MetroPCS A30 Replacement Battery 3.85V 3000mAh Li-Polymer

MetroPCS A30 / 5049Z — 3.85V Li-Polymer Replacement Battery

This is a 3.85V, 3000mAh (11.55Wh) lithium-polymer cell for the MetroPCS A30, A30 Plus, and 5049Z smartphones. It targets phones that no longer hold a charge, shut down unexpectedly, or won't power on after sitting in a drawer. Dimensions are 76.90 × 62.26 × 3.40mm — verify these against your existing cell before installing.

• A30 / 5049Z platform fit: The A30 and 5049Z share the same battery bay geometry, connector pinout, and charge IC handshake — one cell covers both. The A30 Plus uses the same footprint with the same 3.85V rail, so the BMS negotiation runs identically across all three variants.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the A30 platform. The BMS accepted the standard 5V/1A charge path without fault flags, and protection cutoffs fired correctly at both the high and low voltage thresholds.
• Fuel gauge recalibration on first cycle: On first use after installation, disable fast charging and run one full discharge-to-charge cycle at standard rate. This lets the fuel gauge IC map its coulomb counter against the new cell's actual discharge curve before fast charge pushes high current into an uncalibrated state.

Sudden shutdown at 20–30% on the replacement cell

This is a voltage cliff issue, not a capacity problem. Under peak modem or screen load, the cell voltage sags below the BMS protection threshold before the reported percentage reaches zero. The fuel gauge IC is still reading from the old cell's discharge curve stored in firmware. One full discharge cycle at standard rate lets the coulomb counter re-anchor to the new cell's actual voltage profile — most users stop seeing abrupt shutdowns after that single calibration cycle.

Phone reports wrong battery percentage after cell swap

The A30's fuel gauge IC stores a learned discharge curve from the old cell. When a new cell goes in, the IC keeps using that stale curve, so the percentage on screen drifts — often reading full too quickly or dropping suddenly. The fix is one uninterrupted discharge from 100% down to automatic shutdown, then a full charge without interruption. After that cycle, the coulomb counter resets its reference baseline to the new cell and percentage accuracy returns to normal.