FEA of a 48V-100Ah Battery Module Frame for Structural Strength

A client asked us to confirm that the frame of their 48V-100Ah battery module was strong enough before they committed to production. The frame carries the full weight of the module and holds it in place, so any weak spot puts the cells, the wiring and the surrounding equipment at risk.

Instead of building a prototype and hoping it holds, we found the problems on screen first. We ran a static structural finite element analysis (FEA) in Ansys and looked at three things that tell us whether a structure is safe: how far it deflects, how high the stresses climb and the safety factor across the part. The analysis gave a clear answer on strength and, just as usefully, showed the one area that needed reinforcement before manufacture.

The main question was simple: can this frame carry the module safely, and if not, where does it need help?

The frame performed well across most of its structure, but the analysis found one area that needs attention:

The safety factor plot told the most important part of the story. Across the bulk of the frame it was high, comfortably above the target, but in one small spot at the mounting base it dropped to about 0.41. Below 1, the material at that point would be pushed past its yield strength under the applied load, so this is a genuine weak point.

The biaxiality result in the same area showed a demanding, multi-directional stress state, which a fatigue or vibration check should look at more closely.

Because the analysis pinpointed the exact spot, the fix is straightforward and local. Any of these lifts the safety factor back above the target without adding much weight or cost to the rest of the frame:

The client could make a small, targeted change instead of over-building the whole enclosure, then move to production knowing the frame will hold the module safely.

Battery module frames and enclosures sit at the heart of every energy storage and electric vehicle system, and they have to stay strong through weight, vibration, shock and years of service. FEA catches a weak mounting point while it is still on screen, long before it turns into a warranty claim or a safety problem in the field. We cover the wider picture in our guide to EV battery pack thermal and structural simulation.