ISO 15118 is an international communication standard that defines how electric vehicles and charging stations exchange data. ISO 15118 standard enables secure, automated identification between the vehicle, charger, and backend systems. ISO 15118 is the foundation for Plug and Charge, allowing EVs to start charging and handle payments automatically without RFID cards or apps.
The ISO 15118 communication protocol includes key features such as encrypted communication, digital certificates, and bi-directional power transfer. ISO 15118 supports smart charging, vehicle-to-grid (V2G) energy flow, and grid-responsive load balancing. ISO 15118 improves interoperability between different charger manufacturers and service providers.
ISO 15118 has several versions, including ISO 15118-2 for data exchange and ISO 15118-20 for advanced features like wireless charging. ISO 15118 adoption progresses slowly due to infrastructure costs, cybersecurity demands, and integration with older systems.
ISO 15118 complements OCPP and OCPI: OCPP connects chargers to backend systems, while OCPI enables roaming between operators. Together, ISO 15118, OCPP and OCPI create a unified ecosystem for interoperable EV charging.
Monta supports ISO 15118 by providing software that enables Plug and Charge, secure authentication, and efficient charging management across compatible chargers.
What is ISO 15118 standard?
ISO 15118 is an international EV charging communication protocol that defines how data is exchanged between electric vehicles and charging stations. ISO 15118 standard establishes a common language that allows both sides to identify, authenticate, and manage charging sessions securely and automatically.
The full name of the standard is ISO 15118 — Road vehicles: Vehicle-to-Grid Communication Interface. ISO 15118 was developed by the International Organization for Standardization (ISO) in collaboration with the International Electrotechnical Commission (IEC) to ensure consistent communication between EVs and charging infrastructure worldwide.
The main purpose of ISO 15118 is to enable safe, automated, and interoperable communication within the electric vehicle (EV) ecosystem. ISO 15118 defines how vehicles and chargers exchange technical and financial information, supporting functions such as Plug and Charge, smart charging, and vehicle-to-grid (V2G) energy flow.
ISO 15118 directly governs the communication layer between an EV and a charging station, allowing them to negotiate parameters like charging speed, power limits, and authentication data. ISO 15118 makes charging faster, safer, and more reliable across different brands and networks.
How does ISO 15118 enable communication between EVs and charge points?
ISO 15118 enables communication between electric vehicles (EVs) and charge points by defining a digital protocol that manages identification, authorization, and energy exchange. The ISO 15118 standard creates a secure data link that allows both sides to communicate automatically before and during charging.
Communication between the EV and the charge point, or EVSE (Electric Vehicle Supply Equipment), is established through Power Line Communication (PLC) based on the TCP/IP model. Data is transmitted through the same cable that delivers electricity, removing the need for additional hardware or internet connectivity at the charger.
Under ISO 15118, the EV and charger exchange data related to identification, charging power, pricing, grid signals, and energy status. Thanks to ISO 15118, EVs and charge points can exchange digital certificates for authentication, power flow control parameters, and billing information for Plug and Charge transactions.
The ISO 15118 communication framework ensures that both EV and charger can negotiate charging conditions, optimize energy flow, and maintain secure, encrypted communication throughout the session.
How does ISO 15118 enable plug and charge, and how does it work in practice?
ISO 15118 enables Plug and Charge by allowing automatic identification and payment when an electric vehicle connects to a compatible charger. The ISO 15118 standard removes the need for cards, apps, or manual authentication, making charging a seamless part of the connection process.
Plug and Charge works through a secure exchange of digital certificates stored in both the EV and the charging station. When the vehicle is plugged in, ISO 15118 establishes an encrypted communication channel that verifies the vehicle’s identity using certificate-based authentication and digital signatures.
Once the EV is authenticated, the charging session begins automatically, and billing information is sent to the service provider through the backend system. Plug and Charge ensures accurate and transparent transactions without user interaction.
For Plug and Charge to function, the EV, charge point, and backend platform must all support ISO 15118 and share valid digital certificates issued by trusted certificate authorities. The electric vehicle, the charger and the backend platform together create a secure, interoperable environment for automated EV charging.
