1. What is OCPP: The Universal Language of EV Charging

OCPP (Open Charge Point Protocol) is the most widely adopted open communication protocol in the global EV charging industry. Maintained by the Open Charge Alliance, it defines standardized communication between charging stations and backend Charging Station Management Systems (CSMS), enabling chargers from different manufacturers to connect to any operator's management platform and breaking vendor lock-in.

The core value of OCPP is interoperability. Before OCPP, each charger manufacturer used proprietary protocols, locking operators into a single vendor's ecosystem. OCPP changed this: smart EV charger products supporting the protocol can connect to any OCPP-compliant CSMS, giving operators freedom to choose hardware and software suppliers independently and reducing total cost of ownership.

Figure 1: OCPP Architecture: Charger-to-CSMS Interoperability

Three main OCPP versions exist today: OCPP 1.6 (released 2015), OCPP 2.0.1 (released 2020), and OCPP 2.1 (released 2024). OCPP 1.6 is the most widely deployed version globally, with a mature ecosystem and long-proven compatibility. OCPP 2.0.1 offers significant improvements in feature completeness and security and is gaining adoption. OCPP 2.1 is the future-facing latest standard. ev charger manufacturers china offer products across both 1.6 and 2.0.1, from wallbox EV chargers and portable EV chargers to high-power liquid cooled DC charger systems.

2. OCPP 1.6 vs 2.0.1: Key Differences and Selection Advice

OCPP 2.0.1 is not a simple incremental upgrade from 1.6 — it is an architectural rewrite, and the two are not backward compatible. According to Open Charge Alliance documentation, OCPP 2.0.1 introduces over 100 message types (compared to approximately 25 in OCPP 1.6) and adds several critical feature modules.

Figure 2: OCPP 1.6 vs 2.0.1 Feature Comparison

First, the Device Model. OCPP 2.0.1 introduces a unified device model where every component and variable on the charger reports standardized data, allowing backends to query voltage, temperature, connector status, and more. OCPP 1.6 only provides limited information through configuration keys.

Second, enhanced security. OCPP 2.0.1 mandates TLS 1.3 encrypted transport and adds security profiles, certificate management, and security event reporting. As cybersecurity becomes increasingly important — particularly with the EU CRA regulation approaching full enforcement — this upgrade is critical for commercial operations.

Third, native ISO 15118 Plug & Charge support. OCPP 2.0.1 natively supports ISO 15118 Plug & Charge, enabling automatic authentication and billing when the user plugs in — no RFID card or app required. This cannot be achieved natively with OCPP 1.6.

Fourth, enhanced smart charging. OCPP 2.0.1 supports finer-grained power scheduling, charging priority settings, randomized off-peak delay, and intelligent current limiting during grid peak hours. These capabilities are essential in multi-charger deployment scenarios such as apartment buildings and commercial parking lots. OCPP charger products from ev charger manufacturers china that implement these features offer significant advantages in dense deployment scenarios.

Fifth, display and messaging control. OCPP 2.0.1 allows remote control of charger screen content, enabling operators to push customized messages, advertisements, or operational notifications to users.

In 2023, OCPP 2.0.1 was adopted as IEC international standard IEC 63584, marking its upgrade from a de facto industry standard to a formal international standard. On version selection, each has its applicable scenarios: OCPP 1.6 offers a mature ecosystem, broad platform compatibility, long-proven stability, and lower deployment costs — suitable for budget-sensitive projects with basic remote monitoring and billing needs, or projects requiring compatibility with existing 1.6 platforms. OCPP 2.0.1 offers granular device management, stronger cybersecurity mechanisms, native ISO 15118 Plug & Charge support, and more comprehensive smart charging features — suitable for new projects with higher security and intelligence requirements and long-term operational plans. Procurement teams should choose based on project functional requirements, budget, and existing platform ecosystem, rather than simply pursuing the highest version number or the lowest cost.

3. Core OCPP Features: From Remote Monitoring to Smart Load Management

OCPP-compliant smart EV charger products enable a range of advanced management functions that directly impact operational efficiency and user experience.

Figure 3: OCPP 2.0.1 Core Features Value Assessment

Remote monitoring and fault alerting is the most fundamental and valuable OCPP feature. Operators can view real-time status, charging power, connector temperature, and other parameters for every charger on the management platform. When a fault occurs, the system automatically reports error codes, enabling remote diagnosis by maintenance personnel and significantly reducing response time. Industry experience shows that comprehensive remote monitoring can reduce mean time to repair by over 40%.

