About this replacement
Samsung Galaxy XCover7 5G — 3.85V Li-ion Replacement Battery (EB-BG556GBY)
This is a 3.85V 3680mAh Li-ion battery for the Samsung Galaxy XCover7 5G (SM-G556B). It replaces part number EB-BG556GBY and GH43-05199A. Fit the Galaxy XCover 7 when the original cell has degraded, lost capacity, or stopped holding voltage under load.
- SM-G556B platform compatibility: The XCover7 5G uses a fixed 3.85V nominal rail with a BMS that checks cell impedance and connector ID on boot. This cell matches that spec exactly — connector pinout, impedance range, and BMS handshake all align with the SM-G556B board.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the SM-G556B board, monitoring BMS communication across the full state-of-charge range. The protection circuit flagged no faults and the fuel gauge IC tracked cell voltage without error after the first complete cycle.
- Fuel gauge recalibration on first use: On first use after installation, disable fast charging and run one full discharge-charge cycle at standard current. This lets the fuel gauge IC map the new cell's discharge curve before Samsung's adaptive fast charge pushes high current into an uncalibrated cell.
Sudden shutdown at 20–30% on the XCover7 5G replacement cell
The XCover7 5G draws a significant current spike when the 5G modem switches between bands or when the display peaks at full brightness. A new cell with a fuel gauge IC still calibrated to the old cell's discharge curve can report 25% remaining while actual cell voltage drops below the BMS cutoff threshold under that load. The BMS then triggers a hard shutdown to protect the cell — the phone reads this as a crash, not a low-battery event. One full calibration cycle — discharge to auto-off, then charge uninterrupted to 100% — resets the coulomb counter and eliminates this behaviour.
USB-PD fast charge not accepted on the first cycle after replacement
After fitting a new cell, some SM-G556B units fall back to standard 5V/1A charging and ignore the fast charge negotiation entirely. This happens because the charge IC re-evaluates cell impedance on the first cycle, and a new cell at full impedance sits outside the threshold the IC expects for fast charge admission. It is not a fault with the charger or the cable. Charge the phone once to 100% on standard current — the charge IC logs the new impedance baseline and fast charging re-enables automatically on the next session.