BL-53YH LG G3 Replacement Battery 3.8V 6000mAh

LG G3 / D855 Series — 3.8V Li-ion Replacement Battery (BL-53YH)

This is a 3.8V, 6000mAh Li-ion replacement battery for the LG G3 smartphone. It fits the D855, D855 LTE, D855K, and related G3 variants using OEM part number BL-53YH. Swap it in when the original cell has degraded and the phone no longer holds a usable charge.

• G3 and D855 series fit: All listed G3 variants share the same 3.8V cell footprint, BL-53YH connector pinout, and BMS handshake protocol. The replacement cell matches that specification so the charge IC accepts it without error flags.
• Bench tested on actual hardware: We ran this cell through full charge and discharge cycles on the G3 platform. The BMS accepted charge current without dropping into protection mode, and the fuel gauge IC tracked state-of-charge without hard cutoffs or error codes.
• First-cycle fuel gauge reset: On first use after installation, disable fast charging and run one complete discharge-to-charge cycle before re-enabling it. This lets the fuel gauge IC build a fresh discharge curve against the new cell before high-current charging runs against an uncalibrated coulomb counter.

Why the G3 reports wrong battery percentage after a cell swap

The G3 uses a coulomb counter inside the fuel gauge IC to estimate state-of-charge. That counter was calibrated against the discharge curve of the original cell. A new cell — especially one with higher capacity — has a different curve, so the IC maps percentage to voltage incorrectly at first. The phone may show 50% and drop immediately, or read 100% before the cell is actually full. One full discharge down to automatic shutdown, followed by a full charge to 4.2V, forces the IC to remap against the new cell's actual curve.

Sudden shutdown at 20–30% on the replacement cell

This is a voltage cliff problem, not a capacity problem. Under combined load — LTE modem active, screen at full brightness — the cell's internal resistance causes a voltage sag that trips the BMS low-voltage cutoff before the fuel gauge reaches 0%. On an uncalibrated fuel gauge IC, the displayed percentage at the moment of cutoff can look anywhere from 15% to 35%. Run one full calibration cycle first. If shutdowns persist after calibration, confirm resting cell voltage is sitting above 3.7V after a full charge — anything lower suggests a cell defect.