MetroPCS Quattro 4G Replacement Battery CPLD-74 3.7V 2800mAh

MetroPCS Quattro 4G / CP5860EM — 3.7V Li-ion Replacement Battery (CPLD-74)

This is a 3.7V, 2800mAh Li-ion replacement battery for the MetroPCS Quattro 4G and CP5860EM smartphones. It replaces OEM part number CPLD-74 when the original cell has degraded, lost capacity, or failed to hold a charge. Dimensions are 65.30 × 49.95 × 10.00mm — confirm physical fit before installing.

• Quattro 4G and CP5860EM compatibility: Both models run the same 3.7V single-cell architecture with the same connector footprint and BMS handshake, so one cell fits both. The charge IC expects the same cutoff thresholds across the platform.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the CP5860EM platform. The BMS accepted the cell without fault flags, and the charge IC reached full termination voltage without interruption.
• First-cycle fast charge protocol: On first use after installation, disable fast charging for one complete discharge-charge cycle. This lets the fuel gauge IC recalibrate against the new cell's discharge curve before high-current charging pushes current into an uncalibrated cell.

Why the Quattro 4G reports wrong battery percentage after a cell swap

The fuel gauge IC on the Quattro 4G uses a coulomb counter calibrated to the discharge curve of the original cell. When a new cell goes in, the stored curve no longer matches actual cell chemistry, so the percentage reading drifts. The gauge reports full charge earlier than the cell is actually full, or it drops sharply under modem or screen load. One full discharge to auto-off followed by a complete uninterrupted charge resets the counter against the new curve. After that cycle, percentage readings stabilise.

Sudden shutdown at 20–30% on the replacement cell

This happens when the cell voltage drops below the BMS cutoff threshold under load — even though the fuel gauge still shows remaining capacity. On the Quattro 4G, the LTE modem and display together can pull enough current to cause a rapid voltage sag on a cell the gauge hasn't fully mapped yet. The phone shuts down to protect the cell, not because the capacity is gone. Run one full calibration cycle first, then check whether shutdowns persist below 3.4V under load — if they do, the cell itself may have a high internal impedance.