Hella KGaA Hueck & Co in collaboration with the specialty chemicals company Lanxess has developed a new compound, called Pocan AF4130, for battery components in electric vehicles (EV). It serves as a housing material for a battery management unit (BMU) and two cell monitoring units (CMU). The blend of polybutylene terephthalate (PBT) and acrylic ester-styrene-acrylonitrile (ASA) contains 30 per cent by weight glass fibers and a halogen-based flame retardance package. “The particular advantages of the material are its extremely low warpage and shrinkage, combined with its high flame retardance. We see great potential for application in precision components for vehicle battery systems,” said Marc Marbach, Head of Sales Segments E&E in the Lanxess High Performance Materials (HPM) business unit. It took just two-and-a-half years to go from the initial idea to extensive testing and finally to use in full-scale production.
Hella fabricates the BMU and CMUs for a German manufacturer of battery systems for motor vehicles. The very flat devices currently are used in the lithium-ion battery system of a German compact car.
The housings of the BMU and CMUs have large, flat surfaces as well as complex geometries along the edges and on the inside. Thanks to their innovative design, they can be injection molded cost-effectively as single components. The contact pins for the connectors must not bend when the housings are mounted on the printed circuit boards. The tolerances for the spacing between the connector mounts and the cut-outs for the pins are therefore extremely close. “This is precisely where the outstanding dimensional stability of our blend Pocan AF4130 pays off,” explained Marbach.