About this replacement
Motorola Moto G85 5G / Moto S50 Neo 5G — 3.91V Li-Polymer Replacement Battery (QE50)
This 3.91V, 4850mAh lithium-polymer cell replaces the original QE50 battery in the Motorola Moto G85 5G, Moto S50 Neo 5G, XT2427, and XT2427-1. It restores power to the processor, display, and 5G modem stack after the original cell degrades or fails to hold charge. Dimensions are 86.00 × 63.20 × 4.70mm — matching the original tray footprint.
- Moto G85 5G and S50 Neo 5G platform fit: Both the XT2427 series and the S50 Neo 5G share the same QE50 cell format, voltage rail, and BMS connector pinout — one cell covers both platforms without adapters or modifications.
- Bench tested on actual hardware: We ran this cell through full charge-discharge cycles on a Moto G85 5G unit. The BMS accepted the cell, fuel gauge IC initialised correctly, and the charge IC stepped through trickle, constant-current, and constant-voltage phases without error flags.
- Fuel gauge recalibration on first cycle: On first use after installation, disable fast charging and run one complete discharge-charge cycle at standard rate. This lets the fuel gauge IC map the new cell's discharge curve before high-current fast charging pushes current into an uncalibrated coulomb counter.
Sudden shutdown at 20–30% on the Moto G85 5G after a cell swap
This happens because the fuel gauge IC is still using the discharge curve from the old, degraded cell. The new cell has a steeper voltage cliff under 5G modem and display load — the phone reads 25% but the cell voltage has already dropped below the cutoff threshold. The fix is one full unconstrained discharge down to automatic shutdown, followed by a full uninterrupted charge. After that cycle, the coulomb counter recalibrates to the new cell's actual capacity curve.
USB-PD fast charge not triggering on the first cycle after replacement
On the first charge cycle, the phone's charge IC may default to standard 5W input while it validates the new cell's BMS response. This is normal — the handshake between the charge IC and the BMS on a fresh cell can take one full cycle to complete. Do not switch chargers or cables mid-cycle trying to force fast charge. After the first full charge completes, reconnect the TurboPower adapter and fast charge should negotiate correctly at that point.