Ensuring the precision and repeatability of component assembly in the production of electric vehicle (EV) battery modules requires fast and accurate measuring methods. The durability of EV battery packs depends on the quality of welded connections, therefore exact positioning of the module components is critical for ensuring safety in exploitation. Laser welding is a non-contact process capable of welding dissimilar materials with high precision, for that reason it has become the preferred joining method in battery production. In high volume manufacturing, one of the main production challenges is reducing the time required for assessment of dimensional and geometrical accuracy prior to joining. This paper reviews the challenges of EV battery design and manufacturing and discusses commercially available scanner-based measurement systems suitable for fabrication of battery pack components. Versatility of novel metrological systems creates new opportunities for increasing the production speed, quality and safety of EV battery modules.

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The present work provides an overview on an additive manufacturing (AM) design case of a novel battery cell lid structure (patent pending) for electrical vehicle applications. The benefits of AM have not yet been explored on metal case structures of prismatic battery cells. The method allows the manufacturing of complex hollow structures and integration of multiple functions in one part. The main challenge is to address thermal management in an optimal location in the battery cell. More efficient charging and discharging by maintaining the batteries at optimum operating conditions allows a longer battery lifetime. Recent research shows that elevating the charging temperature enables significantly shorter charging times. The aim of this study is to develop a lid structure to support higher peak current, faster charging, and reduced production steps and enable mass customization. The optimum performance simulated with computational fluid dynamics calculations is realized to determine the optimum design. The design case study is verified via laser powder bed fusion prototypes. This study shows that it is possible to produce integrated thermal management liquid channels to the battery lid. Significant improvement is achieved with localized battery cell temperature management. The novel design integrates six critical functionalities of the lid in one part. The design of the features is optimized to avoid support structures in AM and to maximize the number of parts in the printing chamber volume. The better thermal management extends the driving range of the vehicle and improves vehicle safety. Reducing the parts significantly simplifies cell production.

Evolution of additive manufacturing has allowed increased flexibility and complexity of designs over conventional manufacturing e.g. formative and subtractive manufacturing. Restricting factor of laser powder bed fusion of metals (PBF-LB/M) additive manufacturing is the as-built surface quality. To promote an understanding of the surface roughness and suitable surface measuring technologies octagon shaped tool steel 1.2709 samples was developed and manufactured. Different surface measuring technologies was also literary reviewed. Studied samples were manufactured with commercially available laser-based powder bed fusion system using standard parameter set provided by the system manufacturer. Surface roughness was measured from top and down skins from multiple different building angles in a way that process specific effects, such as direction of movement of the powder re-coater, was considered. Based on these measuring results of the samples the effect surface inclination are discussed. The results show that building angle strongly affects to surface roughness of laser-based powder bed fused parts. Surface roughness was measured to be more than five times worse in unsupported angle manufactured down facing surfaces when compared with vertical walls.