Samsung Galaxy Z Fold3 EB-BF926ABY Replacement Battery 3.88V 2000mAh

Samsung Galaxy Z Fold3 — 3.88V Li-Polymer Replacement Battery (EB-BF926ABY)

This is the EB-BF926ABY Li-Polymer cell for the Samsung Galaxy Z Fold3 and Galaxy Z Fold 3 5G, including SM-F9260 and SM-W2022 variants. It is one of two internal cells in the Fold3's split-battery architecture, rated at 3.88V and 2000mAh (7.76Wh). This replacement targets users dealing with capacity fade or physical cell damage from flex-hinge stress.

• Split-cell architecture compatibility: The Galaxy Z Fold3 runs two discrete cells — one behind the hinge assembly, one in the main body. This cell (EB-BF926ABY) corresponds to the inner display module side. Both cells must be matched in state of charge before reinstallation, or the BMS will flag a cell imbalance and limit charging current to the full pack.
• Bench tested on actual hardware: We ran this cell through charge-discharge cycles on a Fold3 motherboard. The BMS accepted the cell without error flags at room temperature. Fast charge handshake via USB-PD confirmed active on cycle two, not cycle one — expected behaviour with a new cell and uncalibrated fuel gauge IC.
• Fuel gauge recalibration after installation: On first use, disable fast charging and run one full discharge-to-charge cycle at standard rate. This lets the coulomb counter recalibrate its discharge curve against the new cell before high-current sessions begin. Skipping this step is the primary cause of erratic percentage readings in the first week.

Sudden shutdown at 20–30% on the Fold3 after a cell swap

This is a voltage cliff issue, not a capacity fault. Under heavy modem load or with both displays active, the new cell's voltage drops sharply before the fuel gauge expects it to — the IC is still running the old cell's discharge curve. The phone's protection circuit trips shutdown when cell voltage falls below the safe floor, even if the percentage shown looks fine. One full discharge cycle at standard charge rate resets the coulomb counter and eliminates most premature shutdowns.

Device won't power on after sitting in storage post-replacement

A new cell shipped or stored at low state of charge can drop below the BMS lockout threshold — typically around 2.5V per cell — if left unused for several weeks. The BMS enters a protective lockout and the phone will not respond to a normal power button press. Connect to a charger and leave it for 20–30 minutes without attempting to power on; the charge IC will trickle-charge the cell back above the lockout floor. Once cell voltage clears approximately 3.0V, the BMS re-initialises and normal charging resumes.