About this replacement
Samsung Galaxy A7 2018 — 3.85V Li-Polymer Replacement Battery (EB-BA750ABU)
This 3.85V, 3200mAh Li-Polymer battery replaces the original EB-BA750ABU cell in the Samsung Galaxy A7 2018. It fits the SM-A750F/DS, SM-A750FN/DS, and Galaxy A7 2018 Duos variants. Voltage and capacity match the OEM spec exactly — 3.85V nominal, 12.32Wh.
- SM-A750 variant coverage: The SM-A750F/DS and SM-A750FN/DS share the same battery bay dimensions (80.84 × 64.06 × 3.60mm), connector pinout, and BMS handshake protocol — one cell covers the full A7 2018 lineup including Duos models.
- Bench tested on actual hardware: We ran this cell through the SM-A750F charge cycle. The BMS accepted the charge handshake without a fault flag, held the 4.40V charge ceiling correctly, and the protection circuit tripped at the expected undervoltage threshold during deep-draw testing.
- Fuel gauge recalibration on first cycle: On first use after installation, disable fast charging and run one full discharge-to-charge cycle. This lets the fuel gauge IC map its coulomb counter against the new cell's actual discharge curve before high-current charging pushes current into an uncalibrated cell.
Sudden shutdown at 20–30% on the replacement cell
This is a voltage cliff problem, not a capacity problem. When the modem fires or the screen peaks, the cell must sustain voltage under a sharp current draw. A new cell that hasn't been calibrated to the fuel gauge IC can hit its BMS undervoltage cutoff while the OS still shows 20–30% remaining. The gauge is reading a stored curve from the old cell, not the new one. One complete discharge to auto-off followed by a full charge to 100% resets the coulomb counter and clears the mismatch.
USB fast charge not activating after battery replacement
The A7 2018 uses Samsung's Adaptive Fast Charging protocol, negotiated between the charge IC and the charger on each session. On a freshly installed cell, the BMS may flag the cell as unconditioned and restrict charge current to standard 5V/1A until it completes an initial cycle. If fast charge doesn't activate, confirm the charger output using a USB meter — it should step up to 9V. If it stays at 5V after one full cycle, switch cables and retest, as the A7 2018 charge IC is sensitive to cable resistance at higher voltages.