About this replacement
Motorola Moto Z Force — 3.85V Li-Polymer Replacement Battery (GV40 / SNN5968A)
This is a 3.85V, 2800mAh Li-Polymer replacement battery for the Motorola Moto Z Force, Moto Z Force TD-LTE, Moto Z Force Droid, and XT1650-02. It carries OEM part numbers GV40 and SNN5968A. Swap this cell when the original no longer holds charge or the phone shuts down unexpectedly under load.
- XT1650 platform fit: The Moto Z Force and its TD-LTE and Droid variants all share the same 3.85V battery bay, flex connector pinout, and BMS handshake — one cell covers the full XT1650 lineup.
- Bench tested on actual hardware: We ran this cell through charge-discharge cycles on the XT1650 platform. The BMS accepted full charge without tripping overcurrent protection, and the fuel gauge IC tracked state-of-charge accurately after the first complete cycle.
- First-cycle fuel gauge calibration: On first use after installation, disable fast charging and run one complete discharge-charge cycle at standard current. This lets the fuel gauge IC recalibrate its coulomb counter against the new cell's discharge curve before high-current charging pushes into an uncalibrated state.
Sudden shutdown at 20–30% on the Moto Z Force after a cell swap
The Moto Z Force's Snapdragon 820 and its modem draw sharp current spikes during LTE handoff and screen-on events. A new cell with a slightly different internal resistance profile can hit a voltage cliff under that load even when the fuel gauge still reads 20–30%. The BMS interprets the voltage drop below its cutoff threshold as an empty cell and shuts the phone down. Run one full discharge to 0% and charge to 100% without fast charging — this recalibrates the coulomb counter and eliminates false cutoffs above 3.2V under load.
OS reporting wrong battery percentage after replacement
Android's fuel gauge IC on the XT1650 stores a learned discharge curve from the old cell. After a swap, that stored curve no longer matches the new cell's voltage-to-capacity relationship, so the reported percentage drifts — often showing 100% for too long, then dropping fast. The fix is straightforward: drain the phone fully until it powers off, then charge uninterrupted to 100% in one session. After that single full cycle, the coulomb counter resets its reference points against the new cell and percentage reporting stabilises.