LG EG880 Replacement Battery 3.7V 1000mAh Li-ion

LG EG880 / G5400 / G5410 — 3.7V Li-ion Replacement Battery

This 3.7V, 1000mAh lithium-ion cell replaces the original battery in the LG EG880, G5400, and G5410 smartphones. It restores power to calls, messaging, and apps when the factory cell has degraded or stopped holding a charge. Voltage and capacity match the original spec exactly.

• EG880, G5400, and G5410 compatibility: These three models share the same 3.7V battery bay, connector pinout, and charge management circuit. One cell covers all three without modification.
• Bench tested on actual hardware: We cycled this cell through a full charge and discharge on bench equipment, confirming BMS communication with the charge IC and verifying cutoff voltages at both ends of the curve.
• Fuel gauge recalibration on first use: On first use after installation, disable fast charging if available and run one complete discharge-to-charge cycle. This lets the fuel gauge IC map the new cell's discharge curve before it begins reporting percentage to the OS.

Why the LG EG880 reports wrong battery percentage after a cell swap

The EG880's fuel gauge IC stores a learned discharge curve for the original cell. When a new cell goes in, that stored curve no longer matches the actual voltage-to-capacity relationship of the replacement. The OS reads percentage from the fuel gauge, not from the cell directly, so the number on screen can be off by 10–20% until recalibration happens. One full discharge down to auto-shutdown followed by a full charge resets the coulomb counter and brings the percentage readout back in line.

Sudden shutdown at 20–30% on the replacement cell

This happens when the cell voltage drops below the modem or screen load threshold faster than the fuel gauge expects — a voltage cliff the old calibration curve didn't account for. The BMS trips the output before the displayed percentage reaches zero, because the actual cell voltage has already fallen below 3.4V under load. It is not a fault with the cell. Run two full discharge-charge cycles without heavy background tasks and the cutoff point will stabilise. If it persists past two cycles, check that the battery connector is fully seated — a loose pin adds resistance and accelerates voltage sag under load.