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In this paper a new cutting technology similar to hard turning is presented to cut rotationally symmetric parts made of hardened materials. This novel technology, which is named rotational turning, is based on a combination of hard turning and circular milling. An analytical model is developed to describe the engagement parameters between tool and workpiece. It is shown by the model, that the virtual tool corner radius in rotational turning, which takes effect during the cutting process, is more than 50 times larger than in state of the art hard turning. Due to this, feed marks, which are common in turning, can be reduced to a level, where they are not measurable anymore. It can be shown in experiments, that the minimum achievable surface roughness is therefore not limited by the feed rate anymore, like in turning processes usual, but by other effects like the waviness of the cutting edge

Due to the rising interest in electric vehicles, the demand for more efficient battery cells is increasing rapidly. To support this trend, battery cells must become much cheaper and "greener." Energy consumption during production is a major driver of cost and CO 2 emissions. The drying production step is one of the major energy consumers and cost drivers. The technological approach of "dry coating" allows the energy-intensive drying step to be eliminated for significant energy and cost savings. However, there are numerous emerging dry coating technologies that differ significantly in physics, chemistry, and readiness levels. Moreover, typical methodological procedures for technology selection remain less applicable to the early stages of technological development. Both issues raise the questions, "What is the most promising dry coating technology?" and "How do we identify it?" To answer these questions, a comprehensive, systematic technology benchmark was conducted. Following a four-step analytical approach, based on the nominal group technique, qualitative content analysis, and multicriteria decision analysis, different dry coating technologies were identified, analyzed, and cross-compared. This was performed qualitatively and quantitatively. We also forecast which factor will impact the application of the most promising technologies for CO 2 emission rate reductions and cost savings in 2030. In summary, four different technologies were identified with a high chance of technological breakthrough within the next 3-5 years. By applying these technologies, 4.76 million tons of CO 2 could be saved per year by 2030.

The global demand for electric vehicles is increasing exponentially, as is the demand for lithium-ion battery cells. This has led to a strong ongoing competition among companies to achieve the lowest battery cell production cost. Herein, to provide guidance on the identification of the best starting points to reduce production costs, a bottom-up cost calculation technique, process-based cost modeling (PBCM), for battery cell production is reproduced and validated by drawing on a consistent dataset of a real battery cell production plant. The model is based on teardowns of a real battery cell factory and will prove useful for planning activities of today's, so-called, "giga factories." The PBCM performed in the present study involves discussions on, e.g., production balancing, relocation of factories to low-wage countries, usage of new production and cell technologies, etc. The use of novel approaches, such as tabless cell design, dry coating, and NMC811 chemistry, is discussed. Finally, the ways in which battery cell production costs can be reduced further in the forthcoming years are shown, and implications for researchers, practitioners, and policy makers are provided.