About this replacement
Samsung Galaxy Ace 3 GT-S7270 / GT-S7272 — 3.8V Li-ion Replacement Battery (EB-B100AE)
This is a 3.8V 1500mAh Li-ion replacement battery for the Samsung Galaxy Ace 3. It fits the GT-S7270 and GT-S7272 variants and crosses to OEM part numbers B100AE, GH43-03948B, and EB-B100AE. Pull the back cover, swap the cell, and the phone powers on without any tools.
- GT-S7270 and GT-S7272 compatibility: Both variants use the same 3.8V single-cell architecture, the same connector pinout, and the same BMS handshake protocol — one battery fits both without modification.
- Bench tested on actual hardware: We ran this cell through full charge and discharge cycles on a GT-S7270. The BMS accepted the charge IC handshake on first connection, and the protection circuit triggered correctly at the low-voltage cutoff threshold.
- Fuel gauge recalibration on first cycle: On first use after installation, disable fast charging and run one complete discharge-charge cycle down to automatic shutdown and back to 100%. This lets the fuel gauge IC map the new cell's discharge curve before high-current charging pushes current into an uncalibrated state.
Sudden shutdown at 20–30% on the Galaxy Ace 3 after a cell swap
The Galaxy Ace 3 fuel gauge IC stores a discharge curve calibrated to the original cell. A new cell has a slightly different internal resistance profile, so the IC misreads the remaining capacity. When the modem, screen backlight, or GPS draw a short current spike, the phone's reported 25% is already below the real voltage floor. The phone shuts down to protect the cell even though the percentage looks safe. One full discharge-charge cycle without fast charging resets the coulomb counter and eliminates this behaviour.
Phone warm near the battery compartment during the first charge
A new Li-ion cell arrives with slightly higher internal impedance than a broken-in cell. The charge IC on the Ace 3 pushes current at the same rate it used with the old, lower-impedance cell, so a fraction more energy converts to heat in the first few cycles. The warmth is localised to the back cover near the battery and drops off after two or three full cycles as impedance settles. If the back cover becomes hot to the touch — not just warm — disconnect the charger and let the cell rest at room temperature before continuing.