About this replacement
Samsung Galaxy A3 — 3.8V Li-Polymer Replacement Battery (EB-BA300ABE)
This is a 3.8V, 1900mAh Li-Polymer replacement battery for the Samsung Galaxy A3 smartphone. It fits SM-A3000, SM-A3009, SM-A300G, and related SM-A300 variants. Cross-references OEM part numbers EB-BA300ABE, GH43-04381A, and GH43-04381B.
- SM-A300 series compatibility: The SM-A300 lineup shares a single battery bay geometry, connector pinout, and BMS handshake protocol across its regional variants. One cell covers the full range without modification.
- Bench tested on actual hardware: We cycled this cell on an SM-A300 unit and confirmed BMS recognition, stable charge acceptance from 0% to 100%, and correct voltage reporting throughout the charge curve.
- Fuel gauge recalibration on first use: On first 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 discharge curve before high-current charging begins on an uncalibrated cell.
Why the Galaxy A3 reports wrong battery percentage after a cell swap
The Galaxy A3 uses a coulomb-counting fuel gauge IC that builds its capacity model against the original cell's discharge curve over hundreds of cycles. When you install a new cell, the IC is still referencing that old curve. It will misreport state-of-charge — often showing 100% early in a charge or dropping percentage faster than the actual cell voltage warrants. One complete discharge down to automatic shutdown, followed by a full uninterrupted charge to 100%, forces the IC to recalibrate its internal model against the new cell. After that cycle, percentage readings stabilise.
Sudden shutdown at 20–30% on a freshly installed cell
This is a voltage cliff issue, not a capacity issue. Under modem transmission load or screen-on bursts, the new cell's voltage drops sharply below the protection threshold before the fuel gauge reads zero. The BMS trips the output to protect the cell, and the phone cuts off with charge still showing on screen. Charge the phone fully, then run the fuel gauge recalibration cycle described above. If shutdowns persist past the first two full cycles, check that the battery connector is fully seated — a partial connection raises contact resistance and amplifies voltage sag under load, lowering the trip point to around 3.4V.