About this replacement
HP Pro X2 612 G2 — 7.7V Li-Polymer Replacement Battery (SE04XL)
This is a 7.7V, 5300mAh (40.81Wh) Li-Polymer cell for the HP Pro X2 612 G2 detachable 2-in-1. It fits models including 1LA51UT, 1FX32LT, L5H64EA, and 1KZ49PA, plus 83 additional variants. It replaces OEM part numbers SE04XL, 860708-855, 860724-2B1, 860724-2C1, and HSTNN-DB7Q.
- Pro X2 612 G2 platform fit: All covered variants share the same 7.7V battery rail, SE04XL connector pinout, and BMS handshake protocol. Swapping across these SKUs does not require firmware changes — the tablet's power controller reads the same cell ID.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on a Pro X2 612 G2 unit. The BMS accepted the cell without fault flags, balancing kicked in correctly across the polymer cell stack, and charge termination landed at the expected 8.7V cutoff.
- Post-install calibration cycle: After installing, run the tablet down until it hibernates on its own, then charge uninterrupted to 100% without using the device. This resets the BIOS battery learn cycle and clears the inaccurate health warning that appears after every cell swap.
BIOS reporting poor battery health immediately after replacement
The HP Pro X2 612 G2 stores health data from the previous cell in its EEPROM. When a new cell goes in, the BIOS compares live readings against that stored baseline and flags a mismatch as degraded health. This is not a fault with the replacement cell — it is stale data from the original battery. Running one full discharge-to-hibernate followed by an uninterrupted charge to 100% overwrites the learn cycle and resolves the warning. If the flag persists after two full cycles, check BIOS under Power → Battery Health Manager and confirm the charge limit is not set to 80%.
Tablet shuts down at 20–30% shown on the fuel gauge
This happens when the fuel gauge IC has not yet calibrated against the new cell's discharge curve. The old curve stored in the IC predicts a voltage floor that does not match the new polymer cell, so the OS calls a shutdown before the cell is actually depleted. It is not a faulty cell — it is a calibration lag. Run two to three full discharge-to-hibernate and full charge cycles without interrupting the charge. After those cycles, the fuel gauge re-maps to the new cell and shutdown will not occur above 8–10% remaining.