About this replacement
Samsung SPH-I700 / SGH-I700 — 3.7V Li-ion Replacement Battery (BEX134KSE)
This is a 3.7V Li-ion cell rated at 1700mAh (6.29Wh), built to the same form factor as the original Samsung BEX134KSE / BST134ASE. It fits the SPH-I700 and SGH-I700 smartphones. The physical dimensions — 98.24 x 57.00 x 8.52mm — match the battery bay on both variants without modification.
- SPH-I700 and SGH-I700 fit: Both models share the same battery bay dimensions, connector pinout, and charge management circuit. One cell covers both variants — no adapter or wiring change needed.
- Bench tested on actual hardware: We ran the cell through full charge and discharge cycles on the SPH-I700 platform. The BMS accepted charge without fault flags, and the protection circuit tripped correctly at low-voltage threshold during discharge stress testing.
- Fuel gauge recalibration on first cycle: After installation, run the phone to near-empty and charge it fully in one uninterrupted pass before enabling any fast-charge mode. The fuel gauge IC on these early-2000s devices reads the discharge curve to set its internal reference — skipping this step causes percentage jumps and early shutdowns on the new cell.
Sudden shutdown at 20–30% on the SPH-I700 after a cell swap
The SPH-I700's charge management IC was calibrated against the original cell's internal resistance profile. A new cell has lower impedance, so the fuel gauge misjudges the remaining capacity and triggers a low-voltage shutdown before the display reaches 0%. This is not a defective battery — it's a recalibration gap. Run one complete discharge to 3.0V cutoff followed by a full uninterrupted charge. After that cycle, the coulomb counter resets its reference against the new cell and percentage reporting stabilises.
Phone not powering on after the replacement battery sat in storage
Li-ion cells stored below approximately 2.5V per cell trigger BMS lockout — the protection circuit opens and blocks current flow to prevent further discharge damage. The phone will show no response to the power button even with the charger connected. To recover, connect to a charger and leave it for 20–30 minutes without pressing anything — the charge IC delivers a low-current trickle that lifts the cell voltage above the BMS re-enable threshold. Once the voltage crosses roughly 2.7V, the BMS closes and normal charging resumes.