Open Charge Point Protocol migration from 1.6 to 2.0.1

Being an eMobility leader in various projects across multiple startups, Piotr was responsible for OCPI and OCPP integration as well as EMP and CPO platforms development. With extensive expertise in the open standards field and eMobility tech solutions, he is leading teams of experienced developers and contributing with invaluable knowledge and experience.

Piotr Majcher

Keeping IT systems up-to-date, even with basic tasks like dependencies or newly coming company-wide best practices is challenging. Even if all components are maintained in-house, it’s time-consuming to keep all areas updated. This applies also to keeping up-to-date external protocols our system uses. Whether we are integrated with Stripe over HTTP API, or with thousands of charging stations over OCPP, it’s good to know what the latest API version introduces. All this in order to examine if there are new opportunities upfront our business that can be supported by the newest version of the protocol we use. Or maybe our market requires covering long-waited, flow enabling updates. Let’s dive deeper into the new features introduced in OCPP 2.0.1 to see if it’s worth spending time upgrading your CPO platform.

OCPP 2.0.1 introduced business-oriented features but also technical improvements like device management or security. Those aspects are likewise very important, but this article gathers the latest OCPP updates focusing on the business angle.

More sophisticated support for smart charging is OCA’s (Open Charge Alliance) answer for a growing interest in this area. Energy cost fluctuates during the day. Also, the amount of energy available on different levels (charging station, building/parking, grid) changes according to the current consumption, production, and network capabilities.

Having that fact in mind we can use it to plan the charging process, buy cheaper energy for the end-user, and not overload the network. We need to know when energy is cheaper or the network load is too high. It’s out of the scope of OCPP, but once we have such information, we should inform the charging station how to apply it to finally reduce the cost of charging and limit network load.

OCPP 1.6 already supports smart charging. What is new, OCPP 2.0.1 is being open for new types of input having an impact on the charging process. Let’s start from a quick overview of OCPP 1.6’s support for smart charging and then move to things that are new in version 2.0.1.

Whole smart charging is based on charging profiles. A single profile describes time intervals with power/current limits, for instance, a profile can define that between 0:00 and 10:00 we can charge using 5kW, and between 10:00 and 0:00 maximum energy is limited to 2kW.

Profiles can be stacked and merged in order to build complex profiles. There are three types of charging profiles:

ChargePointMaxProfile - profile of whole charge point

TxDefaultProfile - default profile for a transaction (can be for whole charge point or for specific connector)

TxProfile - profile for a single transaction, deleted once a transaction is finished.

The second essential concept is a type of smart charging. There are three types of smart charging setup supported in version 1.6:

From a technical perspective, everything is covered by three OCPP API operations:

As it was mentioned earlier, 2.0.1 is open to new sources of information driving smart charging. Since now we can consume information from:

electric vehicles connected to charge point (through the ISO 15118)

Imagine a situation where there are some external indicators saying the energy our charge points transfer to EVs has to be limited. We can handle that on the CPO side, consuming the information and preparing an adequate charging profile being sent to the charging station over OCPP. But the 2.0.1 version supports direct integration between charge points and EMS. An extreme example of such integration can be a hospital with a lot of critical health-related systems consuming energy and with parking having charge points. It’s obvious that charging cars is less important than keeping the core hospital’s infrastructure running. This is an example in case of a bigger load, the energy management system should limit energy flowing to the charging stations. It can be done directly between the EMS and charging stations outside the OCPP. But such an approach introduces a problem. The CPO platform can be lost because the charging station behaves not the way it was requested by the system. OCPP 2.0.1 solves this problem by introducing a notification mechanism that informs CSMS (Charging Station Management System) about some external limitations. There are many cases that can be solved by support for direct smart charging inputs from an energy management system:

integration with Building Energy Management System

integration with Home Energy Management System

From a technical perspective, a new charging profile type (ChargingStationExternal) has been introduced. External signals changing the charging profiles should be stored as a charging profile of this type. Once an external charging profile has been added, the charging station has to notify CSMS and it does it using the new message - NotifyChargingLimitRequest.