What are the key features and benefits of ISO 15118?
ISO 15118 introduces a set of features that make EV charging secure, automated, and interoperable across networks.
The key features of ISO 15118 are listed below.
- Plug and Charge: enables automatic vehicle identification and payment without manual authentication.
- Secure communication: uses Transport Layer Security (TLS) and digital certificates for encryption and verification.
- Bidirectional charging (Vehicle-to-Grid, V2G): allows energy to flow between EVs and the grid.
- Smart charging: supports optimized charging based on pricing, demand, and energy source.
- Load and energy management: coordinates multiple charging sessions for grid stability.
- Interoperability: ensures compatibility across different EV models and networks.
- Scalability and modular design: adapts easily to new charging technologies and standards.
The key benefits of ISO 15118 are listed below.
- Enhanced user convenience: removes RFID cards, apps, or manual payments.
- Improved security: provides encrypted and authenticated communication.
- Streamlined billing and energy management: automates transactions and integrates with backend systems.
- Support for renewable integration: enables charging aligned with renewable energy supply.
- Future-proof design: supports smart grid and V2G development.
- Reduced operational complexity: simplifies interoperability for manufacturers and operators.
What are the different parts of ISO 15118?
The parts of ISO 15118 are ISO 15118-1, ISO 15118-2, ISO 15118-3, ISO 15118-4, ISO 15118-5, ISO 15118-6, ISO 15118-7, ISO 15118-8, ISO 15118-10, and ISO 15118-20. Each ISO 15118 standard document defines a specific part of the EV-to-charger communication process. The early versions (Parts 1–3) established the foundation for conductive charging and data exchange. Later parts (4–10) introduced conformance testing and wireless communication standards. ISO 15118-20 represents the latest evolution, adding support for bi-directional DC charging, advanced Plug and Charge, and smart energy management.
The table below shows an overview of the main differences between the ISO 15118 standard parts.
| ISO 15118 Part | Title / Focus Area | Description |
| ISO 15118-1 | General information and use-case definition | Defines concepts, communication architecture, and V2G use cases. |
| ISO 15118-2 | Network and application protocol requirements | Specifies data exchange rules and message formats for conductive charging. |
| ISO 15118-3 | Physical and data link layer requirements | Details Power Line Communication (PLC) between EV and charger. |
| ISO 15118-4 | Network and application conformance tests | Defines procedures to test compliance with ISO 15118-2. |
| ISO 15118-5 | Physical and data link conformance tests | Verifies correct implementation of PLC communication layers. |
| ISO 15118-6 | Use-case definition for wireless charging | Adapts ISO 15118-1 to wireless power transfer systems. |
| ISO 15118-7 | Network and application protocol for wireless charging | Specifies communication logic for wireless energy transfer. |
| ISO 15118-8 | Physical and data link requirements for wireless charging | Describes wireless communication between the vehicle and charging pad. |
| ISO 15118-10 | Conformance tests for wireless communication | Provides verification methods for wireless protocol compliance. |
| ISO 15118-20 | Second-generation communication protocol | Expands Plug and Charge, adds V2G support, and introduces improved cybersecurity. |
ISO 15118-1
ISO 15118-1 defines the general information, scope, and use-case framework for the ISO 15118 family of standards. The main purpose of ISO 15118-1 is to outline the communication architecture, terminology, and interaction scenarios between electric vehicles and charging stations. ISO 15118-1 establishes the foundation for how data exchange and energy transfer are managed within the entire ISO 15118 protocol.
ISO 15118-1 contributes to the overall communication framework by describing how an EV and an EVSE identify each other, negotiate charging parameters, and manage secure data flow. ISO 15118-1 serves as the conceptual layer that guides the technical specifications defined in later parts of the standard.
ISO 15118-1 was developed by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC) as part of the Joint Working Group ISO/TC 22/SC 31 and IEC/TC 69 and was first published in 2013 to address the lack of a unified communication framework for vehicle-to-grid (V2G) interaction and Plug and Charge functionality.
