Secure and privacy-preserving blockchain-based EV charging with mutual authentication and priority scheduling in V2G networks

The rapid adoption of electric vehicles (EVs) is increasing pressure on charging infrastructure, where secure communication, driver privacy, and charging-station congestion remain major challenges. This paper presents a blockchain-based charging framework that addresses these challenges in an integrated manner. The proposed framework enables Battery Electric Vehicles (BEVs), Charging Station Units (CSUs), Roadside Communication Units (RSCUs), and the Utility Data Centre (UDC) to register using pseudo-identities and authenticate each other through a lightweight mutual authentication scheme protecting driver identities. To improve charging efficiency, a Priority Charging Scheme (PCS) is combined with an optimization-based station-selection mechanism, enabling vehicles to select suitable charging stations rather than the nearest available station. Smart contracts are used to manage charging reservations, payments, and user feedback, providing a transparent and auditable record while keeping sensitive identities off-chain. Security analysis shows that the proposed framework is resistant to common attacks, including impersonation, replay, man-in-the-middle, Sybil, and double-spending attacks. Experimental results show that the proposed scheme reduces execution time by 77.9% and charging cost by 66.7%, while PCS increases fully charged BEVs by up to 58% compared with conventional scheduling.