About this replacement
Samsung Galaxy Mega 2 SM-G750 Series — 3.8V Li-ion Replacement Battery (EB-BG750BBC)
This is a 3.8V, 2800mAh Li-ion replacement battery for the Samsung Galaxy Mega 2. It fits SM-G750, SM-G750A, SM-G750F, SM-G7508, and additional SM-G750 variants. Swap it in when the original cell can no longer hold a usable charge through a normal day.
- SM-G750 variant coverage: All SM-G750 variants listed share the same 3.8V battery bay, connector pinout, and BMS handshake protocol — one cell fits the entire range without modification.
- Bench tested on actual hardware: We ran this cell on an SM-G750F chassis. The BMS accepted charge handshake on first connection, stepped through CC/CV phases without interruption, and held voltage above the 3.4V threshold through full discharge cycling.
- Fuel gauge recalibration on first use: On first use after installation, disable fast charging and run one complete discharge-charge cycle. This allows the fuel gauge IC to map the new cell's discharge curve before high-current charging pushes current into an uncalibrated cell.
Sudden shutdown at 20–30% on the SM-G750 after a cell swap
The SM-G750's modem and display together draw peak current that a degraded or uncalibrated cell cannot sustain. When cell voltage drops below roughly 3.5V under that load, the BMS triggers a hard cutoff before the OS fuel gauge reaches zero. The fuel gauge IC is still reading a curve calibrated to the old cell, so the reported percentage is wrong at the point of shutdown. Run one full discharge to near 0% and a full charge to 100% — this recalibrates the coulomb counter against the new cell's actual voltage curve.
OS reporting wrong battery percentage after replacement
After fitting a new cell, the fuel gauge IC on the SM-G750 continues using the learned discharge model from the old battery. This mismatch causes the percentage to jump erratically or report full charge while the cell is still near 3.6V. The fix is a single full discharge-charge cycle with the screen on and no fast charging active. Once the coulomb counter resets against the new cell, percentage reporting stabilises within a few degrees of actual state of charge.