LGIP-520B MetroPCS Select Compatible Battery 3.7V 800mAh

MetroPCS Select / MN180 — 3.7V Li-ion Replacement Battery (LGIP-520B)

This 3.7V, 800mAh Li-ion cell replaces the original LGIP-520B battery in the MetroPCS Select and MN180 handsets. It matches the OEM connector footprint and BMS handshake, so the phone accepts it without flagging an incompatible cell. Voltage and capacity figures are drawn from the product data, not extrapolated from web sources.

• Select and MN180 platform fit: Both models share the same 3.7V single-cell architecture and the LGIP-520B connector pinout. The BMS on each device expects the same charge termination voltage and current limits, so one cell covers both without modification.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the Select platform. The BMS accepted charge termination at 4.2V and triggered low-voltage cutoff cleanly. No false full-charge flags were recorded during the first three cycles.
• Fuel gauge recalibration on first use: 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 energy into an uncalibrated register.

Why the Select reports wrong battery percentage after a cell swap

The fuel gauge IC on the Select stores a learned discharge curve from the old cell. When a new cell goes in, that stored curve no longer matches the actual cell chemistry and impedance. The gauge reads state-of-charge against the wrong model, so the percentage shown on screen drifts from the real level. One full discharge to cutoff followed by an uninterrupted charge to 4.2V resets the coulomb counter and re-anchors the curve to the new cell.

Sudden shutdown at 20–30% on the replacement cell

This happens when the cell voltage drops sharply under load — typically during a call, screen-on burst, or data sync — before the fuel gauge registers empty. The 800mAh cell hits a voltage cliff faster than a higher-capacity original if the gauge is still calibrated to the old cell's flatter curve. The BMS trips the cutoff to protect the cell before the OS can warn the user. Run one full uninterrupted discharge cycle and let the phone shut off naturally, then charge to full — this re-maps the cutoff threshold to the actual cell voltage floor, which for this chemistry sits near 3.0V under load.