LG KU950 Replacement Battery 3.7V 1000mAh Li-ion

LG KU950 — 3.7V Li-ion Replacement Battery

This is a 3.7V, 1000mAh Li-ion cell for the LG KU950 flip phone. It slots into the original battery compartment and connects to the same three-contact puck on the chassis. Voltage and capacity match the factory specification exactly.

• KU950 and KU-950 compatibility: Both model strings refer to the same hardware revision. The battery compartment, contact layout, and BMS handshake voltage are identical across both designations — no adapter or modification needed.
• Bench tested on actual hardware: We cycled this cell through full charge and discharge on a KU950 chassis. The BMS accepted the cell without triggering a protection cutoff, and the charge IC stepped through trickle, constant-current, and constant-voltage phases cleanly.
• Fuel gauge recalibration on first use: After fitting the new cell, run one complete discharge down to automatic shutoff, then charge uninterrupted to 100%. This gives the KU950's fuel gauge IC a clean reference curve for the new cell before it starts reporting percentage to the display.

Why the KU950 reports wrong battery percentage after a cell swap

The KU950 uses a simple fuel gauge IC that tracks charge state against a discharge curve learned from the previous cell. When a new cell goes in, the IC is still reading against the old, degraded curve — so it overshoots or undershoots the real state of charge. This causes the percentage bar to jump or plateau at odd levels. One full discharge-to-shutoff and uninterrupted recharge resets the reference. After that cycle, the readout tracks accurately against the new cell.

Sudden shutdown at 20–30% on the replacement cell

This happens when the fuel gauge IC has not yet recalibrated and the cell voltage drops below the BMS cutoff threshold — typically around 3.0V — before the display shows a low-battery warning. The modem draw during an active call accelerates the voltage drop faster than the IC expects. The fix is the same recalibration cycle: one full discharge to automatic shutoff, then a full charge to 100%. If shutdowns continue after two full cycles, check that the battery contacts on the chassis are clean and making firm contact with the cell.