ISO 15118-1 precedes ISO 15118-2 and ISO 15118-3, providing the structural and logical foundation upon which data protocols and physical communication layers were later built. The development of ISO 15118-1 aimed to solve early interoperability challenges and define a consistent reference model for EV charging communication.
ISO 15118-2
ISO 15118-2 defines the network and application protocol requirements for communication between electric vehicles and charging stations. The main purpose of ISO 15118-2 is to specify how messages are structured, exchanged, and processed during conductive charging sessions. ISO 15118-2 ensures consistent data transfer for identification, authorization, and energy management between the EV, charger, and backend systems.
ISO 15118-2 contributes to the communication framework by defining the core data exchange process over TCP/IP using Power Line Communication (PLC). ISO 15118-2 establishes how parameters such as charging power, pricing, and Plug and Charge authentication are negotiated securely and automatically.
ISO 15118-2 was developed by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC) within the Joint Working Group ISO/TC 22/SC 31 and IEC/TC 69 and was first published in 2014 as a key technical specification following ISO 15118-1.
ISO 15118-2 builds directly on the conceptual foundation of ISO 15118-1 and operates together with ISO 15118-3, which defines the physical and data link layers. ISO 15118-2 addressed the need for a standardized, secure, and interoperable protocol to support Plug and Charge, smart charging, and early vehicle-to-grid (V2G) communication features.
ISO 15118-3
ISO 15118-3 defines the physical and data link layer requirements for communication between electric vehicles and charging stations. The main purpose of ISO 15118-3 is to describe how digital data is transmitted over the charging cable using Power Line Communication (PLC). ISO 15118-3 provides the technical foundation that enables the higher-level message exchange defined in ISO 15118-2.
ISO 15118-3 contributes to the overall communication framework by establishing the physical medium and signal transmission rules that ensure reliable and secure data flow between EVs and EVSEs. The main role of ISO 15118-3 is to define how the communication channel is initialized, maintained, and terminated during a charging session.
ISO 15118-3 was developed by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC) within the Joint Working Group ISO/TC 22/SC 31 and IEC/TC 69. ISO 15118-3 was first published in 2015 as part of the initial ISO 15118 series rollout.
ISO 15118-3 directly follows ISO 15118-2 and supports its application and network-level requirements and addressed the technical need for a stable and standardized communication link between EVs and chargers, solving early interoperability and signal reliability challenges in conductive charging systems.
ISO 15118-4
ISO 15118-4 defines the network and application layer conformance tests for the ISO 15118 communication protocol. The main purpose of ISO 15118-4 is to verify that the implementations of ISO 15118-2 comply with the defined message structures, communication rules, and data exchange procedures. The role of ISO 15118-4 is to ensure that systems built by different manufacturers can communicate reliably and securely.
ISO 15118-4 contributes to the overall communication framework by providing standardized testing procedures that validate interoperability between electric vehicles, charging stations, and backend systems. ISO 15118-4 confirms that network and application functions perform correctly under real-world conditions.
ISO 15118-4 was developed by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC) through the Joint Working Group ISO/TC 22/SC 31 and IEC/TC 69. ISO 15118-4 was first published in 2018 as a follow-up to ISO 15118-2 and ISO 15118-3.
ISO 15118-4 builds directly on ISO 15118-2, using its network and application definitions as a reference for testing. ISO 15118-4 addressed the need for a uniform validation method to ensure compatibility, reduce integration issues, and improve reliability in the expanding EV charging market.
ISO 15118-5
ISO 15118-5 defines the physical and data link layer conformance tests for the ISO 15118 communication protocol. The main purpose of ISO 15118-5 is to verify that the Power Line Communication (PLC) layer, as described in ISO 15118-3, operates correctly and consistently across different hardware and software implementations. ISO 15118-3 ensures reliable data transmission between electric vehicles and charging stations during charging sessions.
ISO 15118-5 contributes to the overall communication framework by establishing standardized procedures to test the performance and stability of the physical communication layer. ISO 15118-5 confirms that the signal exchange, synchronization, and error-handling mechanisms function as specified.
ISO 15118-5 was developed by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC) under the Joint Working Group ISO/TC 22/SC 31 and IEC/TC 69 in 2018 as a complement to ISO 15118-4. ISO 15118-5 completes the first set of conformance testing documents within the ISO 15118 family.
