The reduction of process time and costs of lithium‐ion‐battery (LIB) cells to make electromobility an ecological technology and economically accessible for everyone is a very crucial research topic. Within the production process of actual LIB cells, the electrolyte filling and wetting are very time‐consuming, and by association, cost‐intensive steps. Therefore, it is essential to investigate and understand the impact of several process parameters on the wetting time and product quality. This can be achieved by the visualization of the wetting progress and subsequent electrochemical characterization of the LIB cells. The monitoring is realized by wetting balance tests for electrodes and separators as well as a new and powerful thermographic method. In addition, different separators with different surface chemistries are tested to improve the production process, the actual cell design, and therefore the costs of the final battery cell.

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The motivation of this paper is to identify possible directions for future developments in the battery system structure for BEVs to help choosing the right cell for a system. A standard battery system that powers electrified vehicles is composed of many individual battery cells, modules and forms a system. Each of these levels have a natural tendency to have a decreased energy density and specific energy compared to their predecessor. This however, is an important factor for the size of the battery system and ultimately, cost and range of the electric vehicle. This study investigated the trends of 25 commercially available BEVs of the years 2010 to 2019 regarding their change in energy density and specific energy of from cell to module to system. Systems are improving. However, specific energy is improving more than energy density. More room for improvements is thus to be gained in packaging optimization and could be a next step for further battery system development. Other aspects looked at are cell types and sizes. There, a trend to larger and prismatic cells could be identified.

The most cost‐intensive components of the battery system for electric vehicles are the lithium‐ion battery cells. Thus, to reduce the overall cost of a battery system, a clear objective is to reduce the production cost of lithium‐ion battery cells. Cost drivers are to be identified, which are essential to enable potentials for cost reduction. In particular, the formation and aging process represents a high potential for process cost reduction because of its enormous process time expenditure. The automotive industry requires up to 3 weeks for the formation and aging process of a single lithium‐ion battery cell. Due to the high relevance of these processes, the research project OptiZellForm as part of the ProZell Cluster examines those production steps in detail. Environmental conditions such as mechanical load and elevated temperature as well as the electrical and chemical properties influencing the formation and aging process are investigated. The focus of this study is the investigation of the mechanical exertion and elevated temperature with regard to the reduction of the formation process duration and thus the reduction of the production cost. For this reason, a specially designed device is used to investigate these parameters for lithium‐ion battery cells.

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