<p>A 14-degree-of-freedom mechanical model of the dual rotor flywheel battery under the influence of tilt angle was established based on the overall method and isolation method, and its differential equations were derived. The fourth-order Runge Kutta method in Matlab was used to solve and analyze the vibration characteristics of the flywheel rotor. The relationship curve was obtained between the maximum radial amplitude of the rotor and the vehicle wheelbase, flywheel inclination angle, road excitation amplitude, and frequency. The optimal solution for symmetrically installing a nonlinear energy sink (NES) at a distance from the vehicle's center of mass was determined by numerical analysis methods. The influence of various parameters of NES on the vehicle's flywheel system was analyzed, and three optimization objective functions were established to optimize linear damping. The experiment showed that the optimized design scheme of the nonlinear energy sink had a good vibration reduction effect. The research results contributed to understanding dual rotor flywheel battery system vibration characteristics and provided theoretical guidance for improving operational stability.</p>