About this replacement
Nextbook NX785QC8G / NX785QC16G — 3.8V Li-Polymer Replacement Battery (1ICP3/92/123)
This 3.8V, 4000mAh Li-Polymer cell replaces the original battery in the Nextbook NX785QC8G and NX785QC16G tablets. Both are 7–8 inch Android tablets used for reading, browsing, and media playback. The OEM part number is 1ICP3/92/123.
- NX785QC8G and NX785QC16G compatibility: Both models run the same 3.8V battery rail, use the same connector, and share the same BMS handshake protocol — that is why one cell fits both variants.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the NX785 platform. The BMS accepted charge negotiation without fault codes and held voltage within spec across the full discharge curve.
- Fuel gauge reset after installation: After fitting this battery, run one full discharge to automatic shutoff, then charge uninterrupted to 100%. This forces the fuel gauge IC to recalibrate against the new cell and clears the inaccurate percentage readings that typically appear after a swap.
Nextbook NX785QC8G shutting down at 15–25% remaining
This happens because the display backlight and active WiFi together draw enough current to create a sharp voltage sag at the cell terminals. When cell voltage dips below the BMS low-voltage threshold — even briefly — the tablet cuts power before the reported percentage reaches zero. The fuel gauge IC reads average voltage, not instantaneous voltage under load, so the shutdown looks premature on screen. Running one full recalibration cycle after installing the new cell tightens the gap between reported and actual charge state.
Android reporting wrong battery percentage after swap
The fuel gauge IC stores calibration data tied to the old cell's charge curve. After a battery replacement, the IC has no valid reference for the new cell, so percentage readings drift or jump. This is not a fault with the replacement battery — it is a calibration mismatch. Fix it by discharging the tablet fully to automatic shutoff, then charging in one uninterrupted session to 100% at which point the fuel gauge IC locks new calibration data to the installed cell.