About this replacement
Samsung SPH-A760 — 3.7V Li-ion Replacement Battery
This is a 3.7V Li-ion cell rated at 950mAh (3.52Wh), built as a direct swap for the Samsung SPH-A760 mobile phone. It fits the SPH-A760's original battery bay and connector. Voltage and capacity match the factory spec exactly.
- SPH-A760 platform fit: The SPH-A760 uses a single-cell 3.7V Li-ion pack with a specific contact arrangement on the battery door side. This cell matches that voltage rail and connector footprint — the BMS handshake runs at 3.7V nominal, so no negotiation mismatch occurs on power-on.
- Bench tested on actual hardware: We cycled this cell through a full discharge and charge sequence, monitoring BMS cutoff at both ends. The low-voltage cutoff tripped cleanly before cell stress occurred, and the charge termination cut correctly at top-of-charge — no runaway, no false full signal.
- Fuel gauge recalibration on first use: After installing a new cell, run one complete discharge down to auto-shutoff, then charge uninterrupted to 100% before normal use. The SPH-A760's fuel gauge IC was calibrated to the old cell's discharge curve — without one full cycle, percentage readings will drift mid-use.
Sudden shutdown at 20–30% on the SPH-A760 after cell replacement
This happens because the fuel gauge IC still references the discharge curve of the old, degraded cell. When the new cell reaches a voltage point the IC maps to 20–30% on the old curve, it signals a low-voltage emergency and cuts power — even though actual charge remains. The phone isn't faulty. One full discharge-to-shutoff followed by an uninterrupted charge resets the coulomb counter against the new cell. After that cycle, shutdowns at false-low percentages stop.
SPH-A760 not powering on after the replacement battery sat in storage
Li-ion cells self-discharge in storage. If the cell dropped below roughly 2.5V per cell, the BMS enters lockout mode to prevent charging a critically depleted cell — this looks identical to a dead battery or a broken phone. Connect the charger and leave it for 20–30 minutes without pressing the power button. Most BMS circuits allow a trickle recovery charge at this voltage. If the charge indicator appears and voltage climbs above 3.0V, normal charging will resume.