The issue of support for ISO 15118 will be covered in the next paragraph, now let’s focus on the parts of ISO 15118 related to smart charging. Smart charging is nothing more than gathering information about the state of the network (including prices, load, etc.), processing the data, and steering the charging process. Standard ISO 15118 introduces another one source of information that can be processed in order to plan charging processes effectively. The source of information is an EV. One of the most important pieces of information when planning a charging process is the amount of energy the car wants to consume. There are many options to provide such information to the CSMS:

user can enter requested energy using a mobile app (delivered by the eMSP) and through the backend-to-backend integration send it to the CPO’s CSMS,

the charging station may send this data directly to the CSMS using a custom API

We could even use a new measurand introduced in OCPP 1.6 called SoC (State of charge of charging the vehicle in percentage). All those approaches have significant drawbacks. They assume the user's manual action, using a custom API or doing some approximations (when translating percent of battery already charged to the energy to be consumed without knowing the capacity of the battery). None of those solutions is good enough to become a standard. But ISO 15118 together with OCPP 2.0.1 covers this part of smart charging. ISO 15118 as a standard describing communication between an electric vehicle and a charging station specifies what type of information can be exchanged between those two parties. EV sends:

energy request (target, minimum and maximum)

charging parameters (current, power, and voltage)

discharging parameters (current and power)

Once the data is sent to the EVSE, it can be translated to the OCPP message and sent to CSMS which can use this input to prepare the charging schedule and send it back to the charging station (taking into account other inputs like price info, network load from DSO, etc.).

OCPP 2.0.1 introduces the message NotifyEVChargingNeedsRequest to share ISO 15118 based information with CSMS. It has four parameters describing charging details sent by EV:

Once CSMS prepares a charging profile for the current transaction, it sends it using SetChargingProfileRequest OCPP message. EVSE is proxying the information to the EV and as a last step, EVSE can notify CSMS about the charging schedule calculated by the EV using the NotifyEVChargingScheduleRequest OCPP message.

What is also worth mentioning OCPP 2.0.1 introduced ISO 15118 based renegotiation of the charging schedule. Renegotiation can be triggered by both sides - EV and CSMS. It’s useful in order to quickly react to the latest changes in the grid, no matter if it’s to reduce costs or unstress the network.

Very often the eMobility world is compared to the petrol industry. One of the most frequently compared areas is the transfer of energy from the station to the car. It’s said that we still have to wait years to bring the same user experience for the eMobility users as gasoline-based car users have today because of the time needed to charge the car. There is one improvement that has never been available for classic cars, but some charging stations and electric cars already have it. It’s Plug & Charge. In short, it’s a technology that allows users to start charging sessions without manual authorization. A user just needs to plug in the cable and without scanning the RFID token or using a mobile application car starts to drain energy from the station. Once charging is done, users can be automatically billed, also without entering payment details anywhere. Everything thanks to the PKI based solution introduced in the ISO 15118 and also covered by the OCPP 2.0.1.

Plug & Charge is built on a trust that is guaranteed by the Public Key Infrastructure. The most interesting part of it is how it replaces the need for human intervention when doing the authorization. The EV has the contract certificate stored (X.509 certificate). The certificate associates the end-user with the public key. Because the certificate is issued by a trusted Certificate Authority, the charging station is able to check it, and if it’s valid, the charging station believes that the user presented in the certificate is not fake. User is identified by the ID called E-Mobility Account Identifier (eMAID) stored in the contract certificate. eMAID is also known to the eMSP for billing purposes. Thanks to that, eMSP knows which user has to be charged for the transaction started automatically just by plugging the cable.

Two main parts of OCPP cooperating with ISO 15118 in order to provide Plug & Charge are:

Whole ISO 15118 is built upon Public Key Infrastructure. That’s why the separate component managing certificates has been introduced in order to open OCPP for integration with EVSE supporting ISO 15118. There is a set of OCPP messages including:

that are designed to manage certificates related to ISO 15118.

