Hard-Soft Composite Concept Developed for Conductive Battery Components

Demand for plastics that can be integrated into existing material combinations to enhance thermal management in electric vehicle (EV) batteries and chargers has increased by leaps and bounds in recent years. To address this market need, Kraiburg TPE has launched a portfolio of thermally conductive thermoplastic elastomers (TPEs) that meet increased quality requirements and that it can ship in sufficient volumes to service the market.

The highest possible battery power density is consistently on the minds of designers, meaning installation space is typically limited. Further, batteries need to be charged in the shortest possible time. In this context, an intelligently designed thermal management system, which ensures that high temperatures generated in the battery during the charging process are dissipated quickly and continuously to the outside, is an essential prerequisite for the optimization of durability, since battery performance is degraded when it is exposed to high heat.

Service life extension

Kraiburg TPE recently has increased investment in the development of thermally conductive materials to guarantee batteries the longest possible service life. Compared to liquid or paste-like thermal conductors, these new TPEs provide the advantage of significantly higher functional and spatial stability when assembling the module.

“Apart from securing optimal heat transfer, our customers also benefit from the application advantages of thermoplastic injection molding,” said Annika Alke, a member of the development team at Kraiburg TPE. “Especially when large quantities are required, two-component hard/soft composites made of TPE and polyamide (PA) can play to their strengths with their high thermal conductivity.”

Another advantage of the newly developed thermally conductive TPEs is their special touch quality. Of particular note is the high-quality, evenly “dry” surface and the absence of PVC or silicones. The heat difference between ambient and body temperature is usually sufficient to produce a cooling effect on the skin when the user comes into contact with the material.

Adhesion testing of material combinations

Kraiburg TPE has collaborated with compounding partner Lehvoss Group to determine the overall performance of the new TPEs in different applications. As part of the jointly conducted tests, the newly developed TPEs were combined with thermally conductive and adhesion-optimized PA compounds from Lehvoss. The aim was to determine the adhesive properties of different material combinations, while working out the optimal processing parameters to finally launch a highly efficient solution. The results Lehvoss and Kraiburg TPE were able to achieve confirm the suitability of the new materials, particularly for applications in multicomponent composites.