About this replacement
Samsung SM-W750V / Ativ SE — 3.8V Li-ion 2600mAh Replacement Battery (B600BZ)
This is a 3.8V, 2600mAh Li-ion replacement cell for the Samsung SM-W750V, also sold as the Ativ SE and Ativ SE Neo (Huron). It uses OEM part number B600BZ and slots into the same battery bay without modification. Capacity matches the original spec at 9.88Wh.
- SM-W750V / Ativ SE platform fit: These four model variants share the same chassis, battery bay dimensions, and connector pinout. The BMS handshake voltage and thermistor line are identical across the group, so one cell covers the full range.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on an SM-W750V unit. The BMS accepted charge without fault codes, thermistor communication stayed active throughout, and the fuel gauge IC tracked state-of-charge across the full voltage window from 4.35V to 3.0V cutoff.
- First-cycle fast charge caution: On first use after installation, disable fast charging and complete one full discharge-to-charge cycle at standard rate. This lets the fuel gauge IC recalibrate its coulomb counter against the new cell's discharge curve before high-current charging is applied to an uncalibrated cell.
Why the Ativ SE reports wrong battery percentage after a B600BZ swap
The SM-W750V uses a coulomb-counting fuel gauge IC that builds its charge model against the specific cell installed. When you swap to a new B600BZ, the IC still holds the discharge curve data from the degraded original cell. It then applies that old curve to the new cell, which has different impedance and capacity characteristics. The result is percentage readings that are off by 10–20% until the IC recalibrates. One complete discharge cycle down to shutdown, followed by a full charge to 100%, resets the curve data and restores accurate reporting.
Sudden shutdown at 20–30% on the replacement cell
This happens when the modem radio or display fires a high-current draw and the cell voltage drops sharply under load. The phone's protection circuit reads this as an undervoltage event and cuts power before the percentage counter catches up. It is not a faulty cell — it is a fuel gauge IC that has not yet mapped the new cell's internal resistance. Run the phone through two full discharge-charge cycles at standard charge rate, and the IC will learn the actual voltage sag curve. After calibration, the shutdown threshold will align with real cell state, and cutoffs below 20% should stop.