Fraunhofer IWU, an institute for machine tools and forming technology, and Amsted Automotive, an automotive supplier, introduced an integrally designed battery housing with aluminum foam sandwiches. This special material structure consists of two solid aluminum sheets enclosing an inner core of aluminum foam.
This new development is in response to continued demand for electric vehicles in the automotive industry. According to Fraunhofer, “Battery housings in electric vehicles must be impact-resistant, absorb crash energy, protect against short circuits, and be heat-resistant. Efficient heat dissipation is essential, but cells also need protection from excessive cooling. The housing must resist damage from stones and salt, fit the vehicle’s underbody, add rigidity, and, being lightweight, help increase range. Aluminum foam satisfies these requirements.”
A unique aspect of the new battery housings is that, if needed, they can incorporate a cooling structure or a thermal storage medium known as Phase Change Material (PCM). Integrated PCM into closed-cell aluminum foam, PCM can absorb and store or release large amounts of thermal energy while changing its state (solid to liquid or vice versa) without significantly altering its own temperature. This makes them particularly well-suited for efficient thermal management in lithium-ion batteries.
Fraunhofer and Amsted presented a demonstrator of the battery housing design at the Battery Show North America in Detroit, MI, in early October. The demonstrator shows a wide range of possible serial solutions. Depending on the prioritized properties, pure AAS (Aluminum-Aluminum Foam Sandwiches), AAS with infiltrated PCM, AAS with a cooling structure, or AAS with a cooling structure and PCM can be implemented.
To ensure that battery housings made from aluminum foam can be used in mass-produced vehicles, researchers led by Dr. Thomas Hipke and Dr. Rico Schmerler are now focusing more on cost-effectiveness. A key factor in determining future manufacturing prices is the cost of raw materials. “We are increasingly using recycled material to produce the aluminum foam. Not only is this significantly more cost-effective, but it also greatly reduces the CO2 footprint,” said Hipke.