Smart charging and load balancing is the core function for multi-charger scenarios. In locations with limited grid capacity — such as apartment buildings and commercial parking lots — if all chargers run at full power simultaneously, transformer overload may occur. OCPP smart charging dynamically allocates power per charger based on grid capacity, enabling deployment of more chargers without additional grid infrastructure investment. This capability is critical for reducing installation costs and accelerating deployment.

OTA firmware updates allow operators to remotely update charger firmware through the management platform without on-site visits. This means bug fixes, feature rollouts, and security patches can be deployed quickly, dramatically reducing maintenance costs. OCPP 2.0.1 also supports firmware rollback, ensuring automatic recovery if an update fails.

Billing and payment management through OCPP enables real-time upload of charging duration, energy, and cost data to the management platform, supporting multiple billing models (by time, by energy, by power tier). Combined with ISO 15118 Plug & Charge, the user experience reaches "plug to charge, unplug to go" frictionless payment. EV charging solutions from ev charger manufacturers china that integrate these capabilities are increasingly preferred by commercial operators.

4. OCPP and ISO 15118: The Technology Stack for Plug & Charge

OCPP and ISO 15118 are complementary protocols. OCPP handles communication between the charger and the backend management system, while ISO 15118 handles communication between the electric vehicle and the charger. Together they enable a complete Plug & Charge experience: when the user plugs in, the vehicle sends identity via ISO 15118, the charger forwards it to the CSMS via OCPP for authentication and billing authorization — all without any user action.

ISO 15118 Plug & Charge is advancing rapidly in Europe, where Volkswagen, BMW, Mercedes-Benz, and other brands support it in multiple models. In North America, Plug & Charge is also spreading quickly with the adoption of the NACS connector. For procurement teams targeting global markets, whether to choose products supporting both OCPP 2.0.1 and ISO 15118 should be based on the vehicle support situation and project requirements in the target market.

5. Procurement Advice: How to Select OCPP-Compliant EV Chargers

First, verify OCPP version and certification. Require suppliers to provide OCPP compliance declarations and verify product certification on the Open Charge Alliance website. Distinguish between "supports OCPP" (partial implementation possible) and "OCPP certified" (officially tested and verified).

Second, evaluate whether smart charging capabilities meet project needs. Smart charging requirements vary significantly across projects — assess whether the supplier's product capabilities are sufficient for the actual deployment scenario (such as multi-charger dense deployment, grid capacity constraints, etc.) rather than simply pursuing the maximum number of features.

Third, validate interoperability. Request interoperability test reports with major CSMS platforms. OCPP charger products with comprehensive interoperability testing records significantly reduce deployment risk.

Fourth, assess cybersecurity capabilities. With the EU CRA regulation approaching full enforcement, cybersecurity will become a hard requirement for charger exports. Understand the supplier's overall approach to product security design and firmware update mechanisms.

Fifth, evaluate scalability and long-term support. Choose products with modular design that can extend functionality through firmware updates, and understand the supplier's protocol version upgrade roadmap. The ability to upgrade to newer protocol versions will impact equipment lifecycle value.

6. Outlook: OCPP 2.1 and the Future of Charging Ecosystem

OCPP 2.1 builds on 2.0.1 with enhanced display control, advanced security, and smart charging, and introduces support for Vehicle-to-Grid (V2G) bidirectional charging. As V2G technology develops, chargers will evolve from one-way charging devices into flexible grid regulation resources, and OCPP will play an increasingly important communication hub role.

For charger procurement teams and operators, OCPP has transitioned from a "bonus feature" to a "must-have." Chargers without OCPP support will become increasingly difficult to accept in commercial operations. On version selection, OCPP 1.6 and 2.0.1 each have their applicable scenarios: 1.6 is mature, stable, broadly compatible, and lower cost; 2.0.1 offers more comprehensive features, stronger security, and is more future-facing. Procurement teams should select the appropriate version based on project functional requirements, budget, existing platform ecosystem, and long-term planning.

Data Sources

1. Open Charge Alliance, "Open Charge Point Protocol (OCPP) Official Documentation", 2026

2. Open Charge Alliance, "What is new in OCPP 2.0.1" White Paper, 2024

3. Open Charge Alliance, "What's New OCPP 2.1" White Paper, 2024

4. IEC, "IEC 63584: Electric vehicle charging system communication protocol", 2023

5. Joint Charging, "OCPP 2.0.1 & CSMS Integration Guide for EV Charging CPOs", July 2026

6. Open Charge Alliance, "Improving Uptime with OCPP" White Paper, 2024

7. ISO, "ISO 15118: Road vehicles - Vehicle to grid communication interface", 2024