About this replacement
Samsung Galaxy Note 20 — 3.88V Li-Polymer Replacement Battery (EB-BN980ABY)
This 3.88V, 4200mAh Li-Polymer cell replaces the original EB-BN980ABY battery in the Samsung Galaxy Note 20 and Note 20 5G. It fits SM-N981N, SM-N981W, and the broader Note 20 model range. Capacity matches the factory spec at 16.3Wh.
- Note 20 and Note 20 5G compatibility: Both variants share the same battery bay dimensions, connector pinout, and BMS handshake protocol. The EB-BN980ABY part number covers the full SM-N980 and SM-N981 series, so one cell works across both the LTE and 5G builds.
- Bench tested on actual hardware: We cycled this cell through a full discharge and charge sequence on SM-N981 hardware. The BMS accepted the cell without error flags, charge IC handshake completed normally, and the fuel gauge IC began tracking state of charge from the first cycle.
- Fuel gauge recalibration on first use: After installation, disable fast charging and run one complete discharge-charge cycle at standard rate. The fuel gauge IC on the Note 20 calibrates its coulomb counter against the cell's discharge curve — skipping this step on a fresh cell can leave the IC reading against the old degraded curve.
Sudden shutdown at 20–30% after a Note 20 cell swap
This is a voltage cliff issue, not a capacity fault. The Note 20's modem and display draw current spikes the new cell handles differently than the degraded original. The fuel gauge IC still holds the old discharge curve in memory and misreads the remaining voltage headroom. One full discharge to automatic shutoff followed by an uninterrupted charge to 100% forces the coulomb counter to reset against the new cell's actual voltage profile.
USB-PD fast charge not accepted on the first cycle after replacement
Some Note 20 units will not negotiate the 25W fast charge protocol with a new cell on the very first charge. The BMS on the replacement cell starts in a conservative state and may reject the high-current handshake until it confirms cell voltage is stable above 3.5V. Charge once at standard 5W from below 20% to above 90%, then reconnect the fast charger — the BMS typically accepts the 25W profile from that point forward.