The second part of OCPP allowing to implement Plug & Charge is Authorization flow. AuthorizeRequest message contains (among other fields) information about the token used for authorization. This is a message used to send RFID token or a Central token in a remote transaction. There are multiple types of tokens supported in OCPP version 2.0.1 (more about it in the next paragraph), but one of them is called eMAID. eMAID is sent together with the data allowing to verify contract certificate (certificate and iso15118CertificateHashData).

OCPP 1.6 and previous versions were designed to support RFID-based authorization. Version 2.0.1 introduced a set of new authorization mechanisms, among them:

Central - used in for example in remote transactions

KeyCode - for authorization using PIN-code

It opens new possibilities for the development of user-friendly interfaces that may make charging easier and more accessible for the end-users.

OCPP 2.0.1 introduces significant changes that bring new opportunities for the whole eMobility world. In order to develop an efficient smart charging system or introduce Plug & Charge, we have to involve many parties, to mention only well-known ones like CPOs, eMSPs, and OEMs. The connection between the charging station and the backend system (CSMS) is a piece of a puzzle - linked with an upgrade of OCPP to the latest version. The decision has to be made wisely because it has many consequences, however, the features OCPP 2.0.1 provides can give CPO business a notable boost.

OCPP 2.0.1 introduced business-oriented features but also technical improvements.

OCPP migration

Learn how OCPP enables interoperability in EV charging.

: the backbone of any thriving EV charging network.

Without it, we'd be looking at a patchwork of systems struggling to talk to each other. And that's not the kind of future anyone wants to plug into.

That's where open standards come in. Designed to eliminate silos and future-proof infrastructure, they're essential for scaling EV charging networks smartly and sustainably. Among them, the 

 stands out as the go-to framework for enabling communication between charging stations and backend systems.

In this article, we'll break down OCPP's role in the eMobility ecosystem and unpack the differences between its key versions: 

, so you can better understand where the industry's headed and what it means for your EV charging business or tech stack.

 is an open-source communication standard that enables electric vehicle (EV) charging stations to interact seamlessly with backend systems, such as Charging Station Management Systems (CSMS). It connects charging hardware to software platforms, regardless of the manufacturer.

Developed by the Open Charge Alliance (OCA), OCPP ensures interoperability across networks, making it easier for Charging Point Operators (CPOs) to manage stations, process billing, enable remote diagnostics, and scale their EV charging infrastructure.

, and an open standard, meaning anyone can develop applications that use it. However, it is not a mandatory industry requirement; while the OCA highly recommends its use, EVSE manufacturers are not obligated to produce OCPP-compliant hardware.

In terms of its role in the EV charging ecosystem, understanding OCPP's placement is crucial. OCPP acts as the communication syntax connecting the Charging Station Management System (CSMS) used by CPOs to control their networks with the physical charging stations.

 for identifying EV drivers and starting/stopping charges.

 to transfer charging event data to the backend system for user billing.

, to enable CPOs to monitor station statuses (e.g., in-use, faulted).

Unlike proprietary protocols that lock you into a specific ecosystem, OCPP is vendor-agnostic and future-proof. It empowers eMobility providers to build scalable, secure, and flexible networks, critical as EV adoption accelerates globally.

Promotes interoperability in EV infrastructure

Reduces vendor lock-in with open standards

Supports real-time communication and smart charging

Backed by a global ecosystem of stakeholders

: Adopting the latest OCPP version (currently 2.0.1) ensures better security, ISO 15118 compatibility (Plug & Charge), and long-term scalability

Versions and evolution of the Open Charge Point Protocol

 has evolved to support new technical capabilities, stronger security, and better compatibility with modern charging infrastructure. While multiple versions exist, the most widely implemented today is 

 being the most current and feature-rich version. The following sections outline the key differences and improvements introduced in each.

Released as a major step forward from version 1.5 (now largely obsolete), 

 added a wide range of enhancements that made it the de facto industry standard for several years. Below is a summary of the most notable features and improvements introduced in this version.

 was introduced as a transport protocol, reducing data usage and enabling communication through NAT routers.

 were added to the ChargePointStatus enumeration, offering more insight into station status.