ISO 15118-5 builds on ISO 15118-3 by applying its technical definitions to a testing framework and addresses the need for a standardized validation process to ensure interoperability, communication reliability, and compliance across different EV and charger manufacturers.
ISO 15118-6
ISO 15118-6 defines the general information and use-case framework for wireless communication between electric vehicles and charging stations. The main purpose of ISO 15118-6 is to extend the ISO 15118 standard to support wireless power transfer (WPT) systems, outlining how communication and energy transfer occur without physical cables.
ISO 15118-6 contributes to the overall communication framework by adapting the concepts from ISO 15118-1 to the wireless charging environment. The role of ISO 15118-6 is to specify how an EV and EVSE establish secure, automated communication to manage identification, authorization, and charging control in inductive systems.
ISO 15118-6 was developed by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC) through the Joint Working Group ISO/TC 22/SC 31 and IEC/TC 69. ISO 15118-6 was published in 2020 as the first part of the ISO 15118 wireless communication series.
ISO 15118-6 connects conceptually to ISO 15118-7 and ISO 15118-8, which define the network, application, and physical layers for wireless data exchange. The creation of ISO 15118-6 addressed the growing need for a standardized approach to wireless EV charging communication, ensuring interoperability and safety across different wireless charging technologies.
ISO 15118-7
ISO 15118-7 defines the network and application protocol requirements for wireless communication between electric vehicles and charging stations. The main purpose of ISO 15118-7 is to specify how data is exchanged in wireless power transfer (WPT) systems, enabling secure, automated control of wireless charging sessions.
ISO 15118-7 contributes to the overall communication framework by translating the wired communication principles of ISO 15118-2 into a wireless environment. ISO 15118-7 defines message formats, authentication procedures, and data handling methods that ensure safe and efficient operation during wireless charging.
ISO 15118-7 was developed by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC) within the Joint Working Group ISO/TC 22/SC 31 and IEC/TC 69. ISO 15118-7 was published in 2020 as part of the ISO 15118 wireless communication series.
ISO 15118-7 builds on ISO 15118-6, which provides the general framework for wireless use cases, and aligns with ISO 15118-8, which defines the physical and data link layers. The creation of ISO 15118-7 addressed the need for a unified communication protocol that ensures interoperability, security, and efficiency in wireless EV charging.
ISO 15118-8
ISO 15118-8 defines the physical and data link layer requirements for wireless communication between electric vehicles and charging stations. The main purpose of ISO 15118-8 is to specify how data is transmitted during wireless power transfer (WPT), ensuring stable and secure communication between the EV and EVSE.
ISO 15118-8 contributes to the overall communication framework by establishing how the wireless signal is modulated, synchronized, and maintained throughout the charging process. The role of ISO 15118-8 is to provide the technical basis for reliable data exchange in inductive charging systems, complementing the higher-level protocols defined in ISO 15118-7.
ISO 15118-8 was developed by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC) within the Joint Working Group ISO/TC 22/SC 31 and IEC/TC 69. ISO 15118-8 was published in 2020 as part of the wireless communication expansion of the ISO 15118 standard series.
ISO 15118-8 directly supports ISO 15118-7 by defining the underlying communication medium for wireless data transmission. The creation of ISO 15118-8 addressed the need for standardized signal protocols to ensure interoperability, electromagnetic compatibility, and communication reliability in wireless EV charging environments.
ISO 15118-10
ISO 15118-10 defines the conformance tests for wireless communication within the ISO 15118 family. The main purpose of ISO 15118-10 is to verify that implementations of the wireless network and application protocols, as described in ISO 15118-7 and ISO 15118-8, function correctly and consistently. ISO 15118-10 ensures that wireless charging systems from different manufacturers can communicate reliably and securely.
ISO 15118-10 contributes to the overall communication framework by providing standardized testing procedures to evaluate the performance and interoperability of wireless EV charging communication layers. The role of ISO 15118-10 is to validate that the system meets the required specifications for authentication, data transfer, and connection stability.
