CECT V10 Replacement Battery 3.7V 750mAh Li-ion

CECT V10 — 3.7V Li-ion Replacement Battery

This is a 3.7V, 750mAh (2.78Wh) Li-ion replacement battery for the CECT V10 smartphone. It fits directly into the V10 battery bay and restores power to the device's core functions — calls, messaging, and basic applications. Use this when the original cell no longer holds a charge or fails to power the phone.

• CECT V10 fit: The V10 uses a compact 53.00 × 33.90 × 5.70mm cell format at 3.7V nominal. This battery matches that footprint and voltage rail, so the connector seats correctly and the device's charge IC sees the expected cell parameters.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the bench. The BMS held cutoff at the correct upper and lower voltage thresholds, and the charge IC accepted a full cycle without flagging an error state.
• Fuel gauge recalibration on first use: On first use after installation, disable any fast-charge mode for one complete discharge-to-charge cycle. This lets the fuel gauge IC recalibrate its coulomb counter against the new cell's discharge curve before high-current charging pushes current into an uncalibrated cell.

Sudden shutdown at 20–30% on the CECT V10 after a cell swap

A fresh cell has a slightly different voltage-to-capacity curve than the worn cell the fuel gauge IC was calibrated against. When the modem transmits or the screen peaks in brightness, it pulls a short current spike. If the IC thinks the cell is at 25% but the actual open-circuit voltage is close to the BMS lower cutoff, that spike drops voltage below the threshold and the phone shuts off instantly. One full discharge-charge cycle without fast charging recalibrates the coulomb counter to the new curve. After that cycle, the percentage reading tracks actual cell state more accurately and the early shutdowns stop.

CECT V10 not powering on after the battery sat in storage

Li-ion cells self-discharge in storage. If the cell voltage drops below approximately 2.5V, the BMS enters a protective lockout and blocks normal charging to prevent an unsafe charge into a deeply discharged cell. Plugging in a standard charger at that point shows nothing on screen — the phone appears completely dead. To recover, connect the charger and leave it for 20–30 minutes without attempting to power on; most charge ICs on budget smartphones apply a low trickle current to bring the cell back above the 2.8–3.0V re-enable threshold before switching to normal charge rate. If the phone still shows no response after that period, check that the charging cable is delivering voltage at the port rather than assuming the battery is faulty.