Abstract: The invention provides a flywheel system with energy-absorbing housing. The system provides a novel liner and restraint ribs which serve to de-energize debris particles resulting from the catastrophic failure of a flywheel. Also provided are energy-absorbing housing systems comprising a rotatable liner, one or more restraint ribs, and a fluid film bearing to control and dissipate the energy from the failure of a rotating mass.

Abstract: The invention provides a flywheel system with energy-absorbing housing. The system provides a novel liner and restraint ribs which serve to de-energize debris particles resulting from the catastrophic failure of a flywheel. Also provided are energy-absorbing housing systems comprising a rotatable liner, one or more restraint ribs, and a fluid film bearing to control and dissipate the energy from the failure of a rotating mass.

Abstract: Flywheel battery systems having improved energy density are provided. Such systems preferably have an inner rotor mounted coaxially and substantially cylindrically within an outer containment rotor. The outer rotor counter-rotate relative to said inner rotor so as to manage the net gyroscopic force generated by the flywheel system. The outer rotor has a greater relative inertia as compared to said inner rotor and therefore can be rotated at a relatively lower rotational velocity to balance the gyroscopic forces generated by the rotation of the inner rotor. The relative rotational velocities of the inner and outer rotor are maintained by a combined mechanical and magnetic drive/suspension system.

Abstract: A flywheel includes a cross-ply composite central portion including a plurality of fiber-containing layers and a relatively thick rim portion of circumferentially wound fibers impregnated with a binder. The relatively thick rim portion surrounds the central portion and is of sufficient radial thickness such that the ratio of the outer radius of the central portion to the outer radius of the rim portion is equal to or less than 0.90. The rim and central or core portions are secured together by a relatively large interference fit of at least 0.001 inch per inch of the outer radius of the rim. Such interference fit substantially precludes failure of the flywheel by rim-core separation as would occur in similar flywheels having such relatively thick rims in the absence of the aforesaid large interference fit. The tangential modulus of elasticity of the rim-portion fibers is substantially greater than the corresponding modulus of the core-portion fibers.