Assessment of the State-of-the-Art of electric vehicle charging stations: Classifications and design

The rapid growth of electric mobility is increasing the demand for resilient, interoperable, and grid-integrated Electric Vehicle Charging Stations (EVCSs). However, large-scale EV deployment introduces major technical challenges related to grid stability, charging coordination, renewable integration, interoperability, and infrastructure scalability, particularly in developing countries with weak distribution networks. This paper presents a critical review of state-of-the-art EVCS technologies, focusing on charging classifications, converter architectures, smart charging control strategies, communication standards, and renewable energy integration. The study comparatively evaluates AC/DC charging systems, wired and wireless charging methods, and centralized, decentralized, distributed, and hierarchical control architectures using key performance indicators including efficiency, scalability, grid impact, communication complexity, and deployment feasibility. In addition, major interoperability standards such as IEC 61851, ISO/IEC 15118, OCPP, and IEC 63110 are reviewed in the context of smart charging and Vehicle-to-Grid (V2G) applications. The paper further examines the integration of photovoltaic systems and Battery Energy Storage Systems (BESS) for sustainable EV charging under weak-grid conditions. Key findings indicate that hybrid PV–BESS-assisted EVCS architectures and intelligent charging coordination strategies can significantly improve grid flexibility, operational reliability, and energy sustainability. Finally, the paper identifies critical research gaps related to interoperability, cybersecurity, renewable intermittency, and real-world deployment in sub-Saharan Africa, providing future directions for scalable and context-aware EV charging infrastructure development.