LiPo batteries are the most maintenance-sensitive component in an FPV build. Misuse kills them fast or causes fires. Cell Voltage State Voltage per cell Fully charged 4.20 V Nominal 3.70 V Storage 3.80–3.85 V Low cutoff 3.50 V Dead / damaged < 3.30 V Never discharge below 3.5 V per cell under load. Set your FC …