Alcatel TLi016D7 Replacement Battery 3.85V 1550mAh

Alcatel U3 2018 4G / OT-4055U / OT-4055J — 3.85V Li-ion Replacement Battery (TLi016D7)

This is a 3.85V, 1550mAh (5.97Wh) Li-ion replacement battery for the Alcatel U3 2018 4G, OT-4055U, and OT-4055J smartphones. It replaces the OEM part TLi016D7 directly. Fit this battery when the original cell no longer holds a charge or the phone shuts down unexpectedly under load.

• OT-4055U and OT-4055J platform fit: Both model variants use the same 3.85V voltage rail, connector pinout, and BMS handshake protocol — one battery covers the full OT-4055 range without modification.
• Bench tested on actual hardware: We ran charge and discharge cycles on the OT-4055U. The BMS accepted charge current correctly, thermal thresholds tripped at expected temperatures, and the protection circuit responded normally to simulated load spikes from the modem and display.
• Fuel gauge recalibration on first use: Disable fast charging for the first full discharge-charge cycle after fitting this battery. The fuel gauge IC on the U3 2018 4G calibrates its coulomb counter against the cell's discharge curve — running a slow cycle first prevents the percentage readings from drifting during early use.

Sudden shutdown at 20–30% on the Alcatel U3 2018 4G

The OT-4055 modem and display pull current spikes that a worn or deeply cycled cell cannot sustain. When cell voltage drops below roughly 3.5V under that instantaneous load, the BMS cuts output to protect the cell — even if the OS still reads 25% on the gauge. A fresh TLi016D7 cell has lower internal resistance and holds voltage through those spikes. After fitting the replacement, run one full discharge-charge cycle so the fuel gauge IC maps the new cell's actual voltage curve before reporting percentages to Android.

Phone not powering on after the battery sat discharged in storage

Li-ion cells stored at or below 2.5V trigger a BMS lockout that blocks normal charging. The U3 2018 4G charger will show no charging indicator when this happens. Connect the phone to a USB charger and leave it for 15–20 minutes without pressing the power button — the charge IC trickle-charges the cell from below the lockout threshold before the BMS re-enables full current flow. Once the cell recovers to approximately 3.0V, the phone will power on and charge normally.