ISO 15118-10 was developed by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC) through the Joint Working Group ISO/TC 22/SC 31 and IEC/TC 69. ISO 15118-10 was published in 2021 as part of the ISO 15118 series to complete the wireless communication testing suite.
ISO 15118-10 builds upon ISO 15118-7 and ISO 15118-8 by translating their functional definitions into measurable test cases. The creation of ISO 15118-10 addressed the need for standardized validation methods that ensure interoperability, compliance, and safety in wireless EV charging systems.
ISO 15118-20
ISO 15118-20 defines the second generation of the vehicle-to-grid (V2G) communication interface within the ISO 15118 family. The main purpose of ISO 15118-20 is to expand the capabilities of earlier parts by introducing advanced features such as bidirectional DC charging, improved Plug and Charge functionality, and enhanced cybersecurity. ISO 15118-20 provides a unified framework that supports both conductive and wireless charging.
ISO 15118-20 contributes to the overall communication framework by integrating smart energy management, faster message handling, and flexible power negotiation between electric vehicles, charging stations, and energy management systems. The role of ISO 15118-20 is to enable large-scale interoperability and supports the transition toward grid-integrated charging infrastructure.
ISO 15118-20 was developed by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC) within the Joint Working Group ISO/TC 22/SC 31 and IEC/TC 69. ISO 15118-20 was officially published in 2022, marking a major update to the ISO 15118 standard series.
ISO 15118-20 builds on ISO 15118-2 and ISO 15118-3 while extending its scope to cover both AC and DC bi-directional charging, improved data models, and faster communication sequences. The creation of ISO 15118-20 addressed the growing need for a scalable, secure, and future-ready protocol capable of supporting smart grids, renewable integration, and advanced Plug and Charge services. Recent ISO 15118-20 news highlights its role in enabling interoperability between next-generation EVs and chargers as manufacturers move toward large-scale adoption of Plug and Charge and V2G capabilities.
Is ISO 15118 mandatory?
No, ISO 15118 is not mandatory for all electric vehicles and charging stations. The ISO 15118 standard is widely recognized but not legally required on a global scale. The ISO 15118 adoption depends on regional regulations, industry initiatives, and manufacturer preferences. Many charging networks and EV makers implement ISO 15118 voluntarily to enable secure communication, Plug and Charge functionality, and smart charging features.
In Europe, ISO 15118 is being integrated into new infrastructure rules to promote consistent communication between vehicles and chargers. While not yet universal, the European Union encourages ISO 15118 compliance through policy frameworks that push toward interoperability and automation in public charging.
In North America, the ISO 15118 standard remains voluntary but is gaining traction through government-supported charging programs that recommend ISO 15118 for Plug and Charge compatibility. Industry stakeholders adopt ISO 15118 to prepare for future requirements and to improve user convenience and payment automation.
In Asia, ISO 15118 adoption varies across regions. Japan, South Korea, and China support ISO 15118 principles in their national EV communication standards, focusing on interoperability and secure data exchange. Across all regions, ISO 15118 complements other standards such as IEC 61851, ISO 17409, and OCPP, ensuring a unified approach to EV charging communication and compliance.
Does ISO 15118 support AC, DC, or both charging types?
Yes, ISO 15118 supports both AC and DC charging types. The ISO 15118 standard was designed to enable secure communication and energy management across all major charging methods used in electric vehicles. ISO 15118 ensures that identification, authorization, and charging control work consistently, regardless of whether the vehicle charges through alternating current or direct current.
Support for AC charging is defined mainly in ISO 15118-2, which establishes the data exchange protocols for conductive charging. DC charging is covered under the same part but expanded further in ISO 15118-20, which introduces advanced capabilities such as bidirectional energy flow for vehicle-to-grid operation.
Communication under ISO 15118 differs slightly between AC and DC modes. In AC charging, the exchange focuses on authentication, session setup, and energy transfer parameters, while in DC charging, ISO 15118 includes additional data for power negotiation, safety monitoring, and dynamic load control.
By supporting both AC and DC charging, ISO 15118 creates a unified communication framework that simplifies implementation for manufacturers and ensures interoperability across a wide range of charging infrastructure.