Changes to the structure of MeterValues.req to remove XML attributes, which supports JSON compatibility.

 in the enumeration allowed for more detailed station data (e.g., EV State of Charge).

 function enabled the central system to request data from the charge point.

A new Pending status was added to the RegistrationStatus enumeration used in BootNotification.conf.

, giving CPOs clearer guidelines for setup.

, including connector numbering and request/response handling.

(Please note: this extract comes from the 

, available in full from the Open Charge Alliance.)

OCPP 2.0 was introduced in April 2018. However, certain issues were later discovered, some significant enough to require backward-incompatible changes. For example, adjustments like increasing the security certificate length couldn't be resolved by documentation tweaks alone. As a result, OCPP 2.0.1 was released and is now the version recommended by the Open Charge Alliance for use in production environments.

As the OCPP standard evolves, it's essential for charging station operators and manufacturers to stay updated with the latest versions. Doing so ensures compatibility with the latest CSMS software and access to new OCPP features.

Compared to version 1.6, these newer versions introduced several impactful changes:

Significant security enhancements, addressing previous vulnerabilities.

 replaced older Status Notifications for improved infrastructure control.

 to support more complex and larger-scale EV charging networks.

The official Open Charge Point protocol documentation consists of 7 parts:

JSON over WebSockets implementation guide

Building smarter, scalable EV charging networks with OCPP

As EV adoption surges, seamless communication between charging stations and backend systems becomes a foundation, not a feature. The Open Charge Point Protocol (OCPP) offers exactly that: a standardized, future-proof way to ensure your infrastructure can grow, adapt, and stay secure.

Whether you're deploying your first charging station or you're already a larger network operator, OCPP compliance ensures you're staying ahead.

FAQs about OCPP (Open Charge Point Protocol)

OCPP is an open-source communication protocol for EV charging stations that ensures different hardware and backend systems can work together seamlessly. It improves 

, scalability, and network management for charging station operators.

The OCPP (Open Charge Point Protocol) enables real-time, two-way communication between EV charging stations and Charging Station Management Systems (CSMS). Using WebSocket and JSON (in versions 1.6 and 2.0.1), the protocol manages key operations like session authorization, billing data transfer, remote control, diagnostics, and smart charging. OCPP standardizes how messages are structured and exchanged, ensuring interoperability across different hardware and software proprietary systems in the EV ecosystem.

What's the difference between OCPP 2.0 and 2.0.1?

OCPP 2.0.1 is an enhanced and stable version of OCPP 2.0, introduced to address technical gaps, security vulnerabilities, and interoperability issues found in the original 2.0 release. While both versions support advanced features like Plug and Charge (via ISO 15118) and smart charging, OCPP 2.0.1 includes critical fixes without backwards compatibility, making it the version officially recommended by the Open Charge Alliance for all new implementations. It ensures smoother deployments, better security compliance, and full compatibility with certified systems.

No. OCPP protocol is a recommended but not mandatory standard. Hardware manufacturers and CPOs are encouraged to adopt it and get OCPP certification for greater interoperability and flexibility.

 capabilities, allowing electric vehicles to automatically identify themselves and begin charging without manual authorization.

What is the Solidstudio OCPP Gateway, and why is it essential for EV charging infrastructure?

 is a hardware-agnostic bridge that connects EV charging stations with backend software using the OCPP 1.6 or 2.0.1 protocol. Designed for stability and scalability, it enables Charge Point Operators to manage remote diagnostics, smart charging, and transaction handling across diverse EV charger models, saving time, boosting reliability, and ensuring full OCPP compliance.

What is the Solidstudio OCPP Proxy, and how does it simplify EV charging network operations?

 is a lightweight, high-performance tool that enables dynamic routing of OCPP WebSocket traffic between charging stations and multiple central management systems. Ideal for network migrations, testing, and disaster recovery, it allows Charge Point Operators to duplicate traffic, inspect logs, debug communication, and switch backend connections with a single click, ensuring seamless interoperability across large-scale EV infrastructures.

