T-Mobile Rogue CPLD-365 Compatible Battery 3.8V 1500mAh

T-Mobile Rogue / 3320A — 3.8V Li-Polymer Replacement Battery (CPLD-365)

This is a 3.8V, 1500mAh lithium-polymer replacement battery for the T-Mobile Rogue (model 3320A). It replaces OEM part number CPLD-365. The cell restores power to a phone that no longer holds a charge or fails to turn on.

• Rogue / 3320A fit: Both model designations share the same battery bay dimensions, connector pinout, and BMS handshake protocol. This cell measures 65.30 × 47.04 × 4.12mm — the same footprint as the original CPLD-365 pack.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the bench. The BMS accepted the charge IC handshake without fault flags, and the protection circuit tripped correctly at the low-voltage cutoff threshold. No thermal anomalies were recorded during the charge phase.
• First-cycle fuel gauge recalibration: On first use after installation, disable fast charging and run one full discharge-to-charge cycle. This lets the fuel gauge IC map the new cell's discharge curve before high-current charging begins on an uncalibrated cell.

Why the Rogue reports wrong battery percentage after a cell swap

The fuel gauge IC in the Rogue uses a coulomb counter calibrated against the original cell's discharge curve. When a new cell goes in, the stored curve no longer matches the actual cell chemistry. The IC reads voltage offsets as incorrect state-of-charge values, so the displayed percentage drifts — often reading full when it isn't. One complete discharge below 10% followed by a full charge to 100% forces the IC to rebuild its reference curve against the new cell.

Sudden shutdown at 20–30% on the replacement cell

This happens when the cell voltage drops below the modem's or screen's minimum operating threshold under load — even though the fuel gauge still shows charge remaining. A fresh lithium-polymer cell has a steeper voltage cliff early in its life, before the internal resistance settles. The phone's power management IC sees voltage sag and triggers an emergency shutdown before the gauge catches up. After two or three full charge cycles, the cell's internal resistance stabilises and the shutdowns stop.