What challenges come with ISO 15118 adoption?
The main challenges that come with ISO 15118 adoption are listed below.
- High implementation cost: Significant investment is required for software updates, hardware upgrades, and backend system integration.
- Complex certificate management: Managing Public Key Infrastructure (PKI) for secure Plug and Charge authentication is technically demanding and resource-intensive.
- Limited interoperability: Not all electric vehicles, chargers, or networks support the same ISO 15118 versions, leading to compatibility issues.
- Fragmented ecosystem: Regional regulations and varying levels of technological maturity slow down consistent global adoption.
- Testing and certification gaps: The absence of fully standardized global certification processes makes compliance verification difficult.
- Evolving standards: The shift from ISO 15118-2 to ISO 15118-20 introduces compatibility and update challenges for existing systems.
- Backend integration complexity: Maintaining secure, real-time communication between EVs, chargers, and backend systems such as CPO and MSP platforms requires advanced technical coordination.
What is the difference between ISO 15118, OCPP, and OCPI?
The difference between ISO 15118, OCPP, and OCPI is that they serve different but complementary functions in the EV charging ecosystem. ISO 15118 manages direct communication between the electric vehicle and the charging station, while OCPP connects the charger to the backend system operated by a charge point operator. OCPI, in turn, enables roaming and data exchange between different service providers and networks.
ISO 15118, OCPP, and OCPI work together to create a complete communication chain. ISO 15118 handles secure data transfer, Plug and Charge authentication, and energy management at the vehicle level. OCPP focuses on charger monitoring, control, and maintenance through cloud-based management platforms. OCPI enables interoperability between networks, allowing users to charge across different operators using a single account or app.
ISO 15118 does not replace OCPP or OCPI. Instead, ISO 15118 complements OCPP and OCPI by covering the layer of communication that occurs before the charger connects to backend systems. Together, ISO 15118, OCPP and OCPI, enable a unified, interoperable EV charging environment that supports automation, transparency, and scalability.
How can companies achieve ISO 15118 compliance?
Companies can achieve ISO 15118 compliance by following the steps below.
- 1. Understand the standard and scope: Review the relevant ISO 15118 parts, such as ISO 15118-2, ISO 15118-3, and ISO 15118-20, to identify which requirements apply to hardware, software, and backend operations.
- 2. Assess existing systems: Conduct a gap analysis of current EVs, chargers, and backend platforms to determine what updates are needed to meet ISO 15118 specifications.
- 3. Implement communication protocols: Integrate Power Line Communication (PLC) for data transfer, Transport Layer Security (TLS) for encryption, and digital certificate handling for authentication.
- 4. Develop Plug and Charge functionality: Enable automatic identification and billing features according to ISO 15118-2 or ISO 15118-20 requirements.
- 5. Integrate Public Key Infrastructure (PKI): Work with trusted certificate authorities to issue and manage digital certificates for secure Plug and Charge communication.
- 6. Perform conformance and interoperability testing: Test communication between EVs, charging stations, and backend systems to ensure reliability and standard compliance.
- 7. Obtain certification: Collaborate with recognized testing bodies or ISO-accredited laboratories, such as CharIN, to validate and certify compliance.
- 8. Maintain and update compliance: Renew certificates periodically, update firmware, and align systems with the latest ISO 15118 revisions and security requirements.
Does Monta offer ISO 15118-compliant EV charging software?
Yes, Monta offers ISO 15118-compliant EV charging software that supports Plug and Charge, secure communication, and interoperability across compatible chargers. The Monta platform enables automatic vehicle authentication and payment processing based on ISO 15118 standards, ensuring a seamless and secure charging experience for drivers.
Monta integrates ISO 15118 features within its EV charging management ecosystem through encrypted data transfer, digital certificate handling, and backend coordination between eMobility Service Providers and Charge Point Operators. Monta allows network operators to manage ISO 15118-enabled chargers and transactions through a unified interface.
By supporting ISO 15118, Monta helps charging networks and businesses prepare for future interoperability requirements, streamline Plug and Charge deployment, and enhance user convenience while maintaining strong data security and operational efficiency.