Samsung Galaxy A50 EB-BA505ABN Replacement Battery 3.85V 3900mAh

Samsung Galaxy A50 SM-A505 — 3.85V Li-Polymer Replacement Battery (EB-BA505ABU)

This is a 3.85V, 3900mAh (15.02Wh) lithium-polymer replacement battery for the Samsung Galaxy A50 and SM-A505FM/DS. It fits the 2019 Galaxy A50 lineup and uses OEM part numbers EB-BA505ABN, EB-BA505ABU, and GH82-19269A. If your A50 no longer holds a charge or shuts down unexpectedly, this cell replaces the degraded original.

• SM-A505 series fit: Every SM-A505 variant shares the same battery bay dimensions, connector pinout, and BMS handshake protocol. The physical cell measures 80.60 × 62.35 × 4.26mm — no trimming or adapter needed across the A50 model range.
• Bench tested on actual hardware: We ran this cell on an SM-A505FM/DS through multiple charge cycles. The BMS accepted the Samsung charge protocol without rejection, and the protection circuit triggered correctly at the low-voltage cutoff threshold.
• Fuel gauge recalibration after install: 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 fast charge pushes high current into an uncalibrated cell.

Sudden shutdown at 20–30% on a freshly installed A50 cell

This happens when the fuel gauge IC is still calibrated to the old cell's discharge curve. The new cell hits a voltage cliff under screen-on or modem load — the voltage drops below the shutdown threshold even though the reported percentage looks safe. The A50's power management IC shuts the phone down to protect the cell, not because the battery is faulty. Run one full uninterrupted discharge until the phone shuts off, then charge to 100% without interruption — this resets the coulomb counter baseline.

USB-PD fast charge not accepted on the first cycle after replacement

After a cell swap, the BMS on the new battery starts in a conservative state. The A50's charge IC handshakes with the BMS before stepping up to fast charge current — if the BMS hasn't completed its first initialization cycle, the charger falls back to standard 5V input. This is not a fault with the battery or the charger. Complete one full standard charge cycle first, then fast charging will negotiate correctly on subsequent cycles.