge IC is still calibrated to the old cell's voltage curve. The new cell has a steeper voltage cliff under combined CPU and display load, and the IC interprets that voltage drop as a lower state-of-charge than it actually is. The laptop cuts power before the cell is genuinely empty. To fix this, complete three full discharge-to-hibernate cycles without interruption. By the third cycle the fuel gauge IC has mapped the new cell's actual discharge curve and the shutdown threshold returns to the correct level near 5–8%.