Flywheel energy storage system with functionally gradient nanocomposite rotor

Flywheel energy storage (FES) devices have been a popular method of energy storage because of their low maintenance requirements and ability to charge and release substantial amounts of energy in a short period of time. The amount of energy stored in an FES device mainly depends on the angular velocity of the rotor. The objective of the rotor design is to maximize the angular velocity while maintaining the structural integrity. This paper studies the hypothetical value of maximum energy storage for different rotor materials. The analysis of the von Mises stress suggests the possibility of designing a functionally gradient nanocomposite rotor that is stronger at the inner radius and weaker at the outer radius. With this design, the material cost will be lower and the integrity of the structure will not be compromised.