BASE Lutea 2 Replacement Battery 3.7V 1100mAh Li-ion

BASE Lutea 2 — 3.7V Li-ion 1100mAh Replacement Battery

This is a 3.7V, 1100mAh lithium-ion cell for the BASE Lutea 2 smartphone. It replaces the original battery when the phone no longer holds charge or shuts down unexpectedly. Swap it in when the existing cell has degraded past usable capacity.

• Lutea 2 cell fit: The Lutea 2 uses a compact 84 x 34 x 4mm cell at 3.7V nominal. This replacement matches those physical and electrical parameters exactly — same connector position, same charge termination voltage the phone's charge IC expects at 4.2V.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the bench and confirmed the BMS communicates cleanly with the phone. The fuel gauge IC accepted the new cell without throwing a fault on the charge controller.
• First-cycle fuel gauge reset: After fitting this cell, run one full discharge down to automatic shutdown, then charge uninterrupted to 100% before normal use. This gives the Lutea 2's coulomb counter a clean reference curve for the new cell and prevents early percentage-reading drift.

Why the Lutea 2 reports wrong battery percentage after a cell swap

The Lutea 2 uses a fuel gauge IC that builds its capacity model from the discharge curve of the cell it learned on — typically the original factory cell. When you install a replacement, the IC still references that old curve. Until it recalibrates, it can report 40% remaining when the cell is actually at 15%. One full discharge-to-shutdown followed by a full uninterrupted charge corrects the reference. After that cycle, percentage readings stabilise.

Sudden shutdown at 20–30% on the Lutea 2 after battery replacement

This is a voltage cliff failure, not a capacity problem. Under load — modem transmitting, screen at full brightness — the cell voltage drops sharply below the 3.4V threshold the phone's protection circuit uses as its cutoff. A new cell with an uncalibrated fuel gauge makes this worse because the phone does not know real state-of-charge. If this occurs, run that first full discharge cycle. If shutdowns persist below 3.5V under load after two full cycles, the cell has a high internal resistance issue — check charge current is reaching at least 500mA during the charge phase.