About this replacement
Samsung Galaxy Tab S9 FE — 3.86V Li-Polymer Replacement Battery (EB-BX516ABY)
This is a 3.86V, 7750mAh lithium-polymer replacement battery for the Samsung Galaxy Tab S9 FE. It fits SM-X510, SM-X510N, SM-X516, and related variants. Install it when the original cell no longer holds adequate charge after repeated cycle aging.
- SM-X510 and SM-X516 series compatibility: Both Wi-Fi and LTE variants of the Tab S9 FE share the same battery bay dimensions, connector pinout, and BMS handshake protocol — this cell fits all of them without modification.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on a Tab S9 FE unit. The BMS accepted the cell on first connection, negotiated charge current correctly, and raised no protection flags during load testing across display and Wi-Fi simultaneous draw.
- Fuel gauge recalibration after swap: After installation, run the tablet down to automatic shutoff — do not manually power it off — then charge uninterrupted to 100%. This single full cycle resets the fuel gauge IC against the new cell's actual capacity curve and eliminates the percentage drift that appears immediately after a battery swap.
Tab S9 FE shutting down at 15–25% remaining after battery replacement
This happens when the fuel gauge IC still references the voltage curve of the old, degraded cell. Under combined display and Wi-Fi load, voltage drops faster than the gauge expects, and the protection circuit trips before the cell is actually empty. The OS reads 18% but the rail has already dipped below the cutoff threshold. Run one full discharge to automatic shutoff followed by an uninterrupted charge to 100% — this resyncs the gauge to the new cell's 3.86V nominal curve and stops premature cutoffs.
Fast charging unavailable on the Tab S9 FE after battery swap
The Tab S9 FE uses USB-PD negotiation to enable fast charge — the charge IC must complete at least one accepted full charge cycle before the device unlocks higher input current from a compatible adapter. If fast charge is absent immediately after installation, connect a USB-PD adapter rated at 25W or above and allow the tablet to charge fully without interruption. After that first complete cycle, fast charge resumes normally. Confirm the adapter output in its spec sheet — a standard 5V/2A brick will not trigger USB-PD negotiation regardless of how many cycles you run.