About this replacement
Samsung Galaxy XCover7 Pro — 3.88V Li-ion Replacement Battery (GH43-05270A)
This 3.88V, 3900mAh Li-ion battery replaces the original cell in the Samsung Galaxy XCover7 Pro (SM-G766B, SM-G766B/DS, SM-G766BU1). It matches OEM part numbers GH43-05270A and EB-BG766GBY. Rated at 15.13Wh, it restores full operating capacity to this rugged smartphone platform.
- XCover7 Pro platform fit: The SM-G766B variants share a fixed connector pinout and BMS handshake tied to Samsung's fuel gauge IC. All listed models use the same voltage rail and charge IC configuration, so one cell covers the full variant set without adapter changes.
- Bench tested on actual hardware: We cycled this battery through a full discharge-charge sequence on SM-G766B hardware. The BMS negotiated charge termination correctly, and the fuel gauge IC logged cell capacity without triggering fault codes at either charge entry or cutoff.
- First-cycle fast charge caution: On first use after installation, disable fast charging for one complete discharge-charge cycle. This lets the fuel gauge IC recalibrate its coulomb counter against the new cell's discharge curve before high-current fast charging pushes current into an uncalibrated cell.
Sudden shutdown at 20–30% on the XCover7 Pro after a cell swap
This is a voltage cliff issue, not a defective cell. The fuel gauge IC was calibrated to the old cell's discharge curve, so it misreads remaining capacity on the new cell. When the modem or display pulls a heavy load burst, the cell voltage drops faster than the gauge expects and the BMS triggers a protective shutdown before the reported percentage reaches zero. One full discharge-charge cycle — draining to automatic shutdown, then charging uninterrupted to 100% — resets the coulomb counter against the new cell's actual curve. After that cycle, the shutdown-at-percentage behaviour typically stops.
USB-PD fast charge not accepted on the first charge after installation
Some SM-G766B units refuse fast charge negotiation on the very first cycle with a new cell. The charge IC defaults to a conservative trickle rate when it cannot confirm the cell's internal resistance profile, which it learns during the first full cycle. Plug into a USB-PD charger after that initial full cycle completes and fast charge should negotiate normally. If fast charge still does not activate, check that battery saver mode is off — the XCover7 Pro locks charge rate to standard when battery saver is enabled.