TLp029C1 Alcatel A30 Fierce Replacement Battery 3.85V 3000mAh

Alcatel A30 Fierce / OT-5049Z Series — 3.85V Li-Polymer Replacement Battery (TLp029C1)

This is a 3000mAh, 3.85V Li-Polymer cell replacing the OEM TLp029C1 battery in the Alcatel A30 Fierce and A30 Fierce LTE. It fits the OT-5049Z, OT-5049S, and the broader OT-5049 platform variants. Swap it in when the original cell no longer holds voltage under screen or modem load.

• OT-5049 platform fit: The A30 Fierce, A30 Fierce LTE, OT-5049Z, and OT-5049S all run the same battery bay geometry, connector pinout, and BMS handshake. One cell covers the full lineup because Alcatel used a shared power architecture across the 5049 series.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the OT-5049 platform. The BMS accepted the cell without error flags, and the fuel gauge IC began tracking state-of-charge from the first completed cycle.
• Fuel gauge recalibration on first use: On first use after installation, disable fast charging and run one full discharge-to-charge cycle at standard rate. The fuel gauge IC on the A30 Fierce calibrates its coulomb counter against the cell's actual discharge curve — fast charging before that cycle completes pushes current into an uncalibrated cell and leaves the percentage readout unreliable.

Sudden shutdown at 20–30% on the A30 Fierce after a cell swap

The OT-5049 platform pulls hard on the battery when LTE, the display, and background processes peak simultaneously. A new cell with an uncalibrated fuel gauge can report 25% remaining while actual cell voltage is already near the BMS low-voltage cutoff threshold. The BMS trips and the phone shuts off — not because the cell is faulty, but because the OS percentage does not match real voltage. Run two full discharge-charge cycles at standard charge rate and the coulomb counter aligns with the new cell's curve, pulling the reported percentage in line with actual voltage.

Phone reports wrong battery percentage after installing the TLp029C1 replacement

The A30 Fierce uses a fuel gauge IC that stores learned discharge data from the previous cell. After a swap, that stored curve no longer matches the new cell's chemistry profile. The result is percentage readings that jump erratically or read higher than the actual voltage warrants. Charge the phone to 100%, let it discharge fully until shutdown, then charge uninterrupted back to 100% — one complete cycle resets the IC's reference points. After that cycle, percentage reporting stabilises.