ISO 15118 Protocol Software Development Guidelines (IV) – Specific Issues for On site Charging

The previous article introduced the software implementation of the European standard CCS 15118 protocol. As is well known, in order to achieve the practical application of charging pile products, it is also an extremely important step to test the integration with real vehicle charging. This article will analyze and discuss some specific issues related to the protocol encountered during the on-site operation of European standard charging stations overseas.

At present, there are many brands of new energy vehicles overseas, some of which are self-developed EVCCs, while others purchase mature EVCC modules from third parties. Although different companies also follow the CCS standard in the implementation of EVCC, the 70121 and 15118 protocols themselves do not specify every detail and exception, and each company has its own understanding of the protocol, so there will be different approaches in handling details. In actual operation, charging stations have to face numerous different brands of cars. Once charging fails, customers generally believe that it is a problem with the station rather than their own car. Therefore, how to improve the compatibility, stability, and charging success rate of charging stations is an important but thorny issue that station companies commonly face.

Below is an analysis and discussion of the problems we encountered in testing different brands of car models in multiple overseas locations. This will not only help everyone avoid detours, but also deepen their understanding of the agreement through discussion. (Considering sensitivity, we will not provide specific explanations of the brand of the car model later, and will use a certain model instead.)

The above is an analysis of some typical problems encountered during the actual vehicle charging docking test in overseas markets. Overall, due to the charging characteristics of new energy electric vehicles, even a high-power charging station requires a certain amount of time to fully charge the vehicle. After inserting the charging gun and starting the charging process, users often leave the charging station to do other things, and only return after it is expected to be fully charged. If the charging is interrupted due to certain issues, the user experience will be very poor. So the stability and compatibility of charging stations are important indicators for improving user experience. For SECC products, in addition to ensuring the reliability and stability of hardware design, the principle of software design is that SECC generally does not actively interrupt the process unless it may cause safety issues. It is up to the vehicle or pile end to determine whether termination is necessary to improve compatibility and fault tolerance.

The testing questions raised above are just a starting point for discussion, and we also hope that colleagues with practical experience in vehicle integration can participate in the discussion together, exchange ideas, avoid pitfalls and detours, and accelerate the pace of domestic charging piles and new energy vehicles entering overseas markets.