Electric Car Components: Enhancing Safety, Performance, and Efficiency

Mobility undergoes a profound change as public and government initiatives seek to replace the combustion engine with sustainable alternatives. Electric vehicles (EVs) require high-performance batteries, crash-safe structures, effective battery cooling, and stable powertrain components. Our materials and coatings empower manufacturers to create enhanced EVs.

Fitting numerous fast-charging cells into an electric car battery necessitates flame-retardant, impact-resistant, and temperature-stable components. Our lightweight Bayblend® FR polycarbonate and ABS blend serve as an ideal solution for cell holders and EV battery modules, maintaining stability at 80°C for optimal efficiency while meeting the UL94 V-0 flame retardancy rating. Additionally, our Makroblend® resin provides the durability required for protective housing, withstanding vibration, impact, and abuse testing conditions.

• Low viscosity system to fill thinnest gaps
• High degree of processing automation

• Lightweight foam formulation 
• Optimized adhesion to interface materials to ensure the mechanical integrity of the pack
• Tailored mechanical foam properties to protect the cells against loads and vibration
• Temperature- and aging-optimized formulation
• Thermal insulation and protection of cells in case of a thermal runaway.

Baydur® Polyurethane is an ideal material to manufacture composite battery top cover using the High-Pressure Resin Transfer Molding (HP-RTM) process. 

• Improved product efficiency
• Down to 0.8 mm part thickness of geometry

• Lightweight solution (weight saving 60 % vs. steel, 50 % vs. SMC, 20 % vs. aluminum alloy)
• Combined with flame-retardant additives meets 1.0 mm UL94 V-0
• High mechanical strength and stiffness across a wide range of temperatures

Battery cells require safety measures to prevent risks in terms of thermal runaway caused by a potential mechanical impact from the side or the bottom, e.g., in case of a crash. Covestro has developed Baysafe® EA, a versatile Polyurethane rigid foam, which is tailored to energy absorption.

• Foaming enables complex and large geometries to optimize crash pads to the available space
• Good adhesion to adjacent surfaces

• Lightweight foam solution 
• Thermal insulation of battery
• Tailored mechanical foam properties
• Lower temperature dependency of mechanical properties compared to most thermoplastics
• Conversion of crash energy into foam cell deformation and heat

As electric car battery technology evolves, lightweight modular, extendable frames, reinforcement beams, and battery housings enable manufacturers to easily meet future performance demands. Pultrusion stands out as a proven, cost-efficient manufacturing process for creating these composite parts from polyurethane resin and glass or carbon fibers. Notably, a battery pack made from our Baydur® PUL material outperformed a benchmark battery pack in virtual crash testing, measuring energy absorption, deformation, shock, and vibration

Electric cars are steering a transition from semi-crystalline to amorphous materials in powertrain components. These components, ranging from high voltage plugs to sensors, converters, inverters, and bus bars, require enhanced dimensional stability, minimal warpage, reduced humidity absorption, and resistance to electronic corrosion. Our Apec® FR, Bayblend® FR, Makroblend® FR, and Makrolon® TC offer an extensive array of materials meeting these specifications, featuring isotropic shrinkage and phosphorous-based flame-retardancy without susceptibility to electro corrosion

High-speed charging poses a risk of overheating electric car batteries, optimal at temperatures under 40°C for peak efficiency and longevity. Our battery packaging aligns with effective thermal management strategies. Bayblend® FR4065 EV maintains strength when in contact with water/glycol battery coolants. Flame-retardant Bayblend® FR3042, FR3080 EV, and FR 3040 are suited for air-cooled systems. Specific grades of Makrolon®, Bayblend®, and Makroblend® exhibit chemical resistance to phase change materials. Makrolon® TC grades provide enhanced thermal conductivity while maintaining flow and ductility.

Covestro presently provides high-performance polyurethane raw materials to meet the current standards for thermally conductive structural adhesives, gap fillers, and sealants used in the assembly of EV battery packs.

• Desmodur® E: Our broad portfolio of aliphatic and aromatic prepolymer solutions boasts a high degree of formulating latitude. 
• Desmodur® ultra: Our ultra-low monomer content polyurethane hardeners can be used to improve the industrial hygiene profile of formulated products used in EV battery applications.
• Desmoseal® S: Our Silane Terminated polyurethane technology offers improved adhesion performance on a wide range of substrates coupled with an alternative silane curing technology