Learn how OCPP enables interoperability in EV charging. Explore the key differences between OCPP 1.6, 2.0, and 2.0.1, and why they matter.

OCPP: The Open Standard for EV Charging You Need to Know

Understand EV charging protocols like OCPP, OCPI, OCHP, and eMIP.

Aldona is a Content Manager whose ultimate goal is to tell you a good story, not compromising on the knowledge-sharing part.

Aldona Krysiak-Adamczyk

As electric vehicles go mainstream, charging them isn't just about plugging into the nearest station. Behind every charge is a digital handshake, a complex conversation between the EV, the charger, the backend system, and sometimes even the power grid. That conversation? It's powered by EV charging protocols.

In this guide, we'll unpack the four most important ones: OCPP, OCPI, OCHP, and eMIP. They're the backbone of a connected, scalable, and future-proof EV charging ecosystem.

EV charging, or communication, protocols allow different components of the electric vehicle charging ecosystem to “talk” to each other. They define how data is exchanged between:

Charging networks and eMobility service providers


They manage physical connections with electric vehicles and in-vehicle communication (e.g., CCS, CHAdeMO, 


They manage digital communication and backend processes (e.g., OCPP, OCPI, OCHP, eMIP).

As the entire electric vehicle market accelerates, the need for seamless, reliable, and intelligent charging experiences is more critical than ever. Communication protocols form the foundation of this ecosystem, ensuring that all components of the charging infrastructure communicate seamlessly, regardless of the manufacturer, network, or location.

Without common communication protocols, electric vehicles would be locked into proprietary systems. Protocols like 

 allow hardware and software from different vendors to work together. This ensures that a charger from Brand A can be managed by a platform from Provider B and accessed by a user from Network C, all without friction.

 enable drivers to charge across multiple networks with a single account or RFID card. Just like mobile roaming, these international standards allow drivers to use various charge point operators, creating a better user experience and broader infrastructure access.

, charger availability, pricing updates, session tracking, and energy usage. Protocols ensure this information is shared instantly and accurately between stations, backend systems, and service providers, enabling features like dynamic pricing and remote diagnostics.

 enable advanced energy management features, including 

 (V2G) functionality. These tools are critical for grid stability as EV demand scales, allowing charge point operators to optimize based on time-of-use rates and grid load.

As the EV industry grows, operators need protocols that support hundreds or thousands of units. Open standards allow plug-and-play integration of new hardware, software upgrades, and service expansions, without getting locked into a single vendor ecosystem.

EV charging infrastructure is only as effective as the protocols that connect its various components. While physical standards like CCS or CHAdeMO govern how power flows, the communication protocols ensure everything behind the scenes works, from session management and remote monitoring to billing and roaming.

In this section, we'll break down four of the most important backend communication protocols: OCPP, OCPI, OCHP, and eMIP. Each plays a unique role in enabling interoperability, enhancing user experience, and helping operators build scalable, intelligent, and future-proof charging networks.

(OCPP) is the most widely adopted communication standard in the EV charging world. Developed by the Open Charge Alliance, OCPP defines how EV charging stations communicate with central management systems (

), essentially the backend software that monitors and controls the network.

OCPP allows EV charging stations and backend platforms to:

Start or stop charging sessions remotely as soon as the electric vehicle is connected

Monitor charging status and station health

Collect detailed data on usage and energy consumption

Enable smart charging and grid integration features

By separating the hardware (charging station) from the software (management system), OCPP gives operators the freedom to 

, helping avoid vendor lock-in and allowing greater flexibility in scaling a charging network.

