The battery tray is the battery socket on a car. It must be mechanically stable and secured to the entire body of the vehicle. However, it is no longer a single component simply connected to the electric car. Additionally, the battery tray has been fully integrated into the body of the car. Complex aluminum welding designs include all battery cells, connectors, and control units. In addition, the battery pack includes various numbers of battery modules.
The thermal expansion of the battery pack during charging and driving can cause twisting and bending of the tray. Various dimensional characteristics, such as the length, diameter, and position of the slots, must be measured using random sampling or complete automatic detection at the end of the production line. A large number of characteristics require a fast inspection cycle involving multi-sensor measurements. Non-contact optical laser scanners can quickly extract feature data, while tactile probe systems can achieve bottom-cut and other challenging optical features.
Due to the large amount of energy in the battery cells, the alloy battery tray must be properly integrated into the body of the vehicle and ensure the safety of the battery in the event of a collision. Connection points (i.e., welding bolts) connect it to the rest of the vehicle body. The size and position of these welding points are crucial for the fully automatic battery tray assembly process and the load-bearing structure connection when driving, charging, and in the event of an accident. All of these requirements result in extensive and varied characteristics that can be covered by a flexible user-defined probe system or by using optical sensors to scan point clouds.
The results of the measurement are a digital copy or twin that displays the true geometry of the battery tray. Process-related inspection features, such as the position of fixing holes, can be extracted from the 3D point cloud and evaluated in trend analysis. Early detection of changes in the production process can be achieved through trend analysis based on full-field measurements. During problem analysis, the color-coded surface deviations of the 3D point cloud help to achieve the desired nominal CAD geometry. Using the GD&T function, flatness or surface contour of seal surfaces or individual battery compartments can be calculated. Similarly, the height and position of sealing beads can be easily captured.
In digital assembly, the interaction between the battery modules and the battery traycan be evaluated. Assembly situations can be simulated and optimized by different local alignments. The problem of gap size changes caused by thermal deformation of the battery module after cyclic testing can also be easily answered. Surface deviations between battery modules and battery tray can also be used to calculate the volume of thermal grease required for each battery compartment.