MyPhone 1080 Replacement Battery 3.7V 1200mAh MP-S-V

MyPhone 1080 / 9010 / 9015TV / 8920 Series — 3.7V Li-ion Replacement Battery (MP-S-V)

This is a 3.7V 1200mAh Li-ion cell built to the MP-S-V specification, measuring 62.00 × 38.00 × 4.50mm. It fits the MyPhone 1080, 9010, 9015TV, and 8920, along with two additional models in the same family. Install it when the original cell can no longer hold enough charge to get through a normal day.

• Cross-model fit — 1080 to 9015TV: These MyPhone handsets share the same battery bay dimensions, connector pinout, and 3.7V nominal rail. One cell covers the entire group without modification.
• Bench tested on actual hardware: We cycled the MP-S-V cell through charge and load on the bench. The BMS held protection thresholds correctly and accepted a full charge without tripping the overcurrent cutoff.
• Fuel gauge recalibration on first use: On first installation, disable any fast-charge mode and run one complete discharge-to-charge cycle at standard current. This lets the fuel gauge IC map its coulomb counter against the new cell's actual discharge curve before higher charge rates are applied to an uncalibrated cell.

Why the MyPhone 1080 reports wrong battery percentage after a cell swap

The fuel gauge IC on the MyPhone 1080 stores a learned discharge curve from the old cell. When a new cell goes in, the IC still references that old curve, so the percentage it reports is off — often reading 100% when the cell is not full, or dropping fast in the mid-range. The fix is one full discharge from 100% down to automatic shutdown, followed by a full uninterrupted charge. After that single cycle, the coulomb counter recalibrates against the new cell and percentage readings stabilise.

Sudden shutdown at 20–30% on the replacement cell

This is a voltage cliff issue, not a capacity problem. Under peak load — mobile data, a bright screen, or a call — the cell voltage drops faster than the fuel gauge IC expects, hitting the BMS undervoltage cutoff while the displayed percentage still reads 20–30%. It happens most often in the first few cycles before the gauge IC has enough data to predict the new cell's sag curve accurately. Run two to three full discharge-charge cycles at normal use intensity and the shutdowns will move closer to the actual low-voltage floor, typically around 3.0V under load.