HKC G801 Replacement Battery 3.7V 1500mAh Li-Polymer

HKC G801 / C880 / W1000 / G1000 — 3.7V Li-Polymer Replacement Battery

This is a 3.7V 1500mAh Li-Polymer cell for the HKC G801, C880, W1000, and G1000 smartphones. All four models share the same battery footprint, voltage rail, and connector. Capacity is 1500mAh (5.55Wh) — exactly as rated in the original specification.

• G801 / C880 / W1000 / G1000 platform: These four HKC models run the same battery management circuit and connector pinout. A single cell covers all four without wiring changes or BMS conflicts.
• Bench tested on actual hardware: We cycled this cell through charge and discharge under a controlled load. The BMS accepted the cell, protection thresholds tripped correctly at low voltage, and charge termination fired at the expected cutoff point.
• Fuel gauge recalibration on first cycle: On first use after installation, disable fast charging and run one full discharge-to-charge cycle. The fuel gauge IC in these HKC models calibrates its coulomb counter against the cell's discharge curve. Skipping this step causes the percentage readout to drift or report incorrectly for the first several cycles.

Sudden shutdown at 20–30% on the HKC G801 after a cell swap

This is a voltage cliff problem, not a capacity problem. The fuel gauge IC still holds calibration data from the old, degraded cell. When the new cell's discharge curve differs from that stored profile, the IC miscalculates remaining charge. Under a high-current draw — mobile data, screen-on, GPS active simultaneously — the cell voltage drops sharply below the shutdown threshold before the gauge reaches 0%. One full discharge-charge cycle with fast charging off forces the IC to relearn the curve against the actual cell. After that cycle, shutdowns at 20–30% should stop.

Phone warm near the battery during the first few charges after replacement

A new Li-Polymer cell has higher internal impedance than a broken-in cell. The charge IC pushes current into that higher impedance, which generates more heat in the first two to three cycles. This is normal and resolves as the cell's impedance drops with use. If the device stays warm beyond the third full charge cycle, check that the charge IC is not stuck in fast-charge mode against an uncalibrated fuel gauge — disabling fast charging for cycle four and checking the percentage stability will confirm whether the gauge has settled.