Supports basic smart charging, remote control, and charge session data

JSON and SOAP support for flexible integrations

Smart charging profiles and reservation systems

Better diagnostics and event notifications

Open and vendor-neutral: Anyone can implement it - no licensing required

Widely supported: Compatible with thousands of electric vehicle supply equipment (EVSE) models worldwide

Future-ready: Enables advanced use cases like V2G, load balancing, and dynamic pricing

 is a protocol designed to enable roaming and data exchange between EV charging networks. Developed by the EVRoaming Foundation, OCPI allows EMSPs and CPOs to work together, so EV drivers can seamlessly use chargers across different networks, much like mobile phone roaming.

OCPI defines how two charging networks exchange key information, including:

Authentication and access control (via tokens or RFID cards)

Charging session details and billing records

In essence, OCPI enables a driver with one account or app to locate, access, and pay for charging services on multiple, unaffiliated networks, without setting up separate accounts.

Uses JSON for lightweight, flexible data exchange

Supports pull and push modes for real-time updates

Openly available and not controlled by a single company

Roaming: Crucial for public EV charging access across regions and networks

User-friendly: No need for multiple apps or subscriptions

Operator-friendly: Supports automated settlement, contract management, and service level agreements

Data-driven: Helps improve charger availability, reliability, and customer transparency

Simplified roaming: One connection to a clearing house = access to many networks

Standardized integration: Reduces custom development for each partner

Efficient scalability: Particularly beneficial in complex, multi-party environments

Regulatory compliance: Aligns with many EU transparency and access mandates

(OCHP) is a communication standard that enables interoperability between EMSPs and CPOs through a centralized clearing house. Developed and maintained by Smartlab Innovationsgesellschaft mbH, OCHP is widely used in Europe, especially in markets like Germany, to simplify roaming and backend integration.

, OCHP operates via a clearing house model. In this setup, all roaming communications (authentication, pricing, billing, and charger status) flow through a central intermediary platform, making it easier to manage relationships between many parties.

Charger availability and location sharing

Real-time session management and CDR (Charge Detail Record) exchange

Roaming authorization via a single interface

Pricing and contract updates between EMSPs and CPOs

Enables both push and pull communication models

Commonly paired with clearing house platforms like ladenetz.de

 is a communication standard that enables interoperability between EMSPs and CPOs through a centralized clearing house. Developed and maintained by Smartlab Innovationsgesellschaft mbH, OCHP is widely used in Europe, especially in markets like Germany, to simplify roaming and backend integration.

Understand EV charging protocols like OCPP, OCPI, OCHP, and eMIP. Learn how they power interoperability, smart charging, and network scalability.

Complete Guide to EV Charging Protocols (OCPP, OCPI, OCHP)

Calculate the benefits and scalability potential of licensed EV charging software. Our free ROI calculator compares your SaaS investment with what it looks like with our licensed model. You can enter whichever number of chargers you like (the more EV chargers, the more you save).



The ROI calculation is based on a three-year period.

Operational costs reduction

Instant increase in company valuation

Price transparency

Modern technology stack

High flexibility levels of the solution

Possibility to hire a dedicated dev team that will work on your Key Selling Points implementation

Improved time to market

Opportunity to add features to improve competitiveness and uniqueness

Unlike with SaaS, with license costs don't rise linearly with an increased amount of chargers, meaning that even if the price is higher upfront, it becomes a lot less expensive with time and growth.

The benefits go beyond just the financial aspects, as the license also comes with an opportunity to gain total ownership of the solution. It includes the right to manipulate the source code, giving our clients full control over the intellectual property of developed functionalities. This approach liberates our partners from reliance on third-party providers and allows them to tailor the software precisely to their needs


Finally, technical support and overview can be provided by Solidstudio, which leaves out the necessity of any operational changes. All this, while keeping the benefits of full ownership that come with a license.

Our license in a nutshell

Use our free ROI calculator to compare your current EV charging platform costs with our licensed model. The more sockets you manage, the more you save. See your 3-year savings in seconds.

With the growing number of available solutions, we believe that the correct software decisions require evaluation beyond just features and technicalities. Most digital products are available strictly via SaaS, which becomes financially and operationally problematic once businesses start to scale.

The licensing model is the most profitable for larger operators planning further growth.

EV Charging Station ROI Calculator: Save Big as You Scale

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