TLp034B2 Alcatel One Touch Hero Replacement Battery 3.8V 3400mAh

Alcatel One Touch Hero / Hero N3 — 3.8V Li-Polymer Replacement Battery (TLp034B2)

This 3.8V, 3400mAh Li-Polymer cell replaces the original TLp034B2 / TLp034B1 battery in the Alcatel One Touch Hero, Hero N3, OT-8020D, and One Touch 8020 series. It restores full charging capacity to phones where the original cell has degraded. Dimensions are 95.35 × 57.17 × 4.19mm — measure your existing cell before ordering if you are unsure of your variant.

• One Touch Hero and Hero N3 compatibility: Both the Hero and Hero N3 share the same battery bay dimensions and 3.8V power rail. The TLp034B2 and TLp034B1 part numbers are interchangeable across these variants — the BMS handshake and connector pinout are identical between them.
• Bench tested on actual hardware: We ran this cell through full charge and discharge cycles on the OT-8020D. The BMS engaged protection correctly at low-voltage cutoff, and charge termination triggered cleanly at 4.35V without overrun.
• Fuel gauge recalibration on first use: On first installation, disable fast charging and complete one full discharge down to auto-shutdown, then charge uninterrupted to 100%. This gives the phone's coulomb counter a clean reference cycle against the new cell's actual discharge curve before fast-charge currents are applied.

Sudden shutdown at 20–30% on the One Touch Hero after a cell swap

This happens because the fuel gauge IC is still running the discharge model it built against the old, degraded cell. The new cell has a steeper voltage curve in the lower charge window, so the phone reads 25% but the actual cell voltage under screen or modem load drops below the system cutoff threshold. The fix is a full calibration cycle — drain the phone to shutdown, then charge to 100% without interruption. After one complete cycle, the coulomb counter remaps its curve and the shutdowns stop.

Phone feels warm near the battery during the first few charges

A fresh Li-Polymer cell has slightly higher internal impedance than a broken-in cell, so the charge IC dissipates more heat converting that resistance during the constant-current phase. This is normal for the first two to three charge cycles and decreases as the cell's impedance settles. If the phone remains noticeably warm after five or more full cycles, check that the rear cover is seated flush — trapped air reduces heat dissipation. Warmth that persists beyond the CC phase into trickle charge is the signal to investigate further.