Telstra Essential Plus 2018 Replacement Battery TLI019D7 3.8V 1900mAh

Telstra Essential Plus 2018 — 3.8V Li-ion Replacement Battery (TLI019D7)

This is a 3.8V, 1900mAh Li-ion cell for the Telstra Essential Plus 2018 smartphone. It replaces part number TLI019D7 when the original cell degrades and can no longer hold a usable charge. Capacity is 7.22Wh — matched to the original specification.

• Essential Plus 2018 fitment: The Essential Plus 2018 uses a removable cell with a fixed connector pinout tied to the TLI019D7 part number. The BMS on the phone's charge IC expects a cell within this voltage window — a mismatch triggers charge cutoff before the cell is full.
• Bench tested on actual hardware: We cycled this cell through a full discharge-charge sequence and monitored the BMS handshake with the phone's charge controller. The cell accepted charge current without triggering a protection cutoff, and the fuel gauge IC tracked state-of-charge across the full cycle.
• Fuel gauge recalibration on first use: After fitting this cell, disable fast charging for the first complete discharge-charge cycle. The phone's fuel gauge IC is still calibrated to the old cell's discharge curve. Running one full cycle at standard current lets the coulomb counter reset its reference points before high-current charging is applied to an uncalibrated cell.

Sudden shutdown at 20–30% on the Essential Plus 2018

This is the most common complaint after a cell swap. The phone's fuel gauge IC was calibrated to the old cell's internal resistance curve, so the percentage shown on screen no longer maps accurately to actual cell voltage. When the modem fires a data burst or the screen hits full brightness, the new cell's voltage drops faster than the IC expects — the protection circuit sees an undervoltage event and cuts power. One complete discharge to the auto-shutoff point followed by a full charge resets the coulomb counter against the new cell and clears the phantom shutdown.

Phone will not power on after sitting in storage with a flat battery

Li-ion cells that have discharged below approximately 2.5V in storage trigger a BMS lockout — the protection circuit blocks charge current to prevent damage to a deeply depleted cell. The phone will show nothing on screen and may not respond to the charger. Connect the phone to a wall adapter — not a USB port — and leave it for 20–30 minutes without pressing the power button. Most charge ICs apply a trickle pre-charge current that slowly brings the cell above the BMS re-enable threshold, after which normal charging resumes.