E-Mobility Engineering 016 l Aurora Powertrains eSled dossier l In Conversation: Thomas de Lange l Automated manufacturing focus l Torque sensing insight l Battery Show Europe 2022 report l Sodium batteries insight l User interfaces focus

This can be achieved by means of simple geometric adjustments using adapters. The modularity means it is therefore possible to simply adjust one component – the adapter – and leave the rest of the plant peripherals unaffected. Heat is always produced in a battery during driving and charging, which must be dissipated to the outside to prevent overheating. This is done using a gap filler, a heat-conducting paste that is introduced into gaps between the modules and the cooling plate. Since the gap fillers are an important part of an electric car battery’s thermal management system, they need to be applied to the designated cavities precisely and without bubbles, and in the correct quantities. Gap fillers achieve high thermal conductivity through the addition of numerous fillers such as aluminium oxides. These can be highly abrasive though, leading to increased wear on components such as seals. On top of that, application through relatively narrow opening gaps results in small strokes with high flow speed, further intensifying the abrasion. That can make high-speed application in an automated process difficult, as it increases the level of abrasion and reduces the reliability of the applicator. Wiring harnesses The wiring harness is a key area of focus for automating the assembly of battery packs. They are usually assembled by hand in parts of the world where costs are low and can have thousands of individual wires for connecting sensors and processing units in a vehicle. A typical harness can weigh up to 60 kg and have a total length of several kilometres. However, there is growing interest in automating the process to bring the assembly closer to the production of the battery pack, reducing the risks to the supply chain. In one strand of research, a team at the Faculty of Mechanical Engineering boxes. There is nothing new about using two-component adhesives, they are common in other industries, but in the automotive sector they have only been used in small quantities in test vehicles and small-scale production. Developments in the application technology play an important role in efficient large-volume processing. The technology needs to adapt flexibly to different viscosities and mixing ratios, as well as support thermal balancing in the battery through the application of thermal interface materials. One-component adhesives are not sufficient for this. The battery packs in electric cars require protection, cooling and corrosion-resistant sealing. They also need the rigidity to withstand loads as a load-bearing component, and be crash-proof. Also required is a repair concept for detaching the glued covers without leaving any residue should a battery module need to be replaced. Another example of the need for two- component adhesives is underbody protection. Here, a one-component material is applied first, then two- component adhesives with a thermal conduction function are often used in the next step, for glueing cooling ribs on the battery module. Alternatively, joins can be glued using a one-component adhesive, with screws or welding points replaced by two-component adhesive dots. Two-component adhesives cure very quickly, allowing the sub-assemblies to be transported in a short time, while the one-component bond can cure during the next production step. A two-component structural adhesive is applied to the battery module separators, and two-component thermal conductive pastes are injected into the cavities to dissipate heat from the battery cells. An important role is also played by the corrosion protection, which is best achieved using the hot-melt method. To keep moisture out, the battery housing cover is tightly sealed using hot butyl at 160-180 ºC. The application technology for glueing battery packs includes the material supply using pumps, which transport the media through hoses into dosing systems. The components are then mixed in the correct ratio so that they can be applied as a homogeneous mixture. For high-precision adjustability, reproducibility and flexible variability of the application volumes, the control technology must be able to accurately record the stroke in the dosing piston and actuate it in the shortest possible time as changes are required. A newly developed system for two- component application is designed to be modular. The benefit here is the ease with which basic components can be replaced if process requirements change. For example, the pumps come in different sizes, with cartridge volumes up to 1000 litres to suit different automation strategies. The modular principle also includes a consistent control topology across all sub-assemblies, regardless of their size. This becomes more apparent when using materials with different viscosities. When mixed, it must be possible to adapt the pressure levels of the dosing pistons so that the materials can be mixed homogeneously. A focus on robotics does away with the need for rigid timing improving tOe ÅexiIility of manufacturing (Courtesy of B&R) Winter 2022 | E-Mobility Engineering 39 Focus | Automated manufacturing