ISO 15118 is an international standard that defines a communication protocol for charging electric vehicles (EVs). It is part of the broader set of standards known as the Combined Charging System (CCS) and aims to enable seamless, secure, and efficient communication between EVs and charging infrastructure. Here are some key aspects of ISO 15118:

1. Plug & Charge (PnC): One of the most significant features of ISO 15118 is the "Plug & Charge" capability. This allows an EV to automatically authenticate and authorize charging when connected to a compatible charging station, eliminating the need for a physical card or smartphone app.

2. Bidirectional Charging (Vehicle-to-Grid or V2G): The standard supports bidirectional power flow, enabling EVs to not only charge from the grid but also supply power back to it. This is crucial for integrating EVs into smart grids and for providing ancillary services like grid stabilization.

3. Interoperability: ISO 15118 ensures that different EVs and charging stations can communicate effectively, regardless of manufacturer. This interoperability is essential for a seamless user experience across different regions and charging networks.

4. Secure Communication: The standard incorporates strong security mechanisms to protect the communication between the EV and the charging station. This includes measures to prevent unauthorized access and ensure data integrity and confidentiality.

5. Data Exchange: ISO 15118 facilitates the exchange of various types of data, including pricing information, charging schedules, and vehicle status. This helps optimize the charging process and can lead to more efficient energy use and cost savings for consumers.

6. Versions and Updates: The standard is continually evolving. The latest version, ISO 15118-20, expands on previous versions by adding more advanced features and capabilities.

7. Compatibility with Other Standards: ISO 15118 works in conjunction with other standards like IEC 61851 (which deals with EV conductive charging systems) and OCPP (Open Charge Point Protocol) to provide a comprehensive framework for EV charging.

Overall, ISO 15118 is a critical component in the development of a robust, user-friendly, and secure EV charging ecosystem, supporting the growth of electric mobility and the integration of renewable energy sources.