As automotive brands bring more EVs to market, they need to address the safety issues related to electric engine batteries. Traditional internal combustion engines (ICE) have a wide operating temperature range (-40°C to 110°C) and typically shut down when overheated. However, electric engine batteries need to operate within a narrow temperature range to optimize energy efficiency and extend the engine’s service life – and risk thermal runaway that can create a fire hazard if they reach temperatures above 65°C.
Thermal management systems (TMS) are essential to ensuring ICE stay within the optimal engine operating temperature range as they run. In EVs, TMS are critical to keeping battery packs within the optimal temperature range to improve engine efficiency and service lifetimes as the EV operates. Additionally, TMS continue running when the EV is being charged to prevent battery pack thermal runaway – which is especially critical for fast EV charging. This requires manufacturers to ensure the thermoplastic components in TMS are tested to withstand more than 10,000 hours of exposure to coolant chemicals.
Lightweighting key coolant control components
In TMS, electric water pumps and coolant control valves are the key coolant control components. TMS for EVs and hybrid vehicles also require more precise coolant control than ICE vehicles, as more electric water pumps and control valves are used. These parts also need to be made lighter and meet more complex design requirements. Increasingly, manufacturers are using engineering thermoplastics that offer substantial material and production costs benefits to replace metals used in some TMS components.
Polyphenylene sulfide (PPS) is frequently used to manufacture TMS components, due to its excellent hydrolysis resistance and mechanical strength. However, alternative materials such as polyamides, which offer reliable hydrolysis resistance and mechanical properties, also meet different TMS application requirements. As a result, material suppliers need to provide high-performance and cost-effective hydrolysis-resistant polyamides and PPS for TMS components manufacturers.
DSM supplies a complete portfolio of materials optimized for TMS components and works directly with our customers to identify the materials best suited to the specific needs of their applications. XytronTM, our leading PPS compound, is ideal for developing TMS components that require the highest hydrolysis and heat aging resistance, including thermal management modules, coolant control valves and electric water pumps. Our ForTii® PPA and EcoPaXX PA410 materials also offer proven performance in system components such as coolant tubing, electric control valves and water jackets.
The industry’s leading PPS
Unique technology used in Xytron G4080HR results in a bonding interface between glass fibers and PPS resin that maximizes hydrolysis resistance while retaining the material’s mechanical properties after long term coolant aging. DSM conducted long-term water glycol (50%/50%) coolant aging testing at 135°C. Compared to a competing PPS, Xytron G4080HR demonstrates tensile strength that is 114% higher and elongation at break that is 63% higher after 3,000 hours of water glycol coolant aging – as well as weld line strength that is 85% higher after 1,000 hours of coolant aging. The material also demonstrates high purity and low leaching properties, which are very important for TMS components used in hydrogen fuel cell vehicles.
Shortening production cycles
Manufacturing compact, highly intricate automotive parts can quickly become cost and labor intensive. Components that fail validation testing due to production errors may result in lengthy part re-approval processes. DSM’s extensive experience with PPS and polyamide processing enables us to help our customers produce top-quality parts in fewer steps.
Our global teams provide on-site support for computer-aided engineering (CAE) molding processes – including Digimat-based anisotropic analyses that predict part performance with exceptional accuracy, resulting in next-level design quality. Each material in our TMS portfolio also offers high flow and easy processing capabilities that enable manufacturers to speed up cycle times and reduce operational costs.
DSM leverages our deep expertise in automotive, electric and electronic applications, and our best-in-class, cost-competitive materials to drive more value for our customers. Due to our strong partnerships with automotive industry leaders worldwide, manufacturers working with our materials often get parts approved by OEMs faster – leading to stronger business relationships. Our global services teams are prepared to support all your EV part manufacturing needs, and help you pursue a wide range of growth opportunities within the automotive market.