About this replacement
Samsung Galaxy Xcover 4 — 3.85V Li-ion Replacement Battery (EB-BG390BBE)
This is a 3.85V, 2500mAh Li-ion cell that replaces the original EB-BG390BBE battery in the Samsung Galaxy Xcover 4. It fits the SM-G390, SM-G390F, and SM-G390Y variants along with additional SM-G390 sub-models. The battery slots directly into the removable-back housing and connects via the standard three-pin contact strip.
- SM-G390 variant compatibility: All SM-G390 sub-models share the same battery bay dimensions, contact layout, and BMS handshake protocol — the fuel gauge IC communicates across the same three-pin interface regardless of regional firmware variant.
- Bench tested on actual hardware: We ran this cell on an SM-G390F unit and confirmed the BMS accepted the new cell without fault codes, fuel gauge initialisation completed within the first charge cycle, and the charge IC stepped through trickle, CC, and CV phases correctly.
- Fuel gauge recalibration on first use: After fitting this battery, disable fast charging in Settings and run one full discharge down to automatic shutdown, then charge uninterrupted to 100% — this gives the coulomb counter a clean baseline against the new cell's discharge curve before any high-current sessions.
Why the Xcover 4 reports wrong battery percentage after a cell swap
The Xcover 4 uses a coulomb counter that builds its discharge model against the original cell's impedance and capacity curve. When you fit a new cell, that stored model no longer matches what the hardware sees. The fuel gauge IC starts estimating from stale data, which produces percentage readings that jump or stall. One complete uninterrupted discharge-to-shutdown followed by a full charge resets the counter and anchors it to the new cell.
Sudden shutdown at 20–30% on the replacement cell
This happens when the cell voltage drops sharply under modem or screen load — a voltage cliff where the reported state of charge says 25% but the actual cell voltage has already fallen below the cutoff threshold the BMS enforces. Aged cells sag harder under load, but even new cells show this on first use if the fuel gauge is still running the old discharge curve. The fix is the same calibration cycle: full drain to automatic shutdown, then charge straight to 100% without interruption. After that cycle, the percentage and the real cell voltage track each other correctly.