LG P880 Optimus 4X HD Replacement Battery BL-53QH 3.7V

LG Optimus 4X HD / Optimus LTE II — 3.7V Li-ion Replacement Battery (BL-53QH)

This is a 3.7V 1800mAh Li-ion replacement cell for the LG P880 (Optimus 4X HD) and Optimus LTE II / LTE 2 series. It slots into the same battery bay as the original BL-53QH and uses the same three-contact connector layout. Capacity is 1800mAh — matching the stock specification across all listed fit models.

• P880 and Optimus LTE II platform fit: These models share the same battery bay dimensions, connector pinout, and BMS handshake protocol. One cell covers the full listed range without adapter or modification.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the P880 platform. The protection circuit triggered correctly at low-voltage cutoff, and charge termination fired at the expected 4.2V ceiling with no thermal anomalies noted.
• Fuel gauge recalibration on first install: After fitting this cell, run one complete discharge to automatic shutdown, then charge uninterrupted to 100% before normal use. The P880's fuel gauge IC was calibrated to your old cell's discharge curve — skipping this step causes the percentage readout to drift or jump for the first several cycles.

Why the P880 reports wrong battery percentage after a cell swap

The P880 uses a coulomb-counter-based fuel gauge IC that tracks charge state relative to the cell it learned on. When you fit a new cell, the IC still references the old discharge curve, so percentage readings drift — often showing 100% when the cell is partially charged, or dropping suddenly near the end. A single full discharge-to-shutdown followed by an uninterrupted charge to 4.2V forces the IC to recalibrate against the new cell. After one complete cycle, percentage accuracy normalises. No third-party app or reset is needed — the hardware corrects itself through the cycle.

Sudden shutdown at 20–30% remaining on the replacement cell

This happens when the modem, screen backlight, or GPS pulls a current spike the cell voltage cannot sustain — the terminal voltage drops below the protection circuit's cutoff threshold even though the fuel gauge still shows charge remaining. It is a voltage-sag issue, not a faulty cell. On a new cell that has not completed its first calibration cycle, the BMS cutoff appears earlier because the IC does not yet know the cell's true low-voltage knee. Complete one full discharge-charge cycle first. If shutdown still occurs below 3.2V under load after two full cycles, check that no background process is spiking draw during the affected percentage window.