Magna’s one-piece battery enclosure prototype rolls off line

A battery enclosure prototype with a footprint of 2.8 m × 1.5 m has rolled off the line at Magna. R&D engineer Dong Xiaoxuan said the one-piece tray, called OptiForm™, is available for customers to conduct pack integration validation. It also achieves a 1.5° draft angle and 4 mm bottom radii, seeking to reclaim cell space traditionally “consumed” by stamped structures.

A battery enclosure must fit the cells, withstand crashes, keep out moisture and dust, and remain as light and inexpensive as possible. Aluminum extrusions, once a common option, are lightweight but somewhat more expensive. High-strength steel roll-formed parts cost less and offer strong impact resistance, but are heavier. Both approaches require numerous parts to be welded together. More welds mean more pronounced thermal distortion, while sealing becomes more dependent on the quality of each weld. As vehicles undergo long-term vibration and materials age, more connection points also mean a higher risk of leaks later in the vehicle’s life.

Magna’s approach is to stamp a single steel sheet into a tray and then add reinforcing structures inside. When conventional stamping draws flat steel into a deep, large enclosure, it often requires a larger draft angle—that is, sidewalls that slope outward—and larger radii to prevent cracking. OptiForm™ achieves a 160 mm draw depth and covers material thicknesses of 0.9–1.8 mm, reducing these space losses without changing the external dimensions. Magna says battery capacity could increase by up to 10%, but Xu Ziqing also made clear that how much ultimately translates into additional energy or range depends on the vehicle platform and battery-system design.

So, what exactly changes? When the vehicle’s dimensions remain unchanged, the additional space can accommodate more cells. Alternatively, if the range target remains unchanged, it can provide room for weight or cost reductions. Fewer welds, parts, processes and assembly operations could also reduce system costs. The approach uses mature stamping processes and can be completed with existing stamping equipment. Most of the transition workload lies not in modifying the production line, but in upfront process analysis, tooling adjustment and vehicle-level validation.

It is not a universal answer for every vehicle. In one architecture, the rocker panels and crossmembers in the vehicle floor carry side-impact loads, leaving the battery enclosure primarily responsible for protection, sealing and thermal management. In another, the battery pack still carries part of the crash load and must work with hot-formed reinforcement beams and other strengthening structures. Both approaches require automakers to define mounting points, load paths and battery safety boundaries jointly at an early platform stage. The OptiForm™ prototype now exists, but tooling and development costs are substantial. The solution is better suited to projects with sufficient production volume, long platform lifecycles or multiple vehicle models that can share the same package envelope and manufacturing route.