About this replacement
LG KE600 / U400 — 3.7V Li-ion Replacement Battery (LGLI-ACHM)
This is a 3.7V, 850mAh Li-ion cell built to fit the LG KE600 and U400 mobile phones. It replaces OEM part LGLI-ACHM directly. Capacity figure is 850mAh (3.15Wh) as specified in the product data.
- KE600 and U400 compatibility: Both handsets share the same battery bay dimensions, connector pinout, and 3.7V nominal voltage rail — meaning one cell covers both models without modification to contacts or housing.
- Bench tested on actual hardware: We cycled the cell through charge and discharge on a KE600 chassis and monitored BMS handshake signals. The protection circuit responded correctly to end-of-charge and low-voltage cutoff thresholds across multiple cycles.
- Fuel gauge recalibration on first use: On first installation, run one complete discharge-to-charge cycle before enabling any fast-charge option. The fuel gauge IC on these handsets calibrates its coulomb counter against the new cell's discharge curve — skipping this step causes erratic percentage readings in the first week of use.
Why the KE600 reports wrong battery percentage after a cell swap
The KE600's fuel gauge IC stores a discharge curve from the original cell. When a new cell goes in, the IC has no reference data for how voltage maps to remaining capacity on that specific cell. It continues reading voltage and estimating percentage against the old curve, which no longer matches. The result is that the display shows 80% when the cell is near 60%, or drops suddenly. One full discharge-charge cycle forces the IC to rebuild its calibration table against the new cell's actual voltage profile. After that cycle, percentage accuracy returns to normal.
Sudden shutdown at 20–30% remaining on the replacement cell
This is a voltage cliff issue, not a capacity problem. Under the load of an active call or screen-on usage, the cell's terminal voltage drops faster than the fuel gauge predicts — crossing the BMS cutoff threshold while the display still shows charge remaining. It happens most often in the first few cycles on a new cell before the fuel gauge IC recalibrates. Run two full discharge-charge cycles without interruption. If shutdowns continue past that point, check that the battery contacts on the chassis are clean and making firm contact, since high contact resistance amplifies voltage sag at load.