HoliCPV

Currently, Fiber-Reinforced Plastics (FRP) with thermic stability, used for hydrogen pressure tanks are only to a limited extent suitable for recycling. The project HoliCPV aims to develop pressure tanks made of thermoplastic Carbon Fiber-Reinforced Plastics (CFRP) to enable resource-saving, lightweight construction, and better recyclability. To achieve this, HoliCPV will develop and connect digital tools within a holistic winding toolchain and tailored CAD/CAM software solutions to bring the newly developed production technologies into industrial applications.

For mobile applications such as cars, the demands on hydrogen pressure tanks are twofold: they must endure substantial mechanical stress while maintaining a lightweight profile, all while withstanding the diverse array of thermal and chemical pressures encountered throughout their lifecycle. Addressing these challenges, Carbon Fiber-Reinforced Plastics (CFRP) have emerged as a preferred material for commercial pressure tanks due to their robust yet lightweight composition and exceptional resistance to heat. However, despite the significant weight reduction potential offered by CFRP, their resistance to heat makes them difficult to recycle.

The solution consists of a new type of recycling process, based on thermoplastic Fiber-Reinforced Plastics, which allows the continuous fibers to be fully recovered in high quality by melting the tape material on local level. In addition to better recyclability, this offers the possibility of further reducing the weight of the pressure tanks and thus increases the potential to save costs and CO2. Therefore, the project HoliCPV aims to create a holistic digital toolchain for winding hydrogen pressure tanks made of thermoplastic Carbon Fiber-Reinforced Plastics. The project’s success will provide businesses in the automotive industries with an economic advantage by enabling lightweight construction and resource saving. This will be achieved by linking and further developing digital tools for filament winding within an interdisciplinary collaboration. The overarching goal of the utilization of HoliCPV is to bring the newly developed production technologies, as well as the digital toolchain, into industrial applications.

The HoliCPV toolchain consists of four core pieces: path planning and CAD/CAM software, process planning and data acquisition, structural mechanics and design, liner design and production. Additionally, the project has two main sub-goals. Firstly, relevant technologies will be developed and connected for the holistic optimization of a thermoplastic FRP pressure tank for hydrogen storage. Secondly, a digital twin will be developed for a thermoplastic FRP pressure tank for the purposes of quality assurance and recycling.

In the project, ModuleWorks will develop a CAD/CAM software tool as a functional component of the HoliCPV toolchain. This should make it possible to implement the design freedom that comes with the use of thermoplastic, unidirectional reinforced tapes (UD) in web planning and convert it into machine code. In addition, ModuleWorks will also develop interfaces to the other functional modules, the data-driven process model, and the FE design methodology, to enable automated data exchange across the entire digital process chain. Optimizing the path planning and the modelling of the FEM model will enable the merging of CAD data and prediction data from the process model, which should serve to simulate pressure tanks as realistically as possible. Also, a CAM software solution will be developed to enable unconventional winding strategies for thermoplastic FRP, considering the process model and the realistic mapping of tape material accumulation. In addition, the existing process model is extended by modern ML algorithms and integrated into the toolchain. By achieving the sub-goals, a consistent reduction in the use of resources along the entire value chain in the sense of the circular economy will be achieved, from resource-conserving production to the reduction of component weight in mobile use, to recycling strategies for reuse in secondary components.

As a result, the research work in the project HoliCPV will help to speed up the development cycles for advanced, future thermoplastic FRP pressure tanks optimized for weight and productivity, for various applications, such as mobility (passenger cars, passenger and freight transport, commercial and work vehicles) or semi-stationary storage. Thanks to HoliCPV, the newly developed production technologies will enable the full exploitation of the technological potential to meet present industry needs. Finally, the project will provide the basis for further developments of CAD/CAM solutions for winding FRP components with the integrated software solutions.