Against the backdrop of increasingly strict emission limits, automotive engineering companies and their component suppliers are working at a feverish pace to develop new drive technologies. Of these, electric and hybrid vehicles in particular, place increasingly high demands on the cable harness and leads. Owing to voltages up to 1,000 V and the associated high currents, they have to withstand much higher temperatures than their predecessors.
With this in mind, we reached out to Hr. Dr. Henze, Senior Material Development Chemist with BASF to learn more about the thermoplastic polyurethane (TPU) solution that is standing up to high-heat challenges in modern vehicle applications.
Q: Why are high-performing TPUs needed in automotive cable harness and lead applications? What is the challenge?
A: TPUs show excellent mechanical and chemical resistance and therefore high reliability over the life-time of a car (or robot). Especially for applications like wheel speed sensor cables, rear view cameras, battery cables, and all cables that are installed “near-the-axle” are preferably jacketed with TPU. Another advantage is the easy processing by thermoplastic processing machines without further curing or crosslinking. “Standard” TPUs are used for Class C applications according to ISO 6722 for jacketing, due to decreased space in the wheel house (for example) for ASB/ESP-systems the requirements for long-term heat resistance are becoming increasingly strict.
Q: Why is this increasingly important in electric and hybrid vehicles?
A: In electric cars the current voltage is higher, therefore the cables get warmer during usage. Therefore, the next temperature class D is of interest, as described in our paper that we are presenting at IWCS .
Q: Are there regulations surrounding what products/materials can be used in these applications?
A: Yes. Many. For example: ISO 6722 (class C to D) or LV 112 for automotive applications and UL 1581 for industrial applications.
Q: What other applications are there for Elastollan® in the automotive industry?
A: In Wire and Cables: external charger cables for electric cars (EVC, electric vehicle charging). Or power and sensor cables in robots that are used for the assembly and welding of cars.
Outside of Wire & Cable: tubes for conveying liquids or air for lumbar support, films for foam skinning, interior parts, outside parts such as Citroen Cactus, and Door handles.
Q: How is Elastollan® different from competitive products?
A: It depends. What is competitive? Other TPUs? Or other polymers? In general, the balance of mechanical, thermal and chemical reliability in combination with thermoplastic processability and global availability. Tailor made formulations possible with variations of hardness, glossy or matt surface, different loadings of flame-retardant additives for specific flame-retardant tests, plasticized or not…. To other competing TPUs; our wide product spectrum, excellent technical service, lot consistency and high-speed processability (total cost of ownership).
Q: What other Wire & Cable industries and applications are Elastollan® used in?
A: Elastollan offers a variety of outstanding properties. Among them are its durability, flexibility through a wide temperature range and excellent moisture resistance. With this in mind, there are applications in a wide range of industries, including: agriculture, construction, electric & electronics, furniture, health and safety, industrial, military, mining and geophysical, sports and recreation, textile, and of course, transportation.
Q: Are there other new applications coming in the future?
A: Yes. In Wire & Cable we see increasing interest in consumer device cabling. That means new applications outside of automotive and robotics.