This paper reviews the role of electric vehicles (EVs) in enhancing grid stability and flexibility through bidirectional charging and Vehicle-to-Everything (V2X) applications. It highlights the importance of EV batteries in supplying flexible demand capacity and providing demand response benefits to the power grid. The study examines various V2X applications in North America, their effects on battery longevity, and the impact of EV charging patterns. Advanced aging-aware optimization algorithms are introduced to manage bidirectional charging, aiming to extend battery life while ensuring efficient grid operation. The paper also discusses the challenges and opportunities presented by EVs in the context of an increasingly renewable energy landscape, emphasizing the need for robust communication networks and distributed energy resources to support virtual power plants (VPPs). The review concludes with a summary of key takeaways and recommendations for future research and real-world implementation.This paper reviews the role of electric vehicles (EVs) in enhancing grid stability and flexibility through bidirectional charging and Vehicle-to-Everything (V2X) applications. It highlights the importance of EV batteries in supplying flexible demand capacity and providing demand response benefits to the power grid. The study examines various V2X applications in North America, their effects on battery longevity, and the impact of EV charging patterns. Advanced aging-aware optimization algorithms are introduced to manage bidirectional charging, aiming to extend battery life while ensuring efficient grid operation. The paper also discusses the challenges and opportunities presented by EVs in the context of an increasingly renewable energy landscape, emphasizing the need for robust communication networks and distributed energy resources to support virtual power plants (VPPs). The review concludes with a summary of key takeaways and recommendations for future research and real-world implementation.