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Battery Packs: Design, architecture and evolving trends in electric vehicle energy storage systems
No full textBattery technology is an integral component of today's electrified system and renewable energy integration, playing a pivotal role in applications such as electric and hybrid vehicles, portable electronic devices, and stationary power storage. The battery pack is an integrated assembly of electrochemical cells arranged in a specific configuration to provide the desired voltage, current, and energy. This presentation will explore the fundamentals, architecture, and design considerations of battery packs, as well as the most recent innovations that are shaping the future of electric vehicle energy storage system. This presentation will address two critical questions: How do battery pack architecture and design choice affect performance, safety and longevity? What are the current and emerging trends shaping battery pack technology?At its core, battery packs contain cells grouped into modules that are then assembled into packs. These components can be configured in various series and parallel arrangements. This presentation will discuss how this arrangement determines the total pack voltage, rate capability and capacity. The design of a battery pack involves selecting the right type of cells (size and format), arranging them in a suitable configuration and incorporating safety features to prevent potential hazards, such as explosions and fires. Therefore, this presentation clearly and concisely covers key considerations in battery pack design including the various cell forms and their unique trade-offs in terms of energy density, cooling efficiency and mechanical stability. In ensuring battery control, safety and extending battery life, the role of the battery management system (BMS) in monitoring, protecting and balancing is discussed. Emphasis is laid on active and passive balancing with respect to efficiency, cost and complexity.Finally, this presentation will address current and future trends, such as battery swapping, combination of different battery chemistries and innovative cell-to-pack and cell-to-vehicle designs. These designs are aimed at simplifying design process by reducing unnecessary mass and increasing energy density
Training LLMs on HPC Systems: Best Practices from the OpenGPT-X Project
No full textThe training of large language models (LLMs) requires substantial computational resources, complex software stacks, and carefully designed workflows to achieve scalability and efficiency. This report presents best practices and insights gained from the OpenGPT-X project, a German initiative focused on developing open, multilingual LLMs optimized for European languages. We detail the use of high-performance computing (HPC) systems, primarily JUWELS Booster at JSC, for training Teuken-7B, a 7-billion-parameter transformer model. The report covers system architecture, training infrastructure, software choices, profiling and benchmarking tools, as well as engineering and operational challenges
Comparison of Different Methods to Determine Pedestrian Shoulder Orientation from Stereo Recordings
No full textBiocatalytic Tools for Late-Stage Functionalization: Advanced Alkylation Techniques with Prenyltransferases
No full textBeyond Carbon Capture and Storage - Direct Air Capture for Sustainable Hydrocarbon Production
No full textIR-Based Analysis of Flame Spread in Open and Ceilinged Room Corner Fire Experiments
No full textThree different room corner experiments (RCE) with 6mm thick poly(methyl methacrylate) (PMMA) panels were carried out in this study. The set-up is located under an exhaust hood and is closed to three sides with brick walls so that air is only entrained via one side. To ensure symmetrical flow conditions, the walls of the RCE were rotated by 45◦ relative to the room walls and the RCE setup was placed in the middle of the room. As an ignition source, a 10kW sandbed burner was used. Two open 1m high RCE configurations and one closed, where an inert calcium silicate ceiling was used, are investigated. In one of the open RCE configurations, the burner was turned off after 2 minutes, to investigate flame spread close to the corner not being dominated by the burner. By including a ceiling, the effect of the radiation feedback is investigated. All experiments were repeated at least three times. Among other measurements, two infrared cameras were used to track the flame front. An in-house software was developed for the IR-based flame front analysis, which will be publicly available. The heat release rate and the temperature measurements between the sample material and the insulation, show a very good repeatability. Furthermore, the analysis of both the IR data and the temperatures shows symmetrical behavior between both PMMA plates. It is shown that the ceiling has a strong impact on the flame spread pattern and velocity, the velocity is more than doubled compared to the open RCE configuration. Whereas the effect of turning off the burner for the open room corner is minor, only a small delay in heat release rate is observed
