Proven mounting solutions for high-voltage batteries
The high-voltage battery is considered the heart of electric vehicles and must be integrated in the overall concept of the car body in the best possible way. By using WITOL tolerance compensation systems, the comparatively large components are connected to the car body precisely and without deformation. This leads to a simplified assembly process and a significant reduction in assembly times.
WITOLs are used both for the external connection of the battery housing to the body and for fastening the battery modules inside the battery housing:
- Tolerance compensation systems are crucial when connecting the high-voltage battery to the body to prevent deformation and achieve an optimum joint pattern.
- A universal screw connection for the internal connection also allows the removal and installation of individual cell modules.
- Saving heat conduction medium can save costs, extend battery life and improve performance.
Body connection of the high-voltage storage unit
High-voltage batteries, which are used in the electrified automotive industry, are rigid components with very high tolerances that have to be connected to the body. The high-voltage battery is a very sensitive component. Even a minimal distance between the contact surfaces can lead to unequal bending forces and tensions during assembly.
The bodywork, on the other hand, is comparatively susceptible to torsion, so considerable deformation of the bodywork and impairment of the gap dimensions and joint patterns can already occur during installation. Tension-free attachment of the battery to the vehicle underbody is therefore crucial for flawless quality.
WITOL has developed particularly robust tolerance compensation systems for the battery connection. The WITOLs are preassembled either on the battery housing or on the vehicle body. In the bolting process, the tolerances are compensated in the axial direction. By means of suitable slotted or square holes and sufficiently large screw heads, even compensation radially to the screw axis is possible.
Internal connection of the individual battery modules
The internal connection of the individual cell modules to the battery housing is also subject to tolerances. If the component is screwed together conventionally, the tolerances between the cell modules and the cooling base are usually compensated for with cost-intensive heat-conducting medium. This leads to poorer heat dissipation and higher vehicle weight. In addition, high compressive tensions can occur, which lead to deformation and insufficient thermal management of the high-voltage battery.
With the same active principle that is already used for the external connection of the high-voltage battery, WITOL tolerance compensation systems equalize the gap between the cell module and the housing flange without stress. The negative effects that arise in the conventional bolting process are thus effectively eliminated. The use of a universal screw connection also makes it possible to remove and install individual cell modules during servicing.
Optimal performance & cost savings through reduced use of gap filler
The cell module is pressed into the final position where the coolant is displaced and fixed in the final position with the WITOL tolerance compensation system. To ensure optimum thermal conductivity, the coolant must make full-surface contact between each cell module and cooling tray at all times. Unevenness no longer has to be filled by adding coolant, but can be better controlled by using WITOLs. As a result of the tolerance compensation, a smaller amount of coolant is required, which additionally leads to a significantly improved heat transfer. This enhances performance and extends the service life of the battery. The reduced use of materials also means that high costs and weight can be saved.
Mounting solutions for tailboard modules
Tailgate modules for electric vehicles can be opened manually or electrically and are significantly more complex components than ordinary filler necks. The tailgate module is a component that is bolted from the inside of the vehicle. Thus, the challenge is to align the painted cover flap flush with the outer skin of the body, resulting in a flush appearance.
Tolerances occur between the concealed vehicle structure and the outer panel and thus have a massive influence on the flushness of the cover flap. In addition, the tailgate modules themselves are also subject to tolerances. WITOL has developed compensating elements that are used to align the tailgate module, compensate for all tolerances and thus ensure a flush surface.