What gets in the way of smooth and reliable charging of e-vehicles? In a project funded by the Federal Ministry for Digital and Transport (BMDV), stakeholders from industry and science diagnosed sources of errors and on that basis, drafted a catalogue of measures for a more user-friendly public charging infrastructure.

Berlin, 20.01.2023 – The participants in the ‘Wirkkette Laden’ project have presented the final results of their two-year collaboration. Coordinated by NOW GmbH and Project Management Jülich, the consortium had systematically analysed which errors occur when charging electric cars and how sources of error can be overcome. One of the objectives was to define a binding catalogue of measures for market participants involved.

In addition to consortium leader Charging Interface Initiative (CharIN) e.V., the University of Stuttgart, the Fraunhofer Institute for Industrial Engineering IAO, ABB, Stromnetz Hamburg, BMW, EWE, EcoG, Digital Charging Solutions and IONITY were involved in the project. The federal government funded the project under the Electric Mobility funding guideline in the amount of 1.1. million euros. The National Centre for Charging Infrastructure, under the umbrella of NOW GmbH, supported the project in terms of content.


Based on data from real charging processes, errors and the causes of error were identified that most commonly occur along the ‘charging effect chain’. This was supplemented with findings from real-lab trials with test subjects from Munich and Hamburg. 61 people who use an electric vehicle documented their charging processes for six months.

Various vehicle models from different manufacturers and charging stations ranging from 11 kW to 350 kW were used. For the faulty charging processes that took place at the charging infrastructure of the project partners, the feedback of the study participants was evaluated and the associated data records of the participating partners examined. In 44 per cent of cases, the error was due to a technical problem at the charging station.

As a further step, the consortium analysed the quality of standards and norms that specify the entire charging process in each case.


The „Big Picture“ (PDF) graphic provides an overview of the charging ecosystem. It shows the many interfaces that occur between searching for a charging station via app to charging, to the payment process between customers, equipment manufacturers, charging station operators, network management and electricity suppliers. Errors that occur when charging are categorised according to priority and urgency, in terms of finding a solution.

With the „12 design premises for public charging stations“ (PDF), the consortium has defined a binding catalogue of measures for the market participants concerned.

The measures are derived from two use-oriented studies and contain recommendations which include the uniform use of the individual EVSE identification code, with which each station is provided or part thereof (EVSE stands for Electric Vehicle Supply Equipment).

Oliver HochHead of Battery-Electric Mobility and Charging Infrastructure at NOW GmbH said: ‘Only through the broad acceptance of electric mobility within the population can the federal government’s 15 million car objective be reached. The ‘Charging effect chain’ project focusses on a key aspect of electric mobility: charging. Because it is only when we have reliably functioning and smooth charging processes can we succeed in breaking down barriers to electric mobility. R&D projects like these are fundamentally important to systematically analyse processes and develop solutions that become marketable products.”

Johannes Pallasch, Spokesperson of the Management team at the National Centre for Charging Infrastructure stated: “Charging must be user-friendly and simple. Digitalisation is a decisive factor for increasing user-friendliness – it makes finding free charging stations, the charging process itself and the payment process more transparent. That’s why I’m delighted about the successful conclusion of our joint ‘Charging effect chain’ project and the ’12 design premises’ for publicly accessible charging stations. The results of the ‘Charging effect chain’ provides companies that operate charging infrastructure with concrete approaches to solutions so they can continue to improve the charging experience. We will also take these into account in implementing the Charging Infrastructure Master Plan II.”

Claas Bracklo, Chairman of CharIN e.V.: “The productive cross-sector collaboration of the project partners enabled the interfaces of the charging ecosystem to be defined. With the further development of the charging use cases and the requirements for an ideal charging station, the foundations have been laid for continuous improvement of the charging experience. Now we must agree the specified scope in the relevant forums and adequately address the fields of action that have been identified in the framework of follow-up projects.”

More information on the ‘Charging effect chain’ project: www.charin.global/technology/customer-jounrey

An insight into the real-lab trial: User Experience an Ladesäulen: Erkenntnisse aus dem Reallaborversuch des Projekts »Wirkkette Laden« (YouTube)

Improving charging quality of electric vehicles through the systematic analysis of sources of error in the effect chain: www.now-gmbh.de/projektfinder/wirkkette-laden

Project process fact sheet: www.now-gmbh.de/wp-content/uploads/2021/02/Steckbrief-zum-Projektfortschritt-Wirkkette-Laden.pdf