Copyright FOURIN, Inc. 2022
VW’s MEB Platform: Structural Analysis
VW’s BEV-only platform MEB (Modularer E-Antriebs-Baukasten) is a platform designed with the highest priority on protecting high-voltage drive batteries while reducing costs. Hot stamping material is used around the battery, and the amount of underbody high-tensile material was increased compared to the conventional MQB platform. In addition, aluminum is used for reducing weight of the battery case. On the other hand, about 30% of the upper body is made of mild steel similarly to conventional vehicles.
The underbody is exclusively made of steel, while the upper body uses a lot of steel as well (over 80% of the total). On the other hand, a hot-formed steel is combined with an aluminum extruded material or die-cast material around the battery to ensure strength especially against side collisions.
Battery scalability is also a feature of the MEB platform. Modularization is aimed to reduce manufacturing and procurement costs. The MEB platform is available in three battery capacity grades 45, 58 and 77kWh depending on the number of cell modules (ID.3). The case is shared by small and medium-capacity grades. The battery module is the same for all MEB-based models of the VW group around the world.
It may be said that the MEB platform was designed with a focus on the high-voltage battery exterior (battery case) that occupies most of the underbody. Due to the large capacity battery, a new load path for collisions was required. The ratio of high-tensile steel (about 420-1,000 MPa) in the entire underbody was increased 3.5 times compared to the MQB platform. Furthermore, the underbody around the battery and the seat crossbeams are made of hot-stamped material (MBW 1900 from Germany’s thyssenkrupp) which account for 28% of the entire underbody. VW has strengthened the underbody to protect the high-voltage battery from collisions in an effort to ensure safety. Meanwhile, a single concept is shared by all MEB variations regarding the seat crossbeam’s structure. VW aims to reduce cost by sharing the components.
The material composition of ID.3’s upper body is nearly identical with that of the MQB. The only difference is that an aluminum extrusion is used for the inner sill. It protects the high-voltage battery from side collisions. This shock absorbing method uses an aluminum crush box with different softness inside the inner sill.
Battery case safety requirements met in-house standards which are more stringent than global regulations. Aluminum is used as the case’s material. The case weighs 103kg without the module.