ISO 15118

What is ISO 15118?

At its most basic, ISO 15118 is an international standard that defines the communications protocol between the charging station and the electric vehicle, whether using AC, DC, wireless, or pantograph charging. The “formal” name for ISO 15118 is “Road Vehicles – Vehicle to Grid Communication Interface.”

The protocol enables Plug & Charge, in which, after a one-time registration, the EV driver simply plugs the vehicle into the charge point. Then, using the ISO 15118 protocol, the EV identifies itself to the charging station, allowing for instant authorization to initiate charging. Additionally, ISO 15118 enables two-way communication between the vehicle and the charging station, supporting bidirectional charging such as vehicle-to-grid (V2G).

Here are some features of ISO 15118 and the use cases they enable:

Who created ISO 15118?

ISO 15118 was developed by a committee of experts from both the automotive and utility industries. It was a collaboration between the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC), two leading global standards groups.

What is the latest version of ISO 15118?

The most current version of the protocol is ISO 15118-20, which expands capabilities around security, bidirectional power transfer (V2G), and vehicle to charging station interoperability.

Why is ISO 15118 essential to accelerate EV adoption?

As EV adoption grows, charging infrastructure must become more secure, interoperable, and easier to use. ISO 15118 establishes a standardized communication framework between the vehicle and the charging station, allowing secure authentication and authorization, which enables Plug & Charge, as well as  smart energy management, and advanced grid integration. By reducing friction in the charging experience while supporting scalable infrastructure, ISO 15118 plays a foundational role in long-term EV market growth.

ISO 15118 key value

For EV charging network operators, ISO 15118 supports the transition from basic charging to intelligent, scalable energy ecosystems.

1. Scalable energy management – supports coordinated load management across sites and networked infrastructure, enabling capacity growth without grid upgrades
2. Grid participation – establishes the communication framework required for bidirectional energy programs and emerging grid services such as demand response, peak load balancing, and virtual power plant (VPP) participation.
3. Security – defines certificate-based authentication and encrypted communication between vehicles and charging infrastructure
4. Operational automation – removes the need for manual authentication through apps, RFID tokens, etc., to initiate charging sessions, improving reliability and lowering operational complexity at scale
5. Seamless charging experience – creates a predictable, standardized charging interaction across compliant vehicles and infrastructure, supporting broader EV adoption

By aligning with ISO 15118, operators strengthen interoperability, strengthen system security, and prepare their networks for long-term scalability.

What are the main components of ISO 15118?

There are multiple parts to ISO 15118, covering the protocols required to connect and secure the hardware, software, and communication layers, minimizing the complexities that occur behind the scenes to enable seamless and easy charging.

The main components of the ISO 15118 family include:

• general definitions and use cases (ISO 15118-1) – outlines terminology, architecture, and core charging scenarios
• application and network communication (ISO 15118-2 and -20) – defines how messages are structured and exchanged between the EV and charging infrastructure
• physical and data link layers (ISO 15118-3 and related parts) – specifies the wired and wireless communication requirements
• conformance testing (ISO 15118-4 and -5) – defines testing procedures to ensure interoperability and compliance

How is ISO 15118 different from OCPP?

ISO 15118 defines communication between the electric vehicle and the charging station. OCPP (Open Charge Point Protocol) defines communication between the charging station and the charge point management system. Together, these standards enable secure, interoperable communication across the full charging ecosystem.

Examples of ISO 15118 in practice

Across public networks and private fleets, ISO 15118 is applied to standardize how vehicles and charging infrastructure communicate.

1. Interoperable charging across networks: When a driver uses infrastructure operated by a different network, ISO 15118 enables standardized communication between the vehicle and the charging station. Authentication and session data are exchanged securely, supporting consistent charging behavior across hardware vendors and backend systems.
2. Managed fleet EV charging: At a managed fleet depot, vehicles connect to compatible chargers and exchange digital certificates using ISO 15118. The system verifies vehicle identity and charging permissions automatically, allowing sessions to begin without manual authorization steps. This reduces operational complexity and supports consistent policy enforcement across the fleet.
3. Dynamic charging rate adjustment at a public site: An EV connects to a networked charging station. Through ISO 15118 communication, the vehicle shares relevant charging parameters with the charger. The charging station relays this information to the backend system, which evaluates site capacity and grid conditions. Based on those constraints, the charging session is adjusted automatically to maintain optimal load balance without requiring driver input.

Driivz supports ISO 15118

Driivz’s EV Charging and Energy Management Platform supports ISO 15118, including Plug & Charge functionality, enabling automatic vehicle authentication and seamless session initiation. As a hardware-agnostic platform, Driivz uses secure, encrypted communication between vehicles and charging infrastructure while fostering interoperability across diverse charging networks. Combined with advanced smart EV charging and energy management capabilities, Driivz helps operators deploy scalable, secure charging networks and prepare for bidirectional charging use cases, including V2G, aligned with evolving ISO 15118 standards.