About this replacement
Samsung Galaxy A15 4G 2024 — 3.85V Li-Polymer Replacement Battery (EB-BA156ABY)
This is a 3.85V, 5000mAh Li-Polymer replacement battery for the Samsung Galaxy A15 4G 2024. It fits SM-A155F/N, SM-A155F/DSN, SM-A155M/N, and 18 additional regional variants sharing the same battery bay and connector. OEM part number EB-BA156ABY, with GH82-33639A as the corresponding service assembly reference.
- SM-A155 series fit: All listed SM-A155 variants use the same battery bay dimensions (87.70 × 63.70 × 5.00mm), the same flex connector pinout, and the same BMS handshake voltage thresholds — which is why one cell covers the full regional lineup without modification.
- Bench tested on actual hardware: We ran this cell on an SM-A155F unit and confirmed the BMS accepted the handshake on first boot, charge IC engaged correctly, and the coulomb counter initialised without error flags in the battery stats log.
- Fuel gauge recalibration on first cycle: On first use after installation, disable fast charging and run one full discharge down to automatic shutdown, then charge to 100% on standard 5W. This gives the fuel gauge IC one clean reference cycle against the new cell's discharge curve before high-current charging is introduced.
Sudden shutdown at 20–30% on the Galaxy A15 after a cell swap
This is a voltage cliff issue, not a capacity defect. Under peak modem load or a bright-screen burst, a new cell that hasn't been calibrated can sag below the BMS cutoff threshold while the fuel gauge still reads 20–30%. The phone cuts power because the instantaneous voltage drops below approximately 3.4V at the terminals, even though the reported state-of-charge looks healthy. One full discharge-charge cycle without fast charging lets the coulomb counter map the actual cell curve and eliminate the gap between reported and real voltage.
USB-PD fast charge not recognised on first cycle after replacement
After a cell swap, the charge IC on the A15 sometimes refuses to negotiate fast-charge current on the first cycle because the BMS presents a high-impedance state until it completes one baseline charge pass. Plug into a standard 5W charger first — not the 25W adapter — and allow a full charge to 100%. Once that baseline pass is complete, the BMS lowers its impedance, the charge IC renegotiates the USB-PD contract, and fast charging activates normally from the second cycle onward.