HP Chromebook X360 14 G1 SY03XL Replacement Battery 11.55V

HP Chromebook X360 14 G1 — 11.55V Li-Polymer Replacement Battery (SY03XL)

This 11.55V, 5150mAh (59.48Wh) Li-Polymer cell replaces the OEM SY03XL battery in the HP Chromebook X360 14 G1 and X360 14-DA series convertibles. It fits the 14-DA0011DX, 14-DA0021NR, and the broader 14-DA range that shares the same connector and BMS handshake. Also cross-references HSTNN-DB8X, L29913-221, L29913-2C1, L29959-002, and L29959-005.

• X360 14-DA series compatibility: Every 14-DA variant uses the same 3-cell Li-Polymer pack with an identical connector pinout and BMS communication protocol. Voltage rails, cell count, and the SMBus data lines are uniform across this sub-family, so one SKU covers the full range.
• Bench tested on actual hardware: We ran this cell on a Chromebook X360 14 G1 unit. The BMS handshook on first boot, reported cell chemistry correctly, and the charge controller accepted a full charge cycle without fault flags. No pack rejection errors were logged.
• Post-install calibration on ChromeOS: After fitting this battery, run the Chromebook down to auto-hibernate cutoff, then charge uninterrupted to 100%. ChromeOS fuel gauge IC calibrates against the new cell during this first full cycle — skipping it leaves the battery status widget reporting inaccurate percentages for weeks.

Why the Chromebook X360 shuts down at 20–30% after a battery swap

The fuel gauge IC on the motherboard stores a learned discharge curve from the original cell. When a new cell goes in, that stored curve no longer matches the actual voltage-versus-capacity profile of the fresh pack. At around 20–30% indicated charge, the new cell's open-circuit voltage crosses a threshold the IC misidentifies as critically low, triggering an immediate shutdown. Running two or three full discharge-to-hibernate, then charge-to-100% cycles forces the IC to rebuild its discharge model against the new chemistry. After three cycles, shutdown-at-percentage behaviour typically resolves without any firmware changes.

BIOS or ChromeOS reporting battery health as "Unknown" or "Poor" after replacement

The SY03XL pack carries EEPROM data — manufacturer ID, cycle count, rated Wh — that ChromeOS reads via SMBus and compares against a known-good profile. A new cell resets those registers, and the OS interprets the mismatch as a degraded or unrecognised battery. This is a firmware read issue, not a fault with the cell itself. Run the full discharge-then-charge learn cycle once; the health indicator resets to normal after ChromeOS has logged at least one complete charge event from the new pack's EEPROM baseline.