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.

The increasing electrification of transportation demands the development of more energy-efficient solutions, where additive manufacturing (AM) of electrically conductive components presents new opportunities. The design flexibility of AM enables unique innovations; however, it also introduces challenges due to additional process parameters affecting part production. A key concern in the use of laser powder bed fusion of metal (PBF-LB/M) manufactured parts is their material properties, which are further influenced by part plane orientation during fabrication. Previous research has focused on copper-aluminum dissimilar welding, but the specific challenges posed by AM techniques have not been fully explored. This study investigates the welding behavior concerning resistance and intermetallic layer formation. Nickel-plated copper sheet metal samples were welded to AM aluminium samples using a continuous wave single-mode fiber laser with scanner optics in a lap joint configuration. Before welding, the interface surface of the AM samples was machined to exclude the surface roughness variance effect on the result. During the experiments, the welding´s optical laser power was constant at 2kW and variations were made in welding speed ranging from 1200 mm/s to 400 mm/s in 200 mm/s increments. Electrical resistance measurements were taken using a high-precision micro resistance meter with a 4-wire Kelvin testing method, also hardness testing, tensile testing, and energy dispersive spectroscopy (EDS) analysis were conducted. The results revealed that intermetallic compounds formed during welding, influencing joint properties. At a lower welding speed, more aluminium was mixed with copper which led to the weld solidification cracking. The optimum welding speed was between 800 and 1000 mm/s for this study test setup.

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.

The integration of additive manufacturing's design versatility with a push for electrification can lead to unique innovations. In this context, when discussing welded joints, their quality and reliability play a significant role. The restricting factor for the use of laser powder bed fusion of metal (PBF-LB/M) additive manufactured (AM) parts is often their surface quality in the as-built state. In addition, the surface quality changes when part plane orientation changes. In this study, AlSi10Mg aluminum test samples were additive manufactured in seven different build angles. The AM samples were glass bead blasted after manufacturing, and the surface roughness of the joint surface area was optically measured. After the measurement, the AM samples were welded to nickel-plated copper and aluminum sheet metals. A continuous wave single-mode fiber laser with scanner optics was used to carry out the welding experiments in lap joint configuration. The structural and mechanical properties of the welds were evaluated by the macroscopic images of weld cross sections and tensile testing of the samples. The electric resistivity of the samples was also tested. Based on the measurement results of the samples, the impact of surface quality was discussed. The results indicated that there was no clear effect of building angle on the final weld quality. The worst surface quality in the joint area was on the test pieces in which the joint surface was facing down toward the build plate.