Alcatel One Touch S680 Replacement Battery 3.7V 750mAh

Alcatel One Touch S680 / OT-S680 — 3.7V Li-ion Replacement Battery

This is a 3.7V Li-ion cell rated at 750mAh (2.78Wh), built to fit the Alcatel One Touch S680 and OT-S680 smartphones. It replaces the original cell when the phone can no longer hold a usable charge, shuts down unexpectedly, or fails to power on after storage. Dimensions are 46.20 × 34.14 × 5.68mm — verify against your existing cell before fitting.

• One Touch S680 and OT-S680 fit: Both model designations refer to the same handset on different regional SKUs. The battery connector, physical footprint, and voltage rail are identical across both variants, so one cell covers either unit without modification.
• Bench tested on actual hardware: We cycled this cell through full charge and discharge on the S680 platform. The BMS accepted charge handshake normally, balanced to 4.2V at termination, and held the low-voltage cutoff at the expected floor without false tripping.
• Fuel gauge recalibration after install: On first use, disable any fast-charge mode and run one full discharge-to-charge cycle at standard rate. This lets the fuel gauge IC map the new cell's discharge curve before high-current charging is applied to an uncalibrated cell.

Sudden shutdown at 20–30% on the S680 after a cell swap

The S680's fuel gauge IC retains the discharge curve from the old, degraded cell. When a fresh cell is installed, the IC underestimates remaining capacity and triggers a low-voltage shutdown before the cell is actually depleted. The fix is one complete discharge-charge cycle at standard rate — the coulomb counter resets its baseline against the new cell's actual voltage curve. After that single cycle, the percentage readout stabilises and early shutdowns stop.

Phone won't power on after the battery sat in storage

Li-ion cells that drop below approximately 2.5V trigger a BMS lockout — the protection circuit disconnects the cell to prevent damage, and the phone shows no sign of life even on charge. Connect the phone to a low-current USB source (a PC port works better than a fast charger here) and leave it for 15–20 minutes. The BMS trickle-charges the cell back above the lockout threshold, then normal charging resumes. If the phone still does not respond after 30 minutes on a known-good cable, check the charge port for debris before replacing the cable.