Development of Battery Systems | NewsLIGHT #15 | IKA

The high-voltage battery is currently one of the focus points in the development processes of battery electric vehicles. In addition to cell development, the main topics here are the E/E architecture, the thermal management and the improvement of the mechanical properties and safety of the system.

While many battery electric vehicles are still characterized by so-called conversion design due to the use of derivatives of combustion engine vehicles, current developments are resulting in dedicated vehicles with a purpose design. This paradigm shift leads to fundamentally changed boundary conditions.

The development of efficient and cost-effective solutions therefore requires a comprehensive understanding of the entire vehicle, the possible operating conditions and the resulting energetic and mechanical requirements as well as the legal framework for the certification of battery systems. The Institute of Automotive Engineering (ika) of RWTH Aachen University has acquired broad expertise in the definition, design, prototyping and commissioning of battery modules and systems and can contribute to efficient development with established processes.

This process starts with a prioritization of the relevant requirements, e.g. from norms and standards and from OEM requirements. On this basis, a specific concept is defined. The system development is carried out in an interdisciplinary, agile process, covering modularization and structural design, E/E architecture and thermal management. ika has comprehensive and in-depth technological expertise in the relevant areas of battery system development. Specialists from the Body, Powertrain, Electrics/Electronics, Acoustics and Thermal Management divisions work hand in hand. The latest software tools are used for efficient system design. The corresponding standardized as well as specialized test benches for validation are also available at ika. These include an E/E battery test bench, a thermal management test chamber, a servo-hydraulic mechanical testing center and a crash test facility.

In terms of crashworthiness not only the passengers, but also the traction battery needs to be protected in order to prevent hazardous situations. Therefore, the passenger compartment as well as the battery housing both have to meet high mechanical performance requirements. This usually leads to the design of heavy structures, which contradicts the idea of an efficient, low cost lightweight construction. In order to achieve an efficient design on full vehicle level, the structural integration of different components of the battery housing into the body in white (BiW) or vice versa is the main focus of an ongoing collaborative project, funded by the German federal ministry for economic affairs and energy (BMWi).