About this replacement
Microsoft Surface Pro X 1876 — 7.58V Li-Polymer Replacement Battery (G3HTA056H)
This is a 7.58V, 4800mAh (36.38Wh) Li-Polymer replacement battery for the Microsoft Surface Pro X model 1876. It fits the slim 2-in-1 tablet chassis directly, using OEM part number G3HTA056H. Swap it when the original cell no longer holds a useful charge through a normal work session.
- Surface Pro X 1876 fitment: The 1876 chassis uses a specific connector orientation and BMS handshake tied to the G3HTA056H part number. Voltage must match the 7.58V nominal rail — the onboard power management IC will reject cells outside that spec and prevent the unit from powering on.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on a Surface Pro X 1876 unit. The BMS accepted the cell without fault codes, charge current ramped correctly through CC/CV stages, and the display reported percentage within normal variance after a recalibration cycle.
- Fuel gauge recalibration after install: After fitting this battery, run one full discharge to automatic shutoff — do not force-shutdown — then charge uninterrupted to 100%. The fuel gauge IC is still calibrated against the old cell's curve. That single full cycle resets it against the new cell and clears the inaccurate percentage readings that appear immediately after a swap.
Why the Surface Pro X shuts down at 15–25% after a battery swap
The Surface Pro X combines a high-resolution display and always-on LTE or Wi-Fi into a very thin chassis. Under combined load — screen at full brightness plus active wireless — the new cell draws enough current that voltage sags below the BMS cutoff threshold before the percentage counter reaches zero. The firmware reads a low-voltage trip as an empty cell, not a calibration error. One complete discharge-to-shutoff cycle followed by an uninterrupted charge to 100% aligns the fuel gauge IC to the new cell's actual voltage curve and moves the cutoff point back to below 5%.
Fast charging not available after battery replacement on Surface Pro X
The Surface Pro X uses USB-PD negotiation to determine charge rate — the charge controller needs at least one completed charge cycle on the new cell before it confirms the cell can accept higher current safely. Until that cycle runs, the system defaults to standard charge rate as a protection fallback. Connect the original Microsoft Surface charger, not a third-party USB-C adapter, for the first full charge. After one complete charge to 100%, USB-PD negotiation resets and fast charging becomes available again.