Wooden Batteries. A team of technicians led by Florian Feist and based at the Institute for Vehicle Safety at the Technical University of Graz, Austria, has created a protective casing for electric car batteries using a mix of wood and thin sheet steel instead of the aluminium extrusions currently used, a particularly energy-intensive production system
Hence the idea of replacing the aluminum with an extremely thin steel skin whose chambers are filled with wood. The steel skin is welded directly to the wooden core, whose cells collapse in the event of a crash, absorbing significant energy.
The underbody and cover are also made of a steel-wood composite, and the battery interior is reinforced with transverse ribs. Designed in this way, the structure has a significantly lower environmental impact than traditional structures, while being virtually equivalent in terms of functionality.
It should be noted that the battery housing is crucial to the safe operation of electric vehicles, as in the event of a crash, it protects the battery cells from excessive deformation, reducing the risk of fires. For this reason, prototypes of the new structure were subjected to several crash tests, one of which simulated a high-speed impact between a car and a round steel pillar. In this test, the hybrid housing’s intrusion values proved to be almost identical to those of the aluminum battery housings installed in the Tesla “Model S,” and fire and heat resistance tests also performed well.
“Bio!Lib,” as the structure was named, features a wooden section made of cork, a material that chars when exposed to high temperatures, causing a sharp drop in thermal conductivity—already low—and thus protecting the structures behind it.
In a pyrotechnic test simulating a battery fire, the battery cover withstood temperatures of over 1,300 degrees Celsius and bombardment with aluminum and copper particles. This performance surpassed that of Tesla’s battery cases when subjected to the same test. To assess the sustainability of the “Bio!Lib” project, researchers collaborated with the Wegener Center for Climate and Global Change at the University of Graz and determined the environmental impact of all materials and components used.
From the use of primary energy, water, and soil to the contamination of soils and bodies of water with toxic substances. In almost all other tests to which the casing was subjected, it offered better performance than the aluminum casings currently on the market, which prompted the Team to continue studies to verify the possibility of replacing the cork with low-quality wood deriving from thinning or secondary uses.
Title: “Wooden” Batteries: A New Protective Casing for Electric Car Batteries
Translation with Google
