Alcatel 1 Dual SIM TLI019D7 Replacement Battery 3.8V 1900mAh

Alcatel 1 Dual SIM — 3.8V Li-ion Replacement Battery (TLI019D7)

This 3.8V, 1900mAh Li-ion battery replaces the TLI019D7 cell in the Alcatel 1 Dual SIM smartphone. It restores capacity lost to cell ageing and fits the original battery bay without modification. Voltage and physical dimensions match the OEM spec: 87.40 × 34.92 × 4.70mm.

• Alcatel 1 Dual SIM fit: The TLI019D7 uses a single-cell 3.8V nominal configuration with a specific connector pinout tied to the phone's charge IC. Any cell outside this voltage and connector spec will not complete the BMS handshake on the mainboard.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the Alcatel 1 Dual SIM mainboard. The BMS handshake completed on first connection, charge current ramped correctly from trickle to CC/CV, and cutoff triggered at the expected 4.35V charge ceiling.
• Fuel gauge recalibration on first use: After fitting this cell, disable fast charging and run one full discharge-to-charge cycle before normal use. The fuel gauge IC is still calibrated to the old cell's discharge curve. One complete cycle lets it map the new cell's voltage profile before high-current charging is applied.

Why the Alcatel 1 Dual SIM reports wrong battery percentage after a cell swap

The fuel gauge IC uses a coulomb counter and a stored discharge curve to calculate state of charge. When you swap the cell, the IC still references the old cell's curve — which no longer matches the new cell's actual voltage-to-capacity relationship. The result is percentage readings that jump, stall, or read 100% while the phone shuts down minutes later. One full discharge below 10% followed by a complete charge to 100% forces the IC to rewrite its reference curve against the new cell.

Sudden shutdown at 20–30% on the replacement cell

This is a voltage cliff problem, not a capacity problem. Under peak load — active call, mobile data, or screen at full brightness — the cell's internal resistance causes a brief voltage sag that dips below the BMS cutoff threshold, even though the coulomb counter still shows charge remaining. The phone interprets the sag as a critical low-voltage event and shuts down immediately. Letting the replacement cell complete two full charge cycles reduces internal resistance at the surface layer and raises the voltage floor under load back above